Hidetaka Katabuchi

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.

Hemoglobin-induced continuous activation of macrophages in endometriotic cysts: a potential mechanism of endometriosis development and carcinogenesis

Endometriosis is a chronic inflammatory disease. Endometriotic cysts contain hemoglobin (Hb) and infiltrated macrophages, indicating that the metabolism of Hb by macrophages may play an important role in the inflammation of endometriotic cysts. In this study, we investigated the distribution of immune cells and CD163 (Hb receptor)-positive cells in the endometriotic cyst wall using immunohistochemistry. We also examined the role of macrophage activation by Hb on the pathogenesis of endometriotic cysts by measuring the cytokine concentration in the cystic fluids and macrophage-culture supernatant using ELISA. Macrophages were the most prominent immune cells observed in the endometriotic cysts and were differentially distributed in the different histological areas of the cyst wall. The localization of CD163-positive macrophages was restricted to the hemorrhagic and outer areas in the cyst wall. High concentrations of IL-6 and CCL2 were found in the cystic fluids, and inflammatory cytokines (IL-6, TNF-α, and CCL2) were secreted from macrophages on stimulation by Hb. IL-6 is a promotional factor for endometriotic stromal cells and ovarian clear cell carcinoma, the most common histological subtype of endometriosis-related ovarian cancer, hence, the continuous activation of macrophages by Hb could be a potential mechanism underlying endometriosis development and carcinogenesis.

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.

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.

Association of menopause, aging and treatment procedures with positive margins after therapeutic cervical conization for CIN 3: a retrospective study of 8,856 patients by the Japan Society of Obstetrics and Gynecology

The Japan Society of Obstetrics and Gynecology conducted a retrospective multi-institutional survey of patients who underwent cervical conization in Japan. This study aimed to determine the predictive factors for positive surgical margins in cervical intraepithelial neoplasia grade 3 (CIN 3) patients after therapeutic cervical conization and those for positive margins in patients who did not experience recurrence and did not undergo additional treatment. In 2009 and 2013, 14,832 patients underwent cervical conization at 205 institutions in Japan. Of these, 8856 patients who underwent therapeutic conization fulfilled the inclusion criteria. Their histologic findings and clinical outcomes were evaluated based on standard statistical procedures and clinical and demographic characteristics. Negative and positive margins were observed in 7,585 and 1,271 (14.4%) patients, respectively. The predictors of positive margins were menopausal status (p<0.001), loop electrosurgical excision procedure (p<0.001), and Shimodaira-Taniguchi (S-T) conization (p<0.001). Of 1,271 patients with positive margins, 1,060 underwent no additional treatment; among those 1,060 patients, 129 (12.2%) experienced recurrence. The predictors of positive margins in patients who did not undergo additional treatment and did not experience recurrence were age, parity, gravidity, S-T conization, and laser scalpel conization. Menopausal status and treatment procedures were associated with positive margins after therapeutic conization of CIN 3. It is important to understand the characteristics of treatment procedures and select an appropriate procedure for each case. For elderly or menopausal patients with positive margins, immediate additional treatment is recommended.

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.

Impact of COVID‐19 on cervical cancer screening in Japan: A survey of population‐based screening in urban Japan by the Japan Society of Gynecologic Oncology

AbstractAimTo assess the impact of COVID‐19 on cervical cancer screening.MethodThe Japanese Society of Gynecologic Oncology launched COVID‐19 Task Force surveyed the municipalities in urban areas of Japan. Questionnaires were sent to 20 ordinance‐designated cities and 23 wards of Tokyo metropolitan area in Japan via telephone and mail in January 2021. An additional survey was conducted in March and April 2021, counted the monthly checkups in 2020 and, as a control data, the number of monthly checkups in 2019. “The State of Emergency” between April 7 and May 25, 2020, included 13 prefectures. The data collected in this research involved the number of screenings only. The chi‐square test was performed for statistical analysis.ResultsThe number of cancer screenings from March to August, with May being the month with the lowest number of screenings, was less than 50% of that in the previous year. In particular, the drop in the number of cancer screenings in the “Prefectures operating under special safety precautions” was remarkable and significantly lower than that in other Prefectures. However, after August, the number recovered to the usual level, despite the second wave of the pandemic occurring nationwide. The initial “the State of Emergency” caused a significant decrease in the number of people receiving population‐based screenings, but the recovery has been remarkable, and the total number is expected to be the same as in previous years.ConclusionThe initial “the State of Emergency” caused a significant decrease in the number of people receiving population‐based screenings.

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.

Sentinel node navigation surgery in cervical cancer: a systematic review and metaanalysis

Sentinel node navigation surgery (SNNS) is used in clinical practice for the treatment of cervical cancer. This study aimed to elucidate the appropriate sentinel lymph node (SLN) mapping method and assess the safety and benefits of SNNS. We searched the PubMed, Ichushi, and Cochrane Library databases for randomized controlled trials (RCT) and studies on SLN in cervical cancer from January 2012 to December 2020. Two authors independently assessed study quality and extracted data. We quantitatively analyzed the detection rate, sensitivity/specificity, and complications and reviewed information, including the survival data of SLN biopsy (SLNB) without pelvic lymphadenectomy (PLND). The detection rate of SLN mapping in the unilateral pelvis was median 95.7% and 100% and in the bilateral pelvis was median 80.4% and 90% for technetium-99 m (Tc) with/without blue dye (Tc w/wo BD) and indocyanine green (ICG) alone, respectively. The sensitivity and specificity of each tracer were high; the area under the curve of each tracer was 0.988 (Tc w/wo BD), 0.931 (BD w/wo Tc), 0.966 (ICG), and 0.977 (carbon nanoparticle). Morbidities including lymphedema, neurological symptoms and blood loss were associated with PLND. One RCT and five studies all showed SNNS without systematic PLND does not impair recurrence or survival in early-stage cervical cancer with a tumor size ≤ 2-4 cm. Both Tc w/wo BD and ICG are appropriate SLN tracers. SNNS can reduce the morbidities associated with PLND without affecting disease progression in early-stage cervical cancer.

Japan Society of Gynecologic Oncology 2022 guidelines for uterine cervical neoplasm treatment

The Japan Society of Gynecologic Oncology (JSGO) Guidelines 2022 for the Treatment of Uterine Cervical Cancer are revised from the 2017 guideline. This guideline aimed to provide standard care for cervical cancer, indicate appropriate current treatment methods for cervical cancer, minimize variances in treatment methods among institutions, improve disease prognosis and treatment safety, reduce the economic and psychosomatic burden of patients by promoting the performance of appropriate treatment, and enhance mutual understanding between patients and healthcare professionals. The guidelines were prepared through the consensus of the JSGO Guideline Committee, based on a careful review of evidence gathered through the literature searches and the medical health insurance system and actual clinical practice situations in Japan. The guidelines comprise seven chapters and 5 algorithms. The main features of the 2022 revision are as follows: 1) added discussed points at the final consensus meeting; 2) revised the treatment methods based on the International Federation of Gynecology and Obstetrics 2018 staging system; 3) examined minimally invasive surgery based on Laparoscopic Approach to Cervical Cancer trial; 4) added clinical question (CQ) for treatments of rare histological types, gastric type, and small-cell neuroendocrine carcinoma; 5) added CQ for intensity-modulated radiation therapy; 6) added CQ for cancer genomic profiling test; and 7) added CQ for cancer survivorship. Each recommendation is accompanied by a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSGO Guidelines 2022 for the Treatment of Uterine Cervical Cancer.

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.

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.