Masato Yoshihara

Mesothelial cells promote peritoneal invasion and metastasis of ascites-derived ovarian cancer cells through spheroid formation

Patients with epithelial ovarian cancer (EOC) are often diagnosed with peritoneal metastasis and ascites, the accumulation of intraperitoneal fluid containing nonmalignant cells. However, the interactions between EOC and nonmalignant cells before peritoneal metastasis remain unclear. To investigate this, whole EOC spheroids were observed using a multiphoton microscope, and their invasion ability was assessed. Mesothelial cells were identified as notable components of ascites through morphological assessment, immunohistochemical/immunofluorescence staining, and single-cell RNA sequencing analyses. Almost all EOC cells were spheroids, with 60% containing mesothelial cells. EOC cells quickly generate aggregated spheroids with mesothelial cells, and these aggregated cancer-mesothelial spheroids (ACMSs) invade collagen or mesothelial layers. Mesothelial cells forming ACMSs initiated the invasion. RNA sequencing analysis revealed marked RNA expression changes in mesothelial cells, whereas the changes in EOC cells were minor. Transforming growth factor–β1–stimulated mesothelial cells showed increased invadopodium formation along with fascin-1 up-regulation. These findings suggest that EOC cells alter mesothelial cells through ACMSs, thereby elucidating the rapid spread of EOC in the abdominal cavity.

Long-term prognostic significance of ascites cytology in ovarian cancer cases in which R0 resection was achieved in the initial surgery: a multi-institutional retrospective cohort study

Abstract Background In ovarian cancer (OvCa), achieving complete resection (RO) in initial surgery is crucial for improving prognosis. However, patients with undetected microscopic metastasis post-RO surgery often have poorer outcomes. This study explores prognostic factors for OvCa patients who underwent RO surgery, focusing on the role of ascites cytology as an indicator of microscopic peritoneal metastasis. Methods We analyzed data from 975 OvCa cases in the Tokai Ovarian Tumor Study Group database (1986–2019). Excluding patients without chemotherapy or with distant metastasis, we examined prognostic factors using Cox regression analysis. Propensity score (PS) methods balanced the cytology-positive and -negative groups, with subgroup analysis for clinical stage and ascites volume. Results Multivariate analysis identified FIGO stage III and positive ascites cytology as poor prognostic factors for overall and progression-free survival. After PS adjustment, positive ascites cytology also shortened progression-free intervals post-recurrence, especially in cases with peritoneal or lymph node metastasis. Subgroup analysis revealed a more substantial prognostic impact of positive ascites cytology in early-stage cases. Conclusion The present results suggest that in OvCa patients with the R0 status, the presence of tumor cells in ascites is an independent negative prognostic factor and may be an indicator of peritoneal micro-metastasis.

Vitamin D derivatives inhibit mesenchymal transition of mesothelial cells and mitigate peritoneal dissemination of ovarian cancer

Ovarian cancer (OvCa) is a leading cause of gynecological cancer-related mortality, primarily due to peritoneal dissemination, which facilitates metastasis in the abdominal cavity. This study explored the potential of vitamin D and its synthetic derivatives in mitigating peritoneal dissemination by modulating the behavior of mesothelial cells (MCs). Vitamin D, through its receptor (VDR), is known to influence cancer progression, and our findings demonstrate that vitamin D derivatives can inhibit mesenchymal transition of MCs induced by TGF-β1, a key driver of peritoneal dissemination. This study used patient-derived primary MCs and in vivo mouse model to assess the effects of vitamin D derivatives on cell morphology, gene expression, and OvCa cell adhesion. Two vitamin D derivatives, VDR agonist, showed significant efficacy in maintaining epithelial-like MC morphology, reducing TGF-β1-induced changes, and inhibiting OvCa cell adhesion to the peritoneum, similar to calcitriol. Conversely, the VDR antagonist derivative induced MC apoptosis, highlighting the essential role of vitamin D in MC survival. These findings suggest that vitamin D derivatives could serve as promising therapeutic agents for OvCa by preserving peritoneal homeostasis and preventing metastasis. Further research is required to explore a broader range of derivatives and their underlying molecular mechanisms.

Histology-specific long-term oncologic outcomes in patients with epithelial ovarian cancer who underwent complete tumor resection: The implication of occult seeds after initial surgery

Objective Assessing the histology-specific prognosis of epithelial ovarian cancer (OvCa) is clinically challenging, especially in a patient population with a favorable prognosis. This study investigated the histology-specific long-term oncologic outcomes in OvCa patients who underwent complete tumor resection using a large-scale patient cohort form multiple institutions under a central pathological review system. Methods A regional multi-institutional study was conducted from 1986 to 2019. Of the 4,898 patients with ovarian tumors enrolled, 1,175 patients who underwent complete tumor resection were classified into three classes based on clinically important prognostic factors: stage, cytology, ascites volume. For each class category, the effect of histology types on recurrence-free survival, the site of recurrence, and post-recurrence survival was evaluated. Results Recurrence-free survival varied significantly across different histologies (P < 0.001). The risk of recurrence was higher in serous carcinoma compare to other histologies (P < 0.001). The site of tumor recurrence varied by the histology type. Multinominal logistic regression analysis revealed that mucinous histology had a significantly higher likelihood of developing recurrent tumors at distant sites from the peritoneum compared to other histologies (P = 0.002). Conversely, serous histology was associated with better post-recurrence survival (Log-rank P < 0.001). Conclusions Long-term oncologic outcomes significantly differ by histology type in OvCa patients who have undergone complete tumor resection at the initial surgery. A careful evaluation of the clinical background is necessary for these patients, and further clinical research into individualized treatment approaches is essential.

Chondroitin Sulfate Proteoglycan 4 Provides New Treatment Approach to Preventing Peritoneal Dissemination in Ovarian Cancer

Most epithelial ovarian cancer (EOC) patients are diagnosed with peritoneal dissemination. Cellular interactions are an important aspect of EOC cells when they detach from the primary site of the ovary. However, the mechanism remains underexplored. Our study aimed to reveal the role of chondroitin sulfate proteoglycan 4 (CSPG4) in EOC with a major focus on cell–cell interactions. We examined the expression of CSPG4 in clinical samples and cell lines of EOC. The proliferation, migration, and invasion abilities of the CSPG4 knockdown cells were assessed. We also assessed the role of CSPG4 in spheroid formation and peritoneal metastasis in an in vivo model using sh-CSPG4 EOC cell lines. Of the clinical samples, 23 (44.2%) samples expressed CSPG4. CSPG4 was associated with a worse prognosis in patients with advanced EOC. Among the EOC cell lines, aggressive cell lines, including ES2, expressed CSPG4. When CSPG4 was knocked down using siRNA or shRNA, the cell proliferation, migration, and invasion abilities were significantly decreased compared to the control cells. Proteomic analyses showed changes in the expression of proteins related to the cell movement pathways. Spheroid formation was significantly inhibited when CSPG4 was inhibited. The number of nodules and the tumor burden of the omentum were significantly decreased in the sh-CSPG4 mouse models. In the peritoneal wash fluid from mice injected with sh-CSPG4 EOC cells, significantly fewer spheroids were present. Reduced CSPG4 expression was observed in lymphoid enhancer-binding factor 1-inhibited cells. CSPG4 is associated with aggressive features of EOC and poor prognosis. CSPG4 could be a new treatment target for blocking peritoneal metastasis by inhibiting spheroid formation.

Update on the oncologic and obstetric outcomes of medroxyprogesterone acetate treatment for atypical endometrial hyperplasia and endometrial cancer

Abstract Aims To evaluate the safety and effectiveness of high‐dose oral medroxyprogesterone acetate (MPA) therapy as a fertility‐sparing treatment for patients diagnosed with atypical endometrial hyperplasia (AEH) and endometrioid carcinoma G1 without myometrial invasion (G1EC). Particular attention was given to the extended administration and readministration of MPA for patients with persistent disease following initial treatment and those with recurrence. Methods We conducted a retrospective analysis of data from 79 patients who underwent daily oral MPA treatment between 2005 and 2024 at Nagoya University Hospital. Patient characteristics, treatment outcomes, factors contributing to recurrence, and post‐MPA therapy pregnancies were examined. Results MPA therapy achieved a remarkable complete response (CR) rate of 91.1%. The median time to achieve CR was 26.0 and 40.0 weeks for AEH and G1EC patients, respectively. Importantly, 27 patients (39.7%) attained CR after more than 6 months of treatment, including 8 patients (11.8%) who achieved CR after more than a year of treatment. The recurrence rates were 52.9% for AEH and 64.7% for G1EC. Twenty eight patients resumed MPA treatment, and 23 achieved second CR. Notably, recurrence was not associated with clinical factors such as age, body mass index, or post‐CR pregnancy. Among patients who attempted pregnancy after achieving CR, 22 live births were successfully achieved. Conclusions High‐dose oral MPA therapy demonstrated both safety and efficacy for preserving fertility in patients with AEH and G1EC, resulting in a high CR rate. MPA extension and readministration proved to be beneficial strategies for managing patients with recurrence and persistent disease following initial treatment.

Spatial distribution of tumor‐resident macrophages as predictive biomarkers in endometrial cancer

Abstract Background To investigate the role of CD47 expression and its relationship with tumor‐resident macrophages, specifically at the tumor margin, in patients with type II endometrial cancer. This study aims to elucidate whether CD47 could serve as a prognostic marker and to understand the dynamics between CD47 and macrophages, which could inform new therapeutic strategies. Methods A retrospective cohort study was conducted involving 75 patients of type II endometrial. Immunohistochemical analysis was performed to assess CD47 expression and macrophage markers (CD68 and CD163). Results The study found no direct correlation between CD47 expression levels and overall survival ( p  = 0.32), challenging its role as an independent prognostic marker in type II endometrial cancer. The higher expression of CD47 had significantly less incidence of endometrioid carcinoma G3 ( p  = 0.047). The negative correlation between CD47 H‐score and the density of CD68‐positive macrophages at tumor margin was statistically significant ( p  = 0.049). A high density of CD68‐positive macrophages at the tumor margin but a low density of CD163‐positive macrophages at the tumor margin were associated with poorer prognosis ( p  = 0.036). Conclusions The complex interaction between CD47 and macrophages, particularly at the tumor margin, suggests new avenues for targeted therapy in type II endometrial cancer.

Factors affecting the long‐term prognosis of patients in the AYA generation with epithelial ovarian cancer: A multicenter propensity score matching analysis

AbstractObjectiveOvarian carcinoma (OvCa) is more common in the elderly, but also affects the adolescent and young adult (AYA) generation, which refers to those aged 15–39 years. Although the characteristics of OvCa may differ between AYAs and non‐AYAs, limited information is currently available on differences in prognostic factors. Therefore, we herein investigated prognostic factors for and the prognosis of OvCa in AYAs. We also examined the prognostic impact of fertility‐sparing surgery in a subgroup analysis.MethodsWe retrospectively collected data on 4897 patients with OvCa from the databases of multiple institutions and ultimately included 1161 patients with epithelial ovarian cancer (EOC). We performed a survival analysis to compare AYAs and non‐AYAs with backgrounds that conformed to those of AYAs using the propensity score (PS) matching method. A Cox regression analysis was also conducted to evaluate each predictor of recurrence‐free survival (RFS) and overall survival (OS) in the original population. As a subgroup analysis, a multivariate analysis stratified by the AYA and non‐AYA generations was performed.ResultsIn total, 119 AYA patients were included in this study. After PS adjustments, no significant differences were observed in RFS or OS between AYAs and non‐AYAs. Prognostic factors differed between AYAs and non‐AYAs, particularly in histology and cytology. A multivariate analysis stratified by the AYA and non‐AYA generations described that uterine‐preserving surgery (UPS) did not have a significant impact on the prognosis of AYAs or non‐AYAs. In cases with recurrence, no significant differences were observed in RFS and recurrent sites in the two groups.ConclusionCharacteristic prognostic factors for EOC in AYAs were identified. The present results indicate the limited prognostic impact of UPS for EOC in AYAs.

The sarcopenia index measured using the lumbar paraspinal muscle is associated with prognosis in endometrial cancer

Abstract Objective The number of type-II endometrial cancer patients has been increasing and the prognosis is not favorable. We aim to investigate whether sarcopenia index in any of several different muscles could serve as a novel biomarker of prognosis in patients with type-II endometrial cancer. Methods We retrospectively investigated a total of 194 patients at four hospitals. Ninety patients were treated as derivation set and the other 104 patients as validation set. Using preoperative computed tomography images, we measured the horizontal cross-sectional area at the third lumbar spine level: the (i) psoas major, (ii) iliac and (iii) paraspinal muscle. The clinical information including recurrence-free survival and overall survival were retrospectively collected. These results were validated with external data sets of three hospitals. Results The median values of the sarcopenia index (cm2/m2) ± standard deviation with the first data of 90 patients using the psoas, iliac and paraspinal muscle were 3.4 ± 1.0, 1.7 ± 0.6 and 12.6 ± 3.2, respectively. In univariate analyses, the sarcopenia indexes measured using the psoas or paraspinal muscle were associated with recurrence-free survival and overall survival. On the other hand, in multivariate analyses, only the sarcopenia index using paraspinal muscle was significantly related to recurrence-free survival (hazard ratio = 3.78, 95% confidence intervals = 1.29–5.97, P = 0.009) and overall survival (hazard ratio = 3.13, 95% confidence interval = 1.18–8.26, P = 0.022). Paraspinal sarcopenia index was also related to overall survival (hazard ratio = 3.74, 95% confidence interval = 1.31–10.72, P = 0.014) even in patients with advanced stage. Serum albumin was significantly correlated with the sarcopenia index (P = 0.012). Within the analysis of the validation set, sarcopenia index using paraspinal muscle was related to recurrence-free survival (hazard ratio = 2.06, P = 0.045) in multivariate analysis and recurrence-free survival (P = 0.009) in patients with advanced stage. Conclusions The sarcopenia index using the paraspinal muscle, not psoas, could be a suitable index to predict recurrence-free survival and overall survival in patients with type-II endometrial cancer even in advanced stage.

Proton beam therapy for the isolated recurrence of endometrial cancer in para-aortic lymph nodes: a case report

Abstract Background Proton beam therapy penetrates tumor tissues with a highly concentrated dose. It is useful when normal structures are too proximate to the treatment target and, thus, may be damaged by surgery or conventional photon beam therapy. However, proton beam therapy has only been used to treat recurrent endometrial cancer in a few cases; therefore, its effectiveness remains unclear. Case presentation We herein report a case of the isolated recurrence of endometrial cancer in the para-aortic lymph nodes in a 59-year-old postmenopausal woman that was completely eradicated by proton beam therapy. The patient was diagnosed with stage IIIC2 endometrial cancer and treated with 6 courses of doxorubicin (45 mg/m2) and cisplatin (50 mg/m2) in adjuvant chemotherapy. Fifteen months after the initial therapy, the isolated recurrence of endometrial cancer was detected in the para-aortic lymph nodes. The site of recurrence was just under the left renal artery. Due to the potential risks associated with left kidney resection due to the limited surgical space between the tumor and left renal artery, proton beam therapy was administered instead of surgery or conventional photon beam therapy. Following proton beam therapy, the complete resolution of the recurrent lesion was confirmed. No serious complications occurred during or after treatment. There have been no signs of recurrence more than 7 years after treatment. Conclusions Proton beam therapy is a potentially effective modality for the treatment of recurrent endometrial cancer where the tumor site limits surgical interventions and the use of conventional photon beam therapy.

Does complete-staging lymphadenectomy improve survival outcomes in stage I endometrioid epithelial ovarian carcinoma? A multi-institutional retrospective study with propensity score-weighted analysis

AbstractBackgroundWe investigated the prognostic impact of complete-staging lymphadenectomy on patients with clinically apparent Stage I endometrioid epithelial ovarian carcinoma.MethodsWe conducted a regional multi-institutional retrospective study between 1986 and 2018. Amongst 4897 patients with malignant ovarian tumours diagnosed under central pathological review, 259 women with Stage I endometrioid epithelial ovarian carcinoma were eligible. We evaluated differences in survival of patients with both pelvic and para-aortic lymphadenectomy (Group A) and those with only pelvic lymphadenectomy and/or clinical lymph node evaluation (Group B). To analyse the therapeutic effects, the baseline imbalance between patients with both pelvic and para-aortic lymphadenectomy and others was adjusted with an inverse probability of treatment weighting using propensity score involving independent clinical variables.ResultsIn total, 145 patients (56.0%) received both pelvic and para-aortic lymphadenectomy. With propensity score-based adjustment, estimated survival was better in Group A compared with that in Group B but not significant. Pelvic and para-aortic lymphadenectomy also led to no significant improvement of overall survival in most of the subgroups. However, point estimations of the hazard ratio for lymphadenectomy in patients with an age of 45 or younger (hazard ratio, 0.304; 95% confidence interval, 0.094–0.982), a Grade 1–2 (hazard ratio, 0.441; 95% confidence interval, 0.204–0.954) and T1c2–3 tumour (hazard ratio, 0.449; 95% confidence interval, 0.164–1.231) were better compared with those with the opposite characteristics.ConclusionsComplete-staging lymphadenectomy was not a significant prognostic factor in patients with Stage I endometrioid epithelial ovarian carcinoma, where we still need to explore appropriate candidate for the procedure.

Tumor growth direction predicts surgical difficulty in large uterine fibroids: A retrospective imaging‐based study

Abstract Objective To identify preoperative imaging features associated with retroperitoneal growth of large uterine fibroids and evaluate their impact on surgical outcomes. Methods This retrospective study included 20 patients who underwent hysterectomy for uterine fibroids measuring ≥10 cm between 2014 and 2024. Preoperative CT or MRI was evaluated for four features: bladder displacement, sigmoid colon deviation, cecal displacement, and hydronephrosis. Tumor growth direction (intraperitoneal vs. retroperitoneal) was determined intraoperatively. Operative time, blood loss, and complications were compared between groups. Results Eight tumors exhibited retroperitoneal growth. Bladder displacement, cecal shift, sigmoid colon deviation, and hydronephrosis were significantly more common in retroperitoneal cases (all p  < 0.05). Retroperitoneal tumors were associated with significantly greater median blood loss (1591 mL vs. 651 mL, p  = 0.043), although operative time did not differ significantly (301 vs. 232 min, p  = 0.237). Organ injury or resection occurred only in the retroperitoneal group. A bubble plot illustrated the trend of increased surgical burden in retroperitoneal cases. Conclusion Retroperitoneal growth of large uterine fibroids is associated with increased intraoperative blood loss and surgical complexity. Four simple imaging features may serve as reliable indicators of growth direction and help guide preoperative planning.

Ovarian cancer: Novel mechanisms and therapeutic targets regarding the microenvironment in the abdominal cavity

AbstractOvarian cancer is an intractable disease that is mostly diagnosed at an advanced stage and has a high recurrence rate. The early development of characteristic peritoneal dissemination via ascites contributes to a poor prognosis. Based on the “seed and soil” theory, ovarian cancer is considered to form a disseminated tumor that interacts with the peritoneum; superficial mesothelial cells are structurally important. Thus far, we have reported that peritoneal mesothelial cells, which originally are ecological defenses, transform into ovarian cancer‐associated mesothelial cells, which are allies of cancer. They are found to be actively involved in the formation of a friendly “soil” that promotes the survival of “seeds” of ovarian cancer cells. We also demonstrated that the progression of ovarian cancer and the induction of its refractory nature are partially mediated through competition and cooperation between ovarian cancer and mesothelial cells. We believe that it is necessary to shift the aim of treatment strategies from solely targeting cancer cells to focusing on the crosstalk between the surrounding environment and ovarian cancer, an approach that ultimately aims to achieve “coexistence” with cancer through disease control.

Does uterine preservation affect survival outcomes of patients with stage I ovarian sex cord-stromal cell tumours? A multi-institutional study

Sex cord-stromal tumours of the ovary are relatively uncommon neoplasms that account for 3 % of all ovarian cancers. Uterine preservation with careful staging is achievable; however, conservative surgery remains controversial. This study examined the prognostic effects of uterine preservation in patients with stage I sex cord-stromal tumours. This retrospective cohort study was undertaken between January 1986 and February 2019, and the clinicopathological data of 4897 women with malignant ovarian tumours were collected. Seventy-seven patients with stage I sex cord-stromal tumours were eligible for inclusion. The characteristics and survival outcomes of these patients were examined. To investigate the prognostic effects of uterine-preserving surgery, baseline imbalances between patients with and without uterine-preserving surgery were adjusted using an inverse probability of treatment weighting with propensity scores composed of independent clinical variables. The mean ages of patients in the uterine-preserving surgery and non-uterine-preserving surgery groups were 39.8 and 57.8 years, respectively. After inverse probability of treatment weighting adjustments, no significant differences in overall survival (p = 0.205) or recurrence-free survival (p=0.071) were observed between the uterine-preserving surgery and non-uterine-preserving surgery groups. Estimated 10-year overall survival rates were 98.7 % in the uterine-preserving surgery group and 95.9 % in the non-uterine-preserving surgery group, and 10-year recurrence-free survival rates were 87.2 % in the uterine-preserving surgery group and 78.2 % in the non-uterine-preserving surgery group. Uterine-preserving surgery did not significantly affect the site of tumour recurrence. Uterine-preserving surgery may be a feasible surgical option for patients with stage I sex cord-stromal tumours. Further research is needed to guarantee prognostic accuracy and develop effective therapeutic approaches for sex cord-stromal tumours.

Long-term post-recurrence survival outcomes in young women receiving fertility-sparing surgery for epithelial ovarian cancer

The aim of this study was to investigate long-term post-recurrence survival outcomes in young women receiving fertility-sparing surgery (FSS) to verify the feasibility of the limited surgery for epithelial ovarian cancer (OvCa). We performed a regional multicenter retrospective study from January 1986 and March 2020, using clinical data corrected under the central pathological review system. Patients with recurrent tumor after surgery for stage I epithelial OvCa, aged equal or younger than 45 years were included for this study. We evaluated effect of FSS regarding long-term post-recurrence survival with statistical adjustment of propensity score-based method. With the Kaplan-Meier method, original and adjusted survival curves were estimated for recurrence-after survival of patients with (n = 14) and without FSS (n = 26). Median time to disease-specific death was 18.6 months. In both original and adjusted cohorts, there were no significant difference between the two groups (log rank test; P > 0.05). Hazard ratio of disease-specific death was 1.264 (95% confidence interval, 0.563-2.836; P = 0.570) in original and 1.354 (95% confidence interval, 0.702-2.611; P = 0.366) in adjusted population. This result indicated that patients with FSS was not associated with poorer prognosis for recurrence-after survival than those without. When comparing patients not receiving FSS, patients receiving FSS with recurrence at spared ovary followed not significantly different survival outcome as well as those with extra-ovarian recurrence. There was no significant difference of long-term post-recurrence survival outcomes between patients of epithelial OvCa with and without FSS in young women of reproductive age.

Adjuvant taxane plus platinum chemotherapy for stage I ovarian clear cell carcinoma with complete surgical staging: are more than three cycles necessary?

Previous studies on adjuvant chemotherapy for patients with ovarian clear cell carcinoma (OCCC) have included a limited number of Asian patients with surgical stage I OCCC, despite differences in OCCC survival by race and stage. The aim of this study was to estimate the survival effect of the number of cycles of adjuvant taxane plus carboplatin chemotherapy in Asian patients with surgical stage I OCCC. We retrospectively identified 227 patients with surgical stage I OCCC at 14 institutions from 1995 to 2017. Kaplan-Meier analysis and Cox proportional hazard regression with inverse probability of treatment weighting (IPTW) adjustment were performed to evaluate overall survival (OS) and recurrence-free survival (RFS) in patients receiving ≤ 3 and 4-6 cycles of taxane plus platinum adjuvant chemotherapy. Eighty-nine and 138 patients received ≤ 3 and 4-6 cycles of adjuvant chemotherapy, respectively. There was no between-group difference in OS or RFS with or without IPTW adjustment. In Cox proportional hazards analysis, 4-6 cycles of adjuvant chemotherapy were not associated with improved OS (HR 1.090; 95% CI 0.518-2.291; p = 0.821) or RFS (HR 1.144; 95% CI 0.619-2.114; p = 0.669) compared to ≤ 3 cycles, even with IPTW adjustment. Subgroup analysis in different substages of stage I OCCC showed that the number of cycles of adjuvant chemotherapy had no impact on OS or RFS. Three or fewer cycles of taxane plus carboplatin chemotherapy may be a reasonable treatment regime for patients with surgical staging I OCCC.

Pro‐tumoral behavior of omental adipocyte‐derived fibroblasts in tumor microenvironment at the metastatic site of ovarian cancer

AbstractAdipocyte‐rich omentum offers “good soil” for disseminating ovarian cancer (OvCa), contributing to therapeutic difficulty. However, little is understood about the association between adipocytes and tumor growth at peritoneal dissemination site. Herein, we report the induction of adipocyte dedifferentiation by OvCa cells and pro‐tumorigenic effects of resulted adipocyte‐derived fibroblasts. We confirmed that malignant ascites promoted the dedifferentiation of the primary human adipocytes obtained from surgical omental specimen into omental adipocyte‐derived fibroblast (O‐ADF) that possess both mesenchymal stem cell and myofibroblast‐like features. This promotion of dedifferentiation by malignant ascites was blocked by addition of Wnt signaling inhibitor. The effects of dedifferentiated adipocytes in proliferation and migration of OvCa cells were analyzed with in vitro coculturing experimental models and in vivo mice model, and we demonstrated that OvCa cell lines showed enhanced proliferative characteristics, as well as increased migratory abilities upon coculturing with O‐ADF. Additionally, exogenous transforming growth factor‐β1 augmented desmoplastic morphological change of O‐ADF, leading to higher proliferative ability. Our results suggest that OvCa cells promote dedifferentiation of peritoneal adipocytes by activating Wnt/β‐catenin signaling, and generated O‐ADFs exhibit pro‐tumoral hallmarks.

Impact of incomplete surgery and adjuvant chemotherapy for the intraoperative rupture of capsulated stage I epithelial ovarian cancer: a multi-institutional study with an in-depth subgroup analysis

The aim of the present study was to examine the effects of incomplete surgery and adjuvant chemotherapy on the prognosis of patients with intraoperative rupture of capsulated stage I epithelial ovarian cancer (OvCa). A regional retrospective study was conducted between 1986 and 2019. Among 4,730 patients with malignant ovarian tumors, 534 women with International Federation of Gynecology and Obstetrics stage IA and IC1 epithelial OvCa were eligible. Differences in survival outcomes were examined between patients with stage IA and IC1 tumors and the effects of uterine preservation, complete-staging lymphadenectomy, and adjuvant chemotherapy were investigated by an in-depth subgroup analysis. To analyze therapeutic effects, baseline imbalances were adjusted using propensity score (PS). The prognosis of patients with stage IC1 tumors was worse than those with stage IA. Surgical spill did not affect the site of recurrence. In the PS-adjusted subgroup analysis, uterine preservation (hazard ratio [HR]=1.669; 95% confidence interval [CI]=1.052-2.744), incomplete-staging lymphadenectomy (HR=1.689; 95% CI=1.211-2.355), and the omission of adjuvant chemotherapy (HR=3.729; 95% CI=2.090-6.653) significantly increased the HR of recurrence for patients with stage IC1 tumors compared to those with stage IA tumors. Adjuvant chemotherapy decreased the impact of rupture with uterine preservation (HR=0.159; 95% CI=0.230-1.168) or incomplete-staging lymphadenectomy (HR=0.987; 95% CI=0.638-1.527). The present results suggest intraoperative rupture of capsulated stage I epithelial OvCa is associated with a poor prognosis. When chemotherapy is given for patients receiving incomplete surgery, there is no longer an increased risk of recurrence observed with the rupture.

Who are the long-term survivors of recurrent ovarian carcinoma?: a retrospective analysis of a multicenter study

The aim of the present study was to investigate the incidence and hallmarks of long-term survivors of recurrent ovarian carcinoma (LTSROC) in a large-scale retrospective cohort of patients from a multicenter study group. We performed a regional multicenter retrospective study between January 1986 and September 2021 using clinical data collected under the central pathological review system. Patients who underwent surgery for primary OC at diagnosis and developed recurrent tumors after the initial treatment were included. We defined LTSROC as patients who survived for 5 years or longer after initial tumor recurrence and examined factors affecting the long-term survival of ROC and outcomes of LTSROC. We collected information on patients with malignant ovarian tumors and finally 657 of them that developed ROC were included in the study population. Sixty-eight (10.4%) patients were LTSROC while 399 (60.7%) were short-term survivors of recurrent ovarian carcinoma. In a multivariate logistic regression analysis, negative ascites cytology [odds ratio (OR) 1.865; 95% CI 1.026-3.393; p = 0.041] and a recurrence-free interval (RFI) of 1 year or longer (OR 2.896; 95% CI 1.546-5.425; p < 0.001) were identified as independent factors associated with LTSROC. Approximately 80% of LTSROC presented with solitary recurrent tumors. Furthermore, more than 50% of LTSROC underwent tumor debulking surgery for the first recurrent tumor with or without chemotherapy. RFI of 1 year or longer and negative ascites cytology in the initial surgery were identified as independent predictive factors for LTSROC.

Obesity contributes to the stealth peritoneal dissemination of ovarian cancer: a multi‐institutional retrospective cohort study

AbstractObjectiveThe clinical significance of a higher BMI on the prognosis of ovarian cancer remains controversial; therefore, a more detailed analysis is demanded. This study investigated the impact of BMI on peritoneum‐specific recurrence to clarify the involvement of adipose tissue in the proliferation of cancer cells at sites of peritoneal dissemination.MethodsAmong 4,730 patients with malignant ovarian tumors, 280 diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IIIC epithelial ovarian cancer and who underwent complete resection in the primary surgery were included in the present study.ResultsThere were 42, 201, and 37 women in the low, normal, and high BMI groups, respectively. Peritoneum‐specific recurrence‐free survival and overall survival were both significantly shorter in patients with a high BMI than in those with a normal BMI (p = 0.028 and 0.018, respectively). No significant differences were observed in the distribution of sites of recurrence between these two groups. A multivariate analysis identified obesity as an independent prognostic factor in addition to pT3 tumor staging and positive ascites cytology.ConclusionsPatients with a high BMI had a significantly worse prognosis than those with a normal BMI, and peritoneal adipose tissue may have contributed to this difference.

Metastatic Voyage of Ovarian Cancer Cells in Ascites with the Assistance of Various Cellular Components

Epithelial ovarian cancer (EOC) is the most lethal gynecologic malignancy and has a unique metastatic route using ascites, known as the transcoelomic root. However, studies on ascites and contained cellular components have not yet been sufficiently clarified. In this review, we focus on the significance of accumulating ascites, contained EOC cells in the form of spheroids, and interaction with non-malignant host cells. To become resistant against anoikis, EOC cells form spheroids in ascites, where epithelial-to-mesenchymal transition stimulated by transforming growth factor-β can be a key pathway. As spheroids form, EOC cells are also gaining the ability to attach and invade the peritoneum to induce intraperitoneal metastasis, as well as resistance to conventional chemotherapy. Recently, accumulating evidence suggests that EOC spheroids in ascites are composed of not only cancer cells, but also non-malignant cells existing with higher abundance than EOC cells in ascites, including macrophages, mesothelial cells, and lymphocytes. Moreover, hetero-cellular spheroids are demonstrated to form more aggregated spheroids and have higher adhesion ability for the mesothelial layer. To improve the poor prognosis, we need to elucidate the mechanisms of spheroid formation and interactions with non-malignant cells in ascites that are a unique tumor microenvironment for EOC.

Peritoneal restoration by repurposing vitamin D inhibits ovarian cancer dissemination via blockade of the TGF-β1/thrombospondin-1 axis

Ovarian cancer (OvCa), a lethal gynecological malignancy, disseminates to the peritoneum. Mesothelial cells (MCs) act as barriers in the abdominal cavity, preventing the adhesion of cancer cells. However, in patients with OvCa, they are transformed into cancer-associated mesothelial cells (CAMs) via mesenchymal transition and form a favorable microenvironment for tumors to promote metastasis. However, attempts for restoring CAMs to their original state have been limited. Here, we investigated whether inhibition of mesenchymal transition and restoration of MCs by vitamin D suppressed the OvCa dissemination in vitro and in vivo. The effect of vitamin D on the mutual association of MCs and OvCa cells was evaluated using in vitro coculture models and in vivo using a xenograft model. Vitamin D restored the CAMs, and thrombospondin-1 (component of the extracellular matrix that is clinically associated with poor prognosis and is highly expressed in peritoneally metastasized OvCa) was found to promote OvCa cell adhesion and proliferation. Mechanistically, TGF-β1 secreted from OvCa cells enhanced thrombospondin-1 expression in CAMs via Smad-dependent TGF-β signaling. Vitamin D inhibited mesenchymal transition in MCs and suppressed thrombospondin-1 expression via vitamin D receptor/Smad3 competition, contributing to the marked reduction in peritoneal dissemination in vivo. Importantly, vitamin D restored CAMs from a stabilized mesenchymal state to the epithelial state and normalized thrombospondin-1 expression in preclinical models that mimic cancerous peritonitis in vivo. MCs are key players in OvCa dissemination and peritoneal restoration and normalization of thrombospondin-1 expression by vitamin D may be a novel strategy for preventing OvCa dissemination.

Survival benefits of retroperitoneal lymphadenectomy for optimally-resected advanced ovarian high-grade serous carcinoma: a multi-institutional retrospective study

The survival benefits of retroperitoneal lymphadenectomy (RLNA) for epithelial ovarian cancer (EOC) remain controversial because clinical behaviors differ among subtypes. The purpose of the present study was to clarify whether RLNA increases the survival rate of advanced high-grade serous carcinoma (HGSC). This was a retrospective cohort analysis of 3,227 patients with EOC treated between 1986 and 2017 at 14 institutions. Among them, 335 patients with stage IIB-IV HGSC who underwent optimal cytoreduction (residual tumor of <1 cm) were included. Patients were divided into the RLNA group (n=170) and non-RLNA group (n=165). All pathological slides were assessed based on a central pathological review. Oncologic outcomes were compared between the two groups in the original and weighted cohorts adjusted with the inverse probability of treatment weighting. The median observation period was 49.8 (0.5-241.5) months. Overall, 219 (65%) out of 335 patients had recurrence or progression, while 146 (44%) died of the disease. In the original cohort, RLNA was a significant prognostic factor for longer progression-free survival (PFS) (hazard ratio [HR]=0.741; 95% confidence interval [CI]=0.558-0.985) and overall survival (OS) (HR=0.652; 95% CI=0.459-0.927). In the weighted cohort in which all variables were well balanced as standardized differences decreased, RLNA was also a significant prognostic factor for more favorable oncologic outcomes (PFS, adjusted HR=0.742; 95% CI=0.613-0.899) and OS, adjusted HR=0.620; 95% CI=0.488-0.787). The present study demonstrated that RLNA for stage III-IV HGSC with no residual tumor after primary debulking surgery contributed to better oncologic outcomes.

Follicular dendritic cell sarcoma of the uterine cervix: a case report

Abstract Background Follicular dendritic cell sarcoma (FDCS) is a rare mesenchymal tumor that mostly occurs in systemic lymph nodes. FDCS in the uterine cervix has not yet been reported. Case presentation A 49-year-old woman was referred to our department with a cervical tumor, which was histologically suspected to be undifferentiated carcinoma. She underwent hysterectomy, salpingo-oophorectomy, and pelvic lymphadenectomy after neoadjuvant chemotherapy with paclitaxel and carboplatin. The resected specimen contained high numbers of spindle cells and was immunohistochemically confirmed to be FDCS. The tumor was completely resected and recurrence was not detected at a 16-month follow-up. Conclusion FDCS is an extremely rare malignant tumor in the uterine cervix, and an accurate diagnosis and complete resection are essential for a good prognosis.

An update of oncologic and obstetric outcomes of radical trachelectomy for early‐stage cervical cancer: The need for further minimally invasive treatment

AbstractAimsTo investigate the oncologic and obstetric outcomes of radical trachelectomy (RT) in patients with early‐stage cervical cancer and to evaluate the potential role of fertility‐preserving treatments in improving pregnancy outcomes while oncologic status is stable.MethodsIn this single‐institution study, we analyzed the oncologic and obstetric outcomes of 67 patients with early‐stage cervical cancer who underwent RT at Nagoya University Hospital.ResultsThe cancer recurrence rate (6.0%) and the mortality rate (1.5%) were comparable with those of previous studies. Of the 46 patients who attempted to conceive after RT, 19 (41.3%) became pregnant, and 16 gave birth. Of these 37.5% delivered at term, and delivery at less than 28 weeks of gestation occurred in 31.3% of pregnancies.ConclusionsRT is a viable treatment option for selected patients with early‐stage cervical cancer. However, the use of less invasive techniques, such as conization/simple trachelectomy and pelvic lymph node dissection, may improve pregnancy outcomes while oncologic status is stable.