Investigator

Daisuke Aoki

Keio University

DADaisuke Aoki
Papers(12)
Hormone replacement t…High-Throughput Drug …Prognostication of ea…Evaluation of safety …Hysteroscopic Photody…A retrospective study…A prospective cohort …Prognostic Biomarker …Current treatment str…Low CD86 expression i…An attempt to establi…Retrospective evaluat…
Collaborators(10)
Wataru YamagamiYusuke KobayashiAikou OkamotoSatoru NagaseTakayuki EnomotoHidetaka KatabuchiMikio MikamiKazuhiro TakeharaTatsuyuki ChiyodaHidemichi Watari
Institutions(9)
Keio UniversityUniversity of TsukubaJikei University Scho…Yamagata University F…Niigata University Gr…Kumamoto UniversityShonan University of …Shikoku Cancer CenterHokkaido University

Papers

High-Throughput Drug Screening of Clear Cell Ovarian Cancer Organoids Reveals Vulnerability to Proteasome Inhibitors and Dinaciclib and Identifies AGR2 as a Therapeutic Target

Abstract There are currently no effective treatments available for clear cell ovarian cancer (CCC). In this study, we aimed to identify effective drugs for CCC through high-throughput drug screening (HTDS) using ovarian cancer organoids and determine novel therapeutic targets based on the biological characteristics of CCC through omics analysis. An ovarian cancer organoid biobank was established, and HTDS was conducted using CCC organoids based on libraries of 361 and 4,560 compounds. The efficacy of the identified drugs was verified in in vitro and in vivo experiments using a patient-derived organoid xenograft mouse model. Transcriptome analysis was performed to identify genes related to the pathways targeted by the identified drugs in CCC and to assess their potential as therapeutic targets. Proteasome inhibitors and dinaciclib were extracted using HTDS and shown to inhibit tumorigenesis in vitro and in vivo. CCC, like multiple myeloma, exhibited activated endoplasmic reticulum (ER) stress and unfolded protein response (UPR), and treatment with proteasome inhibitors further enhanced ER stress and UPR, ultimately leading to cell death. Transcriptome analysis identified anterior gradient-2 (AGR2) as a key gene involved in UPR in CCC. CRISPR knockout of AGR2 suppressed cell proliferation, increased sensitivity to proteasome inhibitors, and reversed platinum resistance in CCC. AGR2 knockout also upregulated Schlafen 11, contributing to platinum sensitivity. ER stress and the UPR are activated in CCC, and proteasome inhibitors disrupt this balance, ultimately leading to cell death. AGR2 may serve as a potential therapeutic target in CCC. Significance: Proteasome inhibitors and dinaciclib are identified as effective drugs for CCC. CCC has a high basal UPR, and proteasome inhibition may disrupt this balance. AGR2 is involved in the UPR of CCC, and inhibiting AGR2 further enhances the UPR and confers platinum sensitivity, making it a potential therapeutic target.

Evaluation of safety and diagnostic performance for flexible hysteroscopy in 1591 outpatient cases

AbstractBackgroundTo date, only few large studies are available concerning the safety and diagnostic concordance rates of outpatient flexible hysteroscopy. In our institution, outpatient hysteroscopy has been routinely and educationally applied Kosuke Tsuji to intrauterine lesions; thus, we retrospectively investigated the institution’s outpatient flexible hysteroscopy cases.MethodsA total of 1591 cases of outpatient flexible hysteroscopy conducted at our institution in 2012–2016 were retrospectively analyzed in terms of their clinical background, complications and diagnostic concordance rates.ResultsA total of 1591 cases included 546 cases of benign tumors (317 endometrial polyps, 168 myomas and 61 endometrial hyperplasia), 361 cases of atypical endometrial hyperplasia, 571 cases of endometrial cancers and 113 cases of other diagnoses. No major complications, including uterine perforation, occurred. However, one patient (0.06%) was diagnosed with septic shock caused by intrauterine infection that required prolonged immunosuppressive drug administration. Meanwhile, 335 patients diagnosed with benign tumors through outpatient flexible hysteroscopy underwent operation, and the diagnostic concordance rate was 74.6% (250 cases). However, this rate included 14 cases (4.2%) diagnosed with malignant tumors postoperatively. In preoperative endometrial cancer cases, the sensitivity and specificity for cervical invasion diagnosis were 39.4 and 90.8%, respectively. In addition, only one patient manifested positive ascites cytology intraoperatively, possibly caused by outpatient hysteroscopy.ConclusionsOutpatient flexible hysteroscopy is highly safe, with a slight negligible effect on ascites cytology. However, the diagnosis should be determined by multidisciplinary approaches, as hysteroscopy alone can miss malignancy.

Hysteroscopic Photodynamic Diagnosis Using 5-Aminolevulinic Acid: A High-Sensitivity Diagnostic Method for Uterine Endometrial Malignant Diseases

To examine the diagnostic accuracy of hysteroscopic photodynamic diagnosis (PDD) using 5-aminolevulinic acid (5ALA) in patients with endometrial cancer and premalignant atypical endometrial hyperplasia. A single-center, open-label, exploratory intervention study. University Hospital in Japan. Thirty-four patients who underwent hysteroscopic resection in the Department of Obstetrics and Gynecology at Keio University Hospital. Patients were given 5ALA orally approximately 3 hours before surgery and underwent observation of the uterine cavity and endometrial biopsy using 5ALA-PDD during hysteroscopic resection. Specimens were diagnosed histopathologically and the diagnostic sensitivity and specificity of hysteroscopic 5ALA-PDD for malignancy in the uterine cavity was determined. Red (R), blue (B), and green (G) intensity values were determined from PDD images, and the relationships of histopathological diagnosis with these values were used to develop a model for objective diagnosis of uterine malignancy. Three patients were excluded from the study because of failure of the endoscope system. A total of 113 specimens were collected endoscopically. The sensitivity and specificity of 5ALA-PDD for diagnosis of malignancy in the uterine cavity were 93.8% and 51.9%, respectively. The R/B ratio in imaging analysis was highest in malignant lesions, followed by benign lesions and normal uterine tissue, with significant differences among these groups (p <.05). The R/B and G/B ratios were used in a formula for prediction of malignancy based on logistic regression and the area under the receiver operating characteristic curve for this formula was 0.838. At a formula cutoff value of 0.220, the sensitivity and specificity for diagnosis of malignant disease were 90.6% and 65.4%, respectively. To our knowledge, this is the first study of the diagnostic accuracy of 5ALA-PDD for malignancies in the uterine cavity. Hysteroscopic 5ALA-PDD had higher sensitivity and identifiability of lesions. These findings suggest that hysteroscopic 5ALA-PDD may be useful for diagnosis of minute lesions.

A retrospective study for investigating the relationship between old and new staging systems with prognosis in ovarian cancer using gynecologic cancer registry of Japan Society of Obstetrics and Gynecology (JSOG): disparity between serous carcinoma and clear cell carcinoma

International Federation of Gynecology and Obstetrics (FIGO) staging for ovarian, fallopian tube, and peritoneal cancers was revised in 2014. The aim of this study is to clarify whether the revised FIGO2014 staging reflects the prognosis of patients with ovarian cancer by histological type in Japan. We extracted 9,747 patients who were diagnosed with ovarian cancer since 2004 until 2008 and who could be classified into appropriate stages from the Gynecologic Cancer Registry of Japan Society of Obstetrics and Gynecology. These cases were analyzed after revision to FIGO2014 based on the pTNM classification. Among stage I, the 5-year overall survival rate (5y-OS) in FIGO2014 was 94.9% in stage IA, 92.3% in stage IC1, 86.1% in IC2, and 84.9% in IC3 with significant differences between stages IA and IC1 (p=0.012), IC1 and IC2 (p<0.001). There was a significant difference between stages IA and IC1 in clear cell and mucinous carcinoma but not in serous and endometrioid carcinoma. Among stage III, the 5y-OS was 75.6% in stage IIIA1, 68.9% in IIIA2, 58.6% in IIIB, and 44.4% in IIIC, with significant differences between stages IIIA2 and IIIB (p=0.009), IIIB and IIIC (p<0.001). Among stage IV, the 5y-OS was 43.1% in stage IVA* and 32.1% in IVB with a significant difference (p=0.002). The results suggest that changes in classification for stage III and stage IV are appropriate, but the subclassification for stage IC might be too detailed. There was a discrepancy of prognosis by histological type between stage IA and IC1.

A prospective cohort study on the safety and efficacy of bevacizumab combined with chemotherapy in Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer

Abstract Objective this prospective cohort study aimed to assess the safety and efficacy of bevacizumab combined with chemotherapy in Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer. Methods in this study, 40 Japanese patients with relapsed ovarian, fallopian tube or primary peritoneal cancer selected to receive bevacizumab with chemotherapy were enrolled. Patients in poor general condition were excluded. Each patient was monitored prospectively for adverse events, administration status, disease status and survival. Treatment was continued until intolerable adverse events or disease progression. The primary endpoint was safety. Results bevacizumab plus platinum-based chemotherapy was performed for 30 patients (median cycle; 16.5), while bevacizumab plus non-platinum chemotherapy was performed for 10 patients (median cycle; 5.5). Among bevacizumab-related adverse events, hypertension occurred in 80% of patients, proteinuria in 83%, mucositis in 25%, bleeding in 20%, thromboembolic events in 5.0% and fistula in 2.5%. Gastrointestinal perforation or other life-threatening lethal adverse events were not observed. Response rate and median progression-free survival were 73% and 19.3 months for patients with bevacizumab plus platinum-based chemotherapy, and 30% and 3.9 months for patients with bevacizumab plus non-platinum chemotherapy, respectively. There was no correlation between response rate and occurrence of adverse events such as hypertension or proteinuria. Conclusion bevacizumab combined with chemotherapy was tolerable and effective for Japanese patients with relapsed ovarian cancer, fallopian tube cancer or primary peritoneal cancer. Hypertension and proteinuria are frequently occurred and managed properly for continuing treatment.

Prognostic Biomarker of Fertility‐Preserving Hormonal Therapy Based on Multigene Panel Testing for Endometrial Cancer

ABSTRACT In this study, we identified prognostic biomarkers that predict treatment outcome in patients receiving fertility‐preserving high‐dose medroxyprogesterone acetate (MPA) therapy through comprehensive multigene panel testing. A total of 38 patients (20 atypical endometrial hyperplasia and 18 stage IA G1 without myometrial invasion) who received first‐line MPA therapy were enrolled. Genomic DNA was extracted from formalin‐fixed paraffin‐embedded samples, and PleSSision‐Rapid multigene panel testing was performed. Of the 38 patients, 31 (82%) achieved complete response (CR), 2 (5%) had stable disease (SD), and 5 (13%) had progressive disease (PD) following initial treatment. The median duration to achieve tumor disappearance was 7 months (range: 4–14 months). Following initial treatment, 25 of 32 patients (78%) experienced recurrence, with a median recurrence‐free survival (RFS) of 21 months (range: 2–84 months). The most frequently observed actionable gene mutations were PTEN (68.4%), CTNNB1 (55.2%), and PIK3CA (33.3%). Patients harboring PTEN mutations in EMG1 required a significantly longer duration to achieve tumor disappearance ( p  = 0.011). In addition, the presence of PIK3CA mutations in AEH was significantly associated with shorter RFS ( p  = 0.048). Molecular classification identified 34 patients (89%) with no specific molecular profile (NSMP), 1 patient (3%) with POLE mutation, and 3 patients (8%) with deficient mismatch repair (d‐MMR). Most patients undergoing MPA therapy were classified as having NSMP. Genetic alterations, specifically mutations in PTEN and PIK3CA , were significantly associated with treatment outcomes, highlighting their potential as prognostic biomarkers.

Current treatment strategies for ovarian cancer in the East Asian Gynecologic Oncology Trial Group (EAGOT)

Ovarian cancer, notable for its severe prognosis among gynecologic cancers, has seen substantial progress in treatment approaches recently. Enhanced protocols in chemotherapy and the introduction of poly (ADP-ribose) polymerase (PARP) inhibitors for maintenance therapy have markedly improved outcomes for patients with specific genetic profiles, such as those positive for BRCA mutations or exhibiting homologous recombination deficiency (HRD). Additionally, the method of intraperitoneal chemotherapy administration has emerged as a valuable alternative to traditional transvenous routes, showing promise for wider clinical adoption. The field of surgery has also evolved, with increasing exploration into the benefits and feasibility of laparoscopic methods over more invasive traditional surgeries, aiming for complete tumor removal but with reduced patient impact. The hereditary nature of ovarian cancer underscores the importance of genetic testing, which has become integral in tailoring treatment strategies, particularly in determining suitability for PARP inhibitors. The formation of the East Asian Gynecologic Oncology Trial Group (EAGOT) aims to optimize treatment across Japan, Korea, China, and Taiwan. The ovarian cancer committee of EAGOT shared the current policies, focusing on 5 topics: 1) strategies for maintenance therapy after initial surgery and chemotherapy, 2) drug regimens for platinum-sensitive and platinum-resistant recurrence, 3) intraperitoneal chemotherapy, 4) laparoscopic surgery as an alternative to laparotomy, and 5) current status of genetic testing (BRCA, HRD, and panel tests) for ovarian cancer and its prospects. EAGOT's multi-national trials aim to harmonize these evolving treatment strategies, ensuring that the latest and most effective protocols are accessible across the region, thereby significantly impacting patient outcomes in East Asia.

Low CD86 expression is a predictive biomarker for clinical response to the therapeutic human papillomavirus vaccine IGMKK16E7: results of a post hoc analysis

Abstract Background Although therapeutic human papillomavirus vaccines could offer a noninvasive treatment for patients with cervical intraepithelial neoplasia, none has been clinically implemented. Oral administration of the therapeutic human papillomavirus vaccine IGMKK16E7 results in the histological regression of human papillomavirus 16–positive cervical intraepithelial neoplasia 2/3 to normal (complete response). We investigated biomarkers that could predict complete response after oral administration of IGMKK16E7. Methods Forty-two patients administered high-dose oral IGMKK16E7 in a phase I/II trial were included. Cervix-exfoliated cells were collected before vaccine administration. Gene expression of CD4, CD8, FOXP3, programmed cell death 1 protein, CTLA4, CD103, CD28, CD80, CD86, and programmed cell death 1 ligand 1 in the cells was measured by quantitative reverse transcriptase–polymerase chain reaction. Receiver operating characteristic curve analysis and Mann-Whitney tests were used to explore potential biomarkers. Pearson correlation coefficient analysis was used to correlate gene expression profiles with clinical outcome. Results The only predictive biomarker of vaccine response for which receiver operating characteristic curve analysis showed significant diagnostic performance with histological complete response was CD86 (area under the curve = 0.71, 95% confidence interval = 0.53 to 0.88, P = .020). Patients with complete response had significantly lower CD86 expression (CD86-low) than patients with no complete response (P = .035). The complete response rates for CD86-low and CD86-high patients were 50% and 19%, respectively, and CD86-low patients had a significantly higher complete response rate (P = .047). Compared with all patients, the CD86-low group had a 1.5-fold increase in the complete response rate. Gene expression of CD86 and CTLA4 showed the strongest positive correlation with clinical outcomes in the incomplete response group (P &amp;lt; .001). Conclusion Low expression of CD86 in exfoliated cervical cells can be used as a pretreatment biomarker to predict histological complete response after IGMKK16E7 administration.

An attempt to establish real-world databases of poly(ADP-ribose) polymerase inhibitors for advanced or recurrent epithelial ovarian cancer: the Japanese Gynecologic Oncology Group

The development of new treatments for gynecological malignancies has been conducted mainly through collaborative international phase III trials led by the United States and Europe. The survival outcomes of many gynecological malignancies have greatly improved as a result. Recent large-scale genome-wide association studies have revealed that drug efficacy and adverse event profiles are not always uniform. Thus, it is important to validate new treatment options in each country to safely and efficiently provide newly developed treatment options to patients with gynecological malignancies. The Japanese Gynecologic Oncology Group (JGOG) is conducting 5 cohort studies (JGOG 3026, 3027, 3028, 3030, and 3031) to establish real-world data (RWD) of poly(ADP-ribose) polymerase (PARP) inhibitor use in patients with advanced or recurrent epithelial ovarian cancer. The RWD constructed will be used to provide newly developed PARP inhibitors for women with advanced or recurrent ovarian cancer in a safer and more efficient manner as well as to develop further treatment options. In 2022, The JGOG, Korean Gynecologic Oncology Group, Chinese Gynecologic Cancer Society, and Taiwanese Gynecologic Oncology Group established the East Asian Gynecologic Oncology Trial Group to collaborate with East Asian countries in clinical research on gynecologic malignancies and disseminate new knowledge on gynecologic malignancies from Asia. The JGOG will conduct a collaborative integrated analysis of the RWD generated from Asian countries and disseminate real-world clinical knowledge regarding new treatment options that have been clinically implemented.

Retrospective evaluation of risk-reducing salpingo-oophorectomy for BRCA1/2 pathogenic variant carriers among a cohort study in a single institution

Abstract Background Risk-reducing salpingo-oophorectomy is performed for the primary prevention of ovarian cancer in patients with hereditary breast–ovarian cancer syndrome. We performed risk-reducing salpingo-oophorectomy for the first time in Japan in 2008, and we experienced 20 cases of risk-reducing salpingo-oophorectomy through 2019. In the past, the use of risk-reducing salpingo-oophorectomy in Japan was restricted because it was not covered by a Japanese National Health Insurance. Since April 2020, risk-reducing salpingo-oophorectomy has been covered by insurance for patients with breast–ovarian cancer syndrome and pre-existing breast cancer, and this surgery is expected to become more widely implemented in Japan. Methods To contribute to the widespread use of risk-reducing salpingo-oophorectomy in the future, we retrospectively reviewed 20 cases of risk-reducing salpingo-oophorectomy at our hospital cohort study to clarify the issues in its implementation. Results The variant genes for which risk-reducing salpingo-oophorectomy was indicated were BRCA1 and BRCA2 in 13 (65%) and 7 patients (35%), respectively. The median age at which risk-reducing salpingo-oophorectomy was performed was 49 years (range, 38–58), 13 patients (65%) had gone through menopause, and 16 patients (80%) had a history of breast cancer. Of the five patients (25%) with vasomotor symptoms, four received Chinese medicine, and only one received hormone replacement therapy. Occult cancer was detected in the removed ovaries in two patients (10%), although no postoperative peritoneal carcinogenesis has been observed to date. Conclusions Women who paid for risk-reducing salpingo-oophorectomy out of pocket were older than the recommended age at which the procedure should be performed, and this may explain the higher rate of occult cancers than previously reported. We need to perform risk-reducing salpingo-oophorectomy at the recommended age to ensure that the procedure is effective for primary prevention.

Lymphadenectomy for primary ovarian cancer: a systematic review and meta-analysis

To assess the effectiveness of lymphadenectomy at primary debulking surgery (PDS) on the survival of patients with epithelial ovarian cancer (EOC). We searched PubMed, Ichushi, and the Cochrane Library. Randomized controlled trials (RCTs) and retrospective cohort studies comparing survival of women with EOC undergoing lymphadenectomy at PDS with that of women without lymphadenectomy were included. We performed a meta-analysis of overall survival (OS), progression-free survival (PFS), and adverse events. For advanced-stage EOC, 2 RCTs including 1,074 women and 7 cohort studies comprising 3,161 women were evaluated. Meta-analysis revealed that lymphadenectomy was associated with improved OS (hazard ratio [HR]=0.80; 95% confidence interval [CI]=0.70-0.90). However, meta-analysis of 2 RCTs revealed no significant difference in OS between the lymphadenectomy and no-lymphadenectomy groups (OS: HR=1.02; 95% CI=0.85-1.22). For early-stage EOC, 1 RCT comprising 268 women and 4 cohort studies comprising 14,228 women were evaluated. Meta-analysis showed that lymphadenectomy was associated with improved OS (HR=0.75; 95% CI=0.68-0.82). A RCT of early-stage EOC reported that lymphadenectomy was not associated with improved OS (HR=0.85; 95% CI=0.49-1.47). Surgery-related deaths were similar in both groups (risk ratio [RR]=1.00; 95% CI=0.99-1.01); however, blood transfusion was required less frequently in the no-lymphadenectomy group (RR=0.74; 95% CI=0.63-0.86). Meta-analysis of RCTs and observational studies suggest that lymphadenectomy was associated with improved OS in advanced- and early-stage EOC. However, results from RCTs demonstrate that lymphadenectomy was not associated with improved OS in advanced- and early-stage EOC.

Nivolumab Versus Gemcitabine or Pegylated Liposomal Doxorubicin for Patients With Platinum-Resistant Ovarian Cancer: Open-Label, Randomized Trial in Japan (NINJA)

PURPOSE This phase III, multicenter, randomized, open-label study investigated the efficacy and safety of nivolumab versus chemotherapy (gemcitabine [GEM] or pegylated liposomal doxorubicin [PLD]) in patients with platinum-resistant ovarian cancer. MATERIALS AND METHODS Eligible patients had platinum-resistant epithelial ovarian cancer, received ≤ 1 regimen after diagnosis of resistance, and had an Eastern Cooperative Oncology Group performance score of ≤ 1. Patients were randomly assigned 1:1 to nivolumab (240 mg once every 2 weeks [as one cycle]) or chemotherapy (GEM 1000 mg/m2 for 30 minutes [once on days 1, 8, and 15] followed by a week's rest [as one cycle], or PLD 50 mg/m2 once every 4 weeks [as one cycle]). The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), overall response rate, duration of response, and safety. RESULTS Patients (n = 316) were randomly assigned to nivolumab (n = 157) or GEM or PLD (n = 159) between October 2015 and December 2017. Median OS was 10.1 (95% CI, 8.3 to 14.1) and 12.1 (95% CI, 9.3 to 15.3) months with nivolumab and GEM or PLD, respectively (hazard ratio, 1.0; 95% CI, 0.8 to 1.3; P = .808). Median PFS was 2.0 (95% CI, 1.9 to 2.2) and 3.8 (95% CI, 3.6 to 4.2) months with nivolumab and GEM or PLD, respectively (hazard ratio, 1.5; 95% CI, 1.2 to 1.9; P = .002). There was no statistical difference in overall response rate between groups (7.6% v 13.2%; odds ratio, 0.6; 95% CI, 0.2 to 1.3; P = .191). Median duration of response was numerically longer with nivolumab than GEM or PLD (18.7 v 7.4 months). Fewer treatment-related adverse events were observed with nivolumab versus GEM or PLD (61.5% v 98.1%), with no additional or new safety risks. CONCLUSION Although well-tolerated, nivolumab did not improve OS and showed worse PFS compared with GEM or PLD in patients with platinum-resistant ovarian cancer.

A phase I study of combined trabectedin and pegylated liposomal doxorubicin therapy for advanced relapsed ovarian cancer

Abstract Background Advanced relapsed ovarian cancer has a poor prognosis, and treatment options are limited. Methods This phase I trial investigated the dosage, safety, pharmacokinetics and efficacy of trabectedin plus pegylated liposomal doxorubicin (PLD) in Japanese patients with advanced relapsed ovarian, fallopian tube, or primary peritoneal cancer. Patients received trabectedin 0.9 or 1.1 mg/m2 immediately after PLD 30 mg/m2; both drugs were given by intravenous infusion. Treatment was repeated every 21 days until disease progression or unacceptable toxicity. The maximum tolerated dose (MTD) was determined in an initial dose escalation phase, and this was used in a subsequent safety assessment phase. Safety and tumor response were monitored throughout the trial, and drug concentrations for pharmacokinetic analysis were measured during cycle 1. Results Eighteen patients were included. The MTD of trabectedin was determined as 1.1 mg/m2. Gastrointestinal adverse events were experienced by all patients, but were mostly grade 1 or 2 in intensity. Most patients had grade ≥ 3 elevations in transaminase levels or grade ≥ 3 reductions in neutrophil count, but these events were generally manageable through dose reduction and/or supportive therapies, as appropriate. There were no deaths during the trial. Trabectedin exposure increased in a dose-dependent manner. The overall response rate was 27.8%. Conclusions Trabectedin, in combination with PLD, may have clinical benefits in Japanese patients with relapsed advanced ovarian cancer. The recommended dosage of trabectedin for further study in this population is 1.1 mg/m2 once every 21 days. Clinical trial registration number: JapicCTI-163164

Japanese nationwide observational multicenter study of tumor BRCA1/2 variant testing in advanced ovarian cancer

AbstractThe association between germline BRCA1 and BRCA2 pathogenic variants (mutations: gBRCAm) and ovarian cancer risk is well established. Germline testing alone cannot detect somatic BRCA1/2 pathogenic variants (sBRCAm), which is calculated based on the proportion of tumor BRCAm (tBRCAm) from tumor samples and gBRCAm. Homologous recombination deficiency (HRD) results mainly from genetic/epigenetic alterations in homologous recombination repair‐related genes and can be evaluated by genomic instability status. In Japan, the prevalence of tBRCAm, sBRCAm, and HRD remains unclear. This multicenter, cross‐sectional, observational study, CHaRacterIzing the croSs‐secTional approach to invEstigate the prevaLence of tissue BRCA1/2 mutations in newLy diagnosEd advanced ovarian cancer patients (CHRISTELLE), evaluated the prevalence of tBRCAm, sBRCAm, and HRD in tumor specimens from newly diagnosed patients with ovarian cancer who underwent gBRCA testing. Of the 205 patients analyzed, 26.8% had a tBRCAm, including tBRCA1m (17.6%) and tBRCA2m (9.3%). The overall prevalence of tBRCAm, gBRCAm, sBRCAm, and HRD‐positive status was 26.8%, 21.5%, 6.3%, and 60.0%, respectively. The calculated sBRCAm/tBRCAm ratio was 23.6% (13/55), and the prevalence of gBRCA variant of uncertain significance was 3.9%. These results suggest gBRCA testing alone cannot clearly identify the best course of treatment, highlighting the importance of sBRCA testing in Japan. The present results also suggest that testing for tBRCA and HRD should be encouraged in advanced ovarian cancer patients to drive precision medicine.

Current status of hereditary breast and ovarian cancer practice among gynecologic oncologists in Japan: a nationwide survey by the Japan Society of Gynecologic Oncology (JSGO)

The practices pertaining to hereditary breast and ovarian cancer (HBOC) in Japan have been rapidly changing owing to the clinical development of poly(ADP-ribose) polymerase inhibitors, the increasing availability of companion diagnostics, and the broadened insurance coverage of HBOC management from April 2020. A questionnaire of gynecologic oncologists was conducted to understand the current status and to promote the widespread standardization of future HBOC management. A Google Form questionnaire was administered to the members of the Japan Society of Gynecologic Oncology. The survey consisted of 25 questions in 4 categories: respondent demographics, HBOC management experience, insurance coverage of HBOC management, and educational opportunities related to HBOC. A total of 666 valid responses were received. Regarding the prevalence of HBOC practice, the majority of physicians responded in the negative and required human resources, information sharing and educational opportunities, and expanded insurance coverage to adopt and improve HBOC practice. Most physicians were not satisfied with the educational opportunities provided so far, and further expansion was desired. They remarked on the psychological burdens of many HBOC managements. Physicians reported these burdens could be alleviated by securing sufficient time to engage in HBOC management, creating easy-to-understand explanatory material for patients, collaboration with specialists in genetic medicine, and educational opportunities. Gynecologic oncologists in Japan are struggling to deal with psychological burdens in HBOC practice. To promote the clinical practice of HBOC management, there is an urgent need to strengthen human resources and improve educational opportunities, and expand insurance coverage for HBOC management.

Efficacy and safety of olaparib maintenance monotherapy for Japanese patients with platinum-sensitive relapsed ovarian, fallopian tube, and primary peritoneal cancer

Olaparib maintenance therapy for platinum-sensitive relapsed ovarian cancer has been approved in Japan since April 2018. Here, we report the experience administering this therapy in our hospital, with the aim of evaluating efficacy and safety in the Japanese population. The study included 52 patients with platinum-sensitive relapsed ovarian, fallopian tube, and primary peritoneal cancer. All patients started olaparib at a dose of 300 mg twice daily. Information about treatment efficacy and adverse effects was collected retrospectively from medical records. Median age was 58 years old (range: 33-80), and 82.7% of the patients were diagnosed with high-grade serous carcinoma. Sixteen patients (30.8%) possessed the BRCA1/2 pathogenic variant (15 germline and 1 tissue), 3 (5.8%) possessed variants of unknown significance (2 germline and 1 tissue), 16 (30.8%) possessed wild type, and 17 (32.7%) were not analyzed. Median progression-free survival was 15.3 months (95% CI 9.0-21.6). Patients with BRCA1/2 pathogenic variants showed significantly longer PFS than patients with wild-type BRCA1/2 (p = 0.007). Disease progression caused 34 cases to discontinue olaparib. Eighteen (34.6%) individuals exhibited ≥ grade 3 anemia, although they recovered in response to appropriate management. One patient discontinued olaparib because of prolonged renal dysfunction. Another patient presented with grade 3 fatigue, but recovered after 2 weeks of interruption and continued olaparib treatment. Olaparib maintenance therapy for platinum-sensitive recurrent ovarian cancer in the Japanese population is sufficiently safe and no less effective than reports from previous studies.

Significance of PD-L1 expression in carbon-ion radiotherapy for uterine cervical adeno/adenosquamous carcinoma

Programmed cell death-ligand 1 (PD-L1) is expressed in tumor cells and has been shown to predict clinical outcomes of several types of malignancies. The aim of this study was to investigate the effects of carbon-ion (C-ion) beam irradiation on PD-L1 expression in human uterine cervical adeno/adenosquamous carcinoma (UCAA) cells and clinical samples and to identify the prognostic factors for outcomes after C-ion radiotherapy (CIRT). The effects of C-ion irradiation on PD-L1 expression in human UCAA and cervical squamous cell carcinoma cells were examined by flow cytometry. We examined PD-L1 expression in UCAA biopsy specimens from 33 patients before CIRT started (pre-CIRT) and after 12 Gy (relative biological effectiveness [RBE]) irradiation (post-12Gy-C) in 4 fractions of CIRT to investigate the correlation between PD-L1 status and clinical outcomes. The PD-L1 expression was upregulated by C-ion beam in a dose-dependent manner in HeLa and SiHa cells through phosphorylated Chk1. The overall frequencies of pre-CIRT and post-12Gy-C PD-L1 positivity were 45% (15/33) and 67% (22/33), respectively. The post-12Gy-C PD-L1 expression was significantly elevated compared to the pre-CIRT PD-L1 expression. There was no significant relationship between the pre-CIRT PD-L1 status and clinical outcomes, such as local control (LC), progression-free survival (PFS), and overall survival (OS). However, the post-12Gy-C PD-L1 expression had better correlation with PFS, but not with LC and OS. CIRT can induce PD-L1 expression in UCAA and we propose that PD-L1 expression after starting CIRT may become as a predictive prognostic marker in CIRT for UCAA.

Association between hospital treatment volume and survival of women with gynecologic malignancy in Japan: a JSOG tumor registry-based data extraction study

Associations between hospital treatment volume and survival outcomes for women with 3 types of gynecologic malignancies, and the trends and contributing factors for high-volume centers were examined. The Japan Society of Obstetrics and Gynecology tumor registry databased retrospective study examined 206,845 women with 80,741, 73,647, and 52,457 of endometrial, cervical, and ovarian tumor, respectively, who underwent primary treatment in Japan between 2004 and 2015. Associations between the annual treatment volume and overall survival (OS) for each tumor type were examined using a multivariable Cox proportional hazards model with restricted cubic splines. Institutions were categorized into 3 groups (low-, moderate-, and high-volume centers) based on hazard risks. Hazard ratio (HR) for OS each the 3 tumors decreased with hospital treatment volume. The cut-off points of treatment volume were defined for high- (≥50, ≥51, and ≥27), moderate- (20-49, 20-50, and 17-26), and low-volume centers (≤19, ≤19, and ≤16) by cases/year for endometrial, cervical, and ovarian tumors, respectively. Multivariate analysis revealed younger age, rare tumor histology, and initial surgical management as contributing factors for women at high-volume centers (all, p<0.001). The proportion of high-volume center treatments decreased, whereas low-volume center treatments increased (all p<0.001). Treatment at high-volume centers improved OS than that at other centers (adjusted HR [aHR]=0.83, 95% confidence interval [CI]=0.78-0.88; aHR=0.78, 95% CI=0.75-0.83; and aHR=0.90, 95% CI=0.86-0.95 for endometrial, cervical, and ovarian tumors). Hospital treatment volume impacted survival outcomes. Treatments at high-volume centers conferred survival benefits for women with gynecologic malignancies. The proportion of treatments at high-volume centers have been decreasing recently.

The trend and outcome of postsurgical therapy for high-risk early-stage cervical cancer with lymph node metastasis in Japan: a report from the Japan Society of Gynecologic Oncology (JSGO) guidelines evaluation committee

The Japan Society of Gynecologic Oncology published the first guidelines for the treatment of cervical cancer in 2007. The aim of this research was to evaluate the influence of the introduction of the first guideline on clinical trends and outcomes of patients with early-stage cervical cancer who underwent surgery. This analysis included 9,756 patients who were diagnosed based on the pathological Tumor-Node-Metastasis (pTNM) classification (i.e., pT1b1, pT1b2, pT2b and pN0, pN1, pNX) and received surgery as a primary treatment between 2004 and 2009. Data of these patients were retrospectively reviewed, and clinicopathological trends were assessed. The influence of the introduction of the guideline on survival was determined by using a competing risk model. For surgery cases, the estimated subdistribution hazard ratio (HR) by the competing risk model for the influence of the guideline adjusted for age, year of registration, pT classification, pN classification, histological type, and treatment methods was 1.024 (p=0.864). Following the introduction of the first guideline in 2007, for patients with lymph node metastasis, the use of chemotherapy (CT) as a postsurgical therapy increased, whereas that of concurrent chemoradiotherapy (CCRT)/radiotherapy (RT) decreased (p<0.010). For pN1 cases, the estimated subdistribution HR by the competing risk model for the influence of the guideline was 1.094 (p=0.634). There was no significance in the postsurgical therapy between CT and CCRT/RT (p=0.078). Survival of surgical cases was not improved by the introduction of the guidelines. It is necessary to consider more effective postsurgical therapy for high-risk early-stage cervical cancer.

Incidence of fistula occurrence in patients with cervical cancer treated with bevacizumab: data from real-world clinical practice

Abstract Background This study aimed to determine the incidence of pelvic fistulas in cervical cancer patients treated with bevacizumab in Japanese clinical practice. Methods A post-marketing surveillance (PMS) study was conducted between June 2016 and February 2018 to survey physicians who treated advanced or recurrent cervical cancer patients with bevacizumab (according to the product label). The clinical/treatment status of patients with pelvic fistulas was assessed in an additional retrospective case series study. Results 142 patients were included in the PMS study (median age 51 years; 66.9% squamous cell carcinoma; 66.2% recurrent cervical cancer; 64.1% previous radiotherapy). Patients received a median of seven bevacizumab doses. Six patients, all of whom had a history of pelvic irradiation, developed seven fistulas (4.2%; 95% confidence interval, 1.56–8.96), and five patients had also undergone pelvic surgery. The case series study of the patients who developed fistulas indicated that three patients had high cumulative bladder and rectal doses of radiation, and two of them had undergone salvage re-irradiation for pelvic recurrence. The other three patients underwent both radical hysterectomy and adjuvant radiotherapy, but did not receive an excessive radiation dose to the bladder or rectum. Conclusions This study found that the upper limit of the 95% confidence interval for pelvic fistula incidence did not exceed the incidence reported in the GOG 240 study. To ensure an adequate benefit-risk assessment of bevacizumab in cervical cancer patients, a comprehensive evaluation of prior treatment is essential and the possibility of unexpected fistulas, even after careful evaluation, should be considered.

Development of a prognostic prediction support system for cervical intraepithelial neoplasia using artificial intelligence-based diagnosis

Human papillomavirus subtypes are predictive indicators of cervical intraepithelial neoplasia (CIN) progression. While colposcopy is also an essential part of cervical cancer prevention, its accuracy and reproducibility are limited because of subjective evaluation. This study aimed to develop an artificial intelligence (AI) algorithm that can accurately detect the optimal lesion associated with prognosis using colposcopic images of CIN2 patients by utilizing objective AI diagnosis. We identified colposcopic findings associated with the prognosis of patients with CIN2. We developed a convolutional neural network that can automatically detect the rate of high-grade lesions in the uterovaginal area in 12 segments. We finally evaluated the detection accuracy of our AI algorithm compared with the scores by multiple gynecologic oncologists. High-grade lesion occupancy in the uterovaginal area detected by senior colposcopists was significantly correlated with the prognosis of patients with CIN2. The detection rate for high-grade lesions in 12 segments of the uterovaginal area by the AI system was 62.1% for recall, and the overall correct response rate was 89.7%. Moreover, the percentage of high-grade lesions detected by the AI system was significantly correlated with the rate detected by multiple gynecologic senior oncologists (r=0.61). Our novel AI algorithm can accurately determine high-grade lesions associated with prognosis on colposcopic images, and these results provide an insight into the additional utility of colposcopy for the management of patients with CIN2.

Ancient Evolutionary History of Human Papillomavirus Type 16, 18 and 58 Variants Prevalent Exclusively in Japan

Human papillomavirus (HPV) is a sexually transmitted virus with an approximately 8-kilo base DNA genome, which establishes long-term persistent infection in anogenital tissues. High levels of genetic variations, including viral genotypes and intra-type variants, have been described for HPV genomes, together with geographical differences in the distribution of genotypes and variants. Here, by employing a maximum likelihood method, we performed phylogenetic analyses of the complete genome sequences of HPV16, HPV18 and HPV58 available from GenBank (n = 627, 146 and 157, respectively). We found several characteristic clusters that exclusively contain HPV genomes from Japan: two for HPV16 (sublineages A4 and A5), one for HPV18 (sublineage A1) and two for HPV58 (sublineages A1 and A2). Bayesian phylogenetic analyses of concatenated viral gene sequences showed that divergence of the most recent common ancestor of these Japan-specific clades was estimated to have occurred ~98,000 years before present (YBP) for HPV16 A4, ~39,000 YBP for HPV16 A5, ~38,000 YBP for HPV18 A1, ~26,000 for HPV58 A1 and ~25,000 YBP for HPV58 A2. This estimated timeframe for the divergence of the Japan-specific clades suggests that the introduction of these HPV variants into the Japanese archipelago dates back to at least ~25,000 YBP and provides a scenario of virus co-migration with ancestral Japanese populations from continental Asia during the Upper Paleolithic period.

Clinical availability and characteristics of multigene panel testing for recurrent/advanced gynecologic cancer

Japan's health insurance covers multigene panel testing. This study aimed to determine the potential availability and utility of gene panel testing clinically in gynecologic oncology. We analyzed the characteristics of patients with gynecologic cancer who underwent gene panel testing using FoundationOne Out of 102 patients analyzed, 32, 18, 43, 8, and 1 had cervical, endometrial, ovarian cancers, sarcoma, and vaginal cancer, respectively. Druggable gene alteration was found in 70 patients (68.6%; 21 with cervical cancer, 15 with endometrial cancer, 28 with ovarian cancer, 5 with sarcoma, and 1 with other). The most common druggable gene alteration was PIK3CA mutation (n = 21), followed by PTEN mutation (n = 12) and high tumor mutation burden (TMB-H) (n = 11). TMB-H was detected in 5 patients with cervical cancer, 5 with endometrial cancer, and 1 with endometrial stromal sarcoma. Eleven patients (10.8%) received molecularly targeted therapy according to their gene aberrations. Gene panel testing was mostly performed when the second-line treatment was ineffective. Of all 102 patients, 60 did not have recommended treatment, and 15 died or had worsened conditions before obtaining the test results. Through multigene panel testing, although many patients had druggable gene alterations, 10.8% of them received the recommended treatment. TMB-H was mainly observed in cervical/endometrial cancer, suggesting its potential as a therapeutic biomarker of immune checkpoint inhibitors. Furthermore, patients' prognosis and performance status should be considered before performing the test.

Phase I and II randomized clinical trial of an oral therapeutic vaccine targeting human papillomavirus for treatment of cervical intraepithelial neoplasia 2 and 3

Abstract Background Although many human papillomavirus (HPV)–targeted therapeutic vaccines have been examined for efficacy in clinical trials, none have been translated into clinical use. These previous agents were mostly administered by intramuscular or subcutaneous injection to induce systemic immunity. We investigated the safety and therapeutic efficacy of an HPV-16 E7-expressing lacticaseibacillus-based oral vaccine. Methods In a double-blind, placebo-controlled, randomized trial, a total of 165 patients with HPV-16–positive high-grade cervical intraepithelial neoplasia 2 and 3 were assigned to orally administered placebo or low, intermediate, or high doses of IGMKK16E7 (lacticaseibacillus paracasei expressing cell surface, full-length HPV-16 E7). In the 4 groups, IGMKK16E7 or placebo was administered orally at weeks 1, 2, 4, and 8 postenrollment. The primary outcomes included histopathological regression and IGMKK16E7 safety. Results In per-protocol analyses, histopathological regression to normal (complete response) occurred in 13 (31.7%) of 41 high-dose recipients and in 5 (12.5%) of 40 placebo recipients (rate difference = 19.2, 95% confidence interval [CI] = 0.5 to 37.8). In patients positive for HPV-16 only, the clinical response rate was 40.0% (12 of 30) in high-dose recipients and 11.5% (3 of 26) in recipients of placebo (rate difference = 28.5, 95% CI = 4.3 to 50.0). There was no difference in adverse events that occurred in the high-dose and placebo groups (P = .83). The number of HPV-16 E7–specific interferon-γ producing cells within peripheral blood increased with level of response (stable disease, partial, and complete responses; P = .004). The regression to normal (complete response) rates among recipients with high levels of immune response were increased in a dose-dependent manner. Conclusion This trial demonstrates safety of IGMKK16E7 and its efficacy against HPV-16–positive cervical intraepithelial neoplasia 2 and 3. IGMKK16E7 is the first oral immunotherapeutic vaccine to show antineoplastic effects. Trial registration jRCT2031190034.

The 2020 Japan Society of Gynecologic Oncology guidelines for the treatment of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer

The fifth edition of the Japan Society of Gynecologic Oncology guidelines for the treatment of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer was published in 2020. The guidelines contain 6 chapters-namely, (1) overview of the guidelines; (2) epithelial ovarian cancer, fallopian tube cancer, and primary peritoneal cancer; (3) recurrent epithelial ovarian cancer, fallopian tube cancer, and primary peritoneal cancer; (4) borderline epithelial tumors of the ovary; (5) malignant germ cell tumors of the ovary; and (6) malignant sex cord-stromal tumors. Furthermore, the guidelines comprise 5 algorithms-namely, (1) initial treatment for ovarian cancer, fallopian tube cancer, and primary peritoneal cancer; (2) treatment for recurrent ovarian cancer, fallopian tube cancer, and primary peritoneal cancer; (3) initial treatment for borderline epithelial ovarian tumor; (4) treatment for malignant germ cell tumor; and (5) treatment for sex cord-stromal tumor. Major changes in the new edition include the following: (1) revision of the title to "guidelines for the treatment of ovarian cancer, fallopian tube cancer, and primary peritoneal cancer"; (2) involvement of patients and general (male/female) participants in addition to physicians, pharmacists, and nurses; (3) clinical questions (CQs) in the PICO format; (4) change in the expression of grades of recommendation and level of evidence in accordance with the GRADE system; (5) introduction of the idea of a body of evidence; (6) categorization of references according to research design; (7) performance of systematic reviews and meta-analysis for three CQs; and (8) voting for each CQ/recommendation and description of the consensus.

Prognostic significance of para-aortic node metastasis in endometrial cancer: Japanese Gynecologic Oncology Group Study JGOG2043 post hoc analysis

This study aimed to assess the prognostic significance of para-aortic lymphadenectomy (PALX) and para-aortic lymph node metastasis in endometrial cancer (EC) patients at risk of post-operative recurrence. Japanese Gynecologic Oncology Group (JGOG) 2043 was a randomized controlled trial assessing the efficacy of adjuvant chemotherapy in EC patients at risk for post-operative recurrence. A retrospective analysis included patients who underwent pelvic lymphadenectomy (PLX) alone or both PLX and PALX in JGOG2043. Data on positive lymph nodes and other clinicopathological risk factors were collected. PLX and PALX were performed on 402 patients, while PLX alone was conducted on 250 patients. Evaluating the effect of PALX on survival was challenging through a comparison of the outcomes of the 2 cohorts since PALX was predominantly administered to higher-risk patients. Patients with 2 or more metastases in para-aortic nodes exhibited significantly poorer overall survival than those with no or 1 metastasis, respectively (p<0.001, p=0.031). Multivariate analysis revealed that 2 or more metastases in para-aortic nodes is independent risk factors for disease-free survival (hazard ratio [HR]=1.72; 95% confidence interval [CI]=1.10-2.72; p=0.019) and are marginally significant for overall survival (HR=1.58; 95% CI=0.92-2.72; p=0.096) compared to no or a single metastasis. The clinical relevance of PALX was challenging to evaluate in the JGOG2043 cohort; however, the presence of 2 or more para-aortic node metastases was identified as an independent unfavorable prognostic factor in EC patients at risk of recurrence.

Niraparib in Japanese patients with heavily pretreated, homologous recombination-deficient ovarian cancer: final results of a multicenter phase 2 study

To evaluate the long-term efficacy and safety of niraparib in Japanese women with heavily pretreated ovarian cancer. This was the follow-up analysis of a phase 2, multicenter, open-label, single-arm study in Japanese women with homologous recombination-deficient, platinum-sensitive, relapsed, high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who had completed 3-4 lines of chemotherapy and were poly(ADP-ribose) polymerase inhibitor naïve. Participants received niraparib (starting dose, 300 mg) once daily in continuous 28-day cycles until objective disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was confirmed objective response rate (ORR), as assessed using Response Evaluation Criteria in Solid Tumors version 1.1. Safety evaluations included treatment-emergent adverse events (TEAEs). 20 patients were enrolled in the study and included in both efficacy and safety analyses. Median total study duration was 759.5 days. Median dose intensity was 201.3 mg/day. Confirmed ORR was 60.0% (90% confidence interval [CI]=39.4-78.3); 2 patients had complete response and 10 patients had partial response. Median duration of response was 9.9 months (95% CI=3.9-26.9) and the disease control rate was 90.0% (95% CI=68.3-98.8). The most common TEAEs were anemia (n=15), nausea (n=12), and decreased platelet count (n=11). TEAEs leading to study drug dose reduction, interruption, or discontinuation were reported in 16 (80.0%), 15 (75.0%), and 2 patients (10.0%), respectively. The long-term efficacy and safety profile of niraparib was consistent with previous findings in the equivalent population in non-Japanese patients. No new safety signals were identified. ClinicalTrials.gov Identifier: NCT03759600.

Prognostic impact of the number of resected pelvic nodes in endometrial cancer: Japanese Gynecologic Oncology Group Study JGOG2043 post hoc analysis

This study aimed to determine whether the number of resected pelvic lymph nodes (PLNs) affects the prognosis of endometrial cancer (EC) patients at post-operative risk of recurrence. JGOG2043 was a randomized controlled trial to assess the efficacy of three chemotherapeutic regimens as adjuvant therapy in EC patients with post-operative recurrent risk. A retrospective analysis was conducted on 250 patients who underwent pelvic lymphadenectomy alone in JGOG2043. The number of resected and positive nodes and other clinicopathologic risk factors for survival were retrieved. There were 83 patients in the group with less than 20 PLNs removed (group A), while 167 patients had 20 or more PLNs removed (group B). There was no significant difference in patients' backgrounds between the two groups, and the rate of lymph node metastasis was not significantly different. There was a trend toward fewer pelvic recurrences in group B compared with group A (3.5% vs. 9.6%; p=0.050). Although Kaplan-Meier analysis showed no statistically significant difference in survival rates between the two groups (5-year overall survival [OS]=90.3% vs. 84.3%; p=0.199), multivariate analysis revealed that resection of 20 or more nodes is one of the independent prognostic factors (hazard ratio=0.49; 95% confidence interval=0.24-0.99; p=0.048), as well as surgical stage, high-risk histology, and advanced age for OS. Resection of 20 or more PLNs was associated with improved pelvic control and better survival outcomes in EC patients at risk of recurrence who underwent pelvic lymphadenectomy alone and were treated with adjuvant chemotherapy.

Cost-effectiveness analysis of hospital treatment volume and survival outcomes in endometrial cancer in Japan

Hospital treatment volume affects survival in patients with endometrial cancer; notably, initial treatment at high-volume centers improves survival outcomes. Our study assessed the effect of hospital treatment volume on cost-effectiveness and survival outcomes in patients with endometrial cancer in Japan. A decision-analytic model was evaluated using the following variables and their impact on cost-effectiveness: 1) hospital treatment volume (low-, intermediate-, and high-volume centers) and 2) postoperative recurrent risk factors based on pathological findings (high- and intermediate-risk or low-risk). Data were obtained from the Japan Society of Obstetrics and Gynecology database, systematic literature searches, and the Japanese Diagnosis Procedure Combination database. Quality-adjusted life years (QALY) was used as a measure of effectiveness. The model was built from a public healthcare perspective and the impact of uncertainty was assessed using sensitivity analyses. A base-case analysis showed that the incremental cost-effectiveness ratio at high-volume centers was below a willingness-to-pay (WTP) threshold of ¥5,000,000 with a maximum of ¥3,777,830/4.28 QALY for the high- and intermediate-risk group, and ¥2,316,695/4.57 QALY for the low-risk group. Treatment at the high-volume centers showed better efficiency and cost-effectiveness in both strategies compared to intermediate- or low-volume centers. Sensitivity analyses showed that the model outcome was robust to changes in input values. With the WTP threshold, treatment at high-volume centers remained cost-effective in at least 73.6% and 78.2% of iterations for high- and intermediate-risk, and low-risk groups, respectively. Treatment at high-volume centers is the most cost-effective strategy for guiding treatment centralization in patients with endometrial cancer.

35Papers
185Collaborators
Ovarian NeoplasmsEndometrial NeoplasmsNeoplasm Recurrence, LocalCarcinoma, Ovarian EpithelialPrognosisNeoplasm StagingPapillomavirus Infections