Published papers

Aim: To provide information including the trend of gynecological malignancies in Japan, we hereby present the Annual Patient Report for 2017 and the Annual Treatment Report for 2012, on the outcomes of patients who started treatment in 2012. Methods: The Japan Society of Obstetrics and Gynecology maintains an annual tumor registry, where information on gynecological malignancies from various participating institutions is gathered. The data of patients whose treatment with gynecologic malignancies was initiated in 2017 were analyzed retrospectively. Survival of the patients who started treatment with cervical, endometrial and ovarian cancer in 2012 was analyzed by using the Kaplan-Meier, log-rank and Wilcoxon tests. Results: Treatment was initiated in 2017 for 7710 patients with cervical cancer; 11 120 with endometrial cancer; 7029 with ovarian, tubal and peritoneal cancer; 2164 with ovarian borderline tumors; and with the others (213 vulvar cancer, 139 vaginal cancer, 366 uterine sarcoma, 41 uterine adenosarcoma and 131 trophoblastic diseases). This clinicopathological information was summarized as the patient annual report. The 5-year survival rates of the patients with cervical cancer were 92.9, 75.5, 58.2 and 26.7% for stages I, II, III and IV, respectively. The 5-year survival rates for the patients with endometrial cancer were 93.6, 85.6, 72.6 and 27.3% for stages I, II, III and IV, respectively. The 5-year survival rates for the patients with ovarian cancer (surface epithelial-stromal tumors) were 92.5, 83.5, 49.5 and 30.8% for stages I, II, III and IV, respectively. Conclusion: The annual tumor report is an important survey that provides knowledge on gynecological malignancy trends in Japan.

© 2020 The Author(s). Background: The number of cases of novel coronavirus disease 2019 (COVID-19) in Japan have risen since the first case was reported on January 24, 2020, and 6225 infections have been reported as of June 30, 2020. On April 8, 2020, our hospital began screening patients via pre-admission reverse transcriptase-polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and chest computed tomography (CT). Although no patients exhibited apparent pneumonia, treatment delay or changes in treatment plans were required for a few patients based on the results of screening tests. During an emerging infectious disease pandemic, the likelihood of being infected, as well as the disease itself, affects clinical decision making in several ways. We summarized and presented our experience. Case presentation: After the introduction of pre-admission screening, RT-PCR and CT were performed in 200 and 76 patients, respectively, as of June 30, 2020. The treatment of five patients, including two patients with cervical cancer, two patients with ovarian tumors, and one patient with ovarian cancer, was affected by the results. Two asymptomatic RT-PCR-positive patients did not develop COVID-19, but their treatment was delayed until the confirmation of negative results. The other three patients were RT-PCR-negative, but abnormal CT findings suggested the possibility of COVID-19, which delayed treatment. The patients receiving first-line preoperative chemotherapy for ovarian cancer had clinically evident exacerbations because of the treatment delay. Conclusion: During the epidemic phase of an emerging infectious disease, we found that COVID-19 has several other effects besides its incidence. The postponing treatment was the most common, therefore, treatment of ovarian tumors and ovarian cancer was considered to be the most likely to be affected among gynecological diseases. Protocols that allow for easy over-diagnosis can be disadvantageous, mainly because of treatment delays, and therefore, the protocols must be developed in light of the local infection situation.

Objective: The purpose of our study was to conduct a detailed survey of radical hysterectomy in Japanese patients with early-stage cervical cancer, and to compare oncologic outcomes between open and minimally invasive radical hysterectomy. Methods: In Japan during 2015, the medical records of 929 patients with FIGO stage IB1 and IIA disease treated with radical hysterectomy were retrospectively reviewed. We assessed patients’ characteristics, disease-free survival (DFS), overall survival (OS) and prognostic factors for survival. Results: The median patient age was 44 (20–80) years. Most patients (94.4%) had stage IB1 disease. Of the patients who underwent radical hysterectomy, 91.2% underwent open surgery and 8.8% underwent minimally invasive surgery (MIS). The median follow-up period was 40.8 months (range, 0.49–51.1 months). The rate of DFS and OS at 4 years in all patients was 88.3% and 96.4%, respectively. Multivariate analysis identified age (≥ 47), adenocarcinoma histology, tumor size (≥ 2 cm), parametrial invasion, positive lymph node metastasis and institutional accreditation as independent predictors of recurrence, and adenocarcinoma, other cell types, and positive lymph node metastasis as independent predictors of death. Oncologic outcomes in all patients were similar between open and MIS, including DFS and OS. Conclusion: The survival rate of the Japanese patients underwent radical hysterectomy for early-stage cervical cancer was favorable. No significant differences were observed for DFS and OS between open and MIS performed by a limited number of surgeons at a limited number of facilities in Japan. Further investigations are required to identify the appropriate patients might benefit from MIS.

背景:若年の子宮体癌,子宮内膜異型増殖症(AEH)に対する妊孕性温存療法として,medroxyprogesterone acetate(MPA)を用いた高用量黄体ホルモン療法があるがその再発率の高さが問題となる.本研究ではMPA療法後の再発例の特徴を明らかにすることを目的とした.方法:1998〜2015年,当科で初回治療としてMPA療法を施行した182名を対象とし,倫理委員会の承認のもと,臨床病理学的因子や予後について後方視的に解析した.初回治療前の組織型はAEHで再発時AEHであった34例をA群,初回治療時EMG1で再発時AEHであった37例をB群,初回治療時EMG1で再発時EMG1であった27例をC群とした.結果:病変消失率はいずれも100%で,A群はB+C群に比較し再々発率が低く,再々発までの期間が長かった.妊娠例と非妊娠例では再々発率,再々発までの期間に有意差を認めなかった.結論:G1症例では再発時に進行する可能性もあり慎重な管理が求められる.治療後妊娠例は再発が少ないことから病変消失後の積極的な不妊治療がすすめられるが,分娩後も再発する可能性があり継続した管理が求められる.(著者抄録)

© 2019 Elsevier Inc. Objective: To examine the trends of epithelial ovarian cancer histologic subtypes in Japan. Methods: A nationwide retrospective registry study was performed between 2002 and 2015 (Japan cohort, n = 48,640). Trends were also examined in The Surveillance, Epidemiology, and End Results Program (US cohort, n = 49,936). Time-specific proportional changes of four major histological subtypes (serous, clear cell, endometrioid, and mucinous) were examined. Results: The Japan cohort had more stage I disease (44.1% versus 24.9%) and less stage IV disease (10.0% versus 23.1%) than the US cohort (P < 0.001). The Japan cohort had more non-serous histology, particularly clear cell carcinoma (26.9% versus 8.4%), than the US cohort (P < 0.001). In the Japan cohort, proportion of clear cell carcinoma increased significantly from 23.4% to 29.1% between 2002 and 2010 (P < 0.001). Among stage I disease, clear cell carcinoma increased significantly in the Japan cohort from 32.9% to 40.3% between 2002 and 2015 (P < 0.001), whereas mucinous carcinoma increased significantly in the US cohort from 15.0% to 24.8% (P = 0.01). In 2015, clear cell carcinoma was most common among women aged <50 years from the Japan cohort (30.2%) versus serous carcinoma in the US cohort (50.8%). In the Japan cohort, the peak age was 75 years for serous, 57 for clear cell, and 45 for endometrioid carcinoma (P < 0.001). Mucinous carcinoma decreased until 43 years and increased again after age 73 years (P < 0.001). Conclusion: Characteristics of epithelial ovarian cancer in Japan are largely different compared to the US. In Japan, clear cell carcinoma has increased significantly in recent years to account for nearly 30% of epithelial ovarian cancer.

© 2019 by the American College of Obstetricians and Gynecologists. Published by Wolters Kluwer Health, Inc. OBJECTIVE:To examine the incidence and prognostic effects of intraoperative capsule rupture and to assess the effectiveness of postoperative chemotherapy for intraoperative tumor rupture in apparent stage I epithelial ovarian cancer.METHODS:This is a society-based retrospective observational study in Japan that examined 15,163 women with stage IA-IC1 epithelial ovarian cancer who underwent primary surgical treatment between 2002 and 2015. Associations between intraoperative capsule rupture and cause-specific survival, and between postoperative chemotherapy and cause-specific survival among intraoperatively ruptured cases were examined by histology type (clear cell n=6,107, endometrioid n=3,910, mucinous n=3,382, and serous n=1,764).RESULTS:Clear cell histology had the highest risk of intraoperative capsule rupture (57.3%), followed by endometrioid (48.8%), serous (41.8%), and mucinous (32.0%) histologies (P<.001). On multivariable analysis, clear cell type exhibited the largest effect of intraoperative capsule rupture on cause-specific survival (adjusted hazard ratio [HR] 1.99, 95% CI 1.45-2.75), followed by serous (adjusted HR, 1.61, 95% CI 0.84-3.11), mucinous (adjusted HR 1.28, 95% CI 0.79-2.09), and endometrioid (adjusted HR, 1.14, 95% CI 0.64-2.01) tumors. Postoperative chemotherapy for intraoperatively ruptured cases did not improve cause-specific survival in any histologic types in multivariable analysis: clear cell, adjusted HR 0.86, 95% CI 0.56-1.31; serous, adjusted HR 1.08, 95% CI 0.42-2.74; mucinous, adjusted HR 1.11, 95% CI 0.55-2.27; and endometrioid, adjusted HR 2.81, 95% CI 0.85-9.30 (all, P>.05). In the cohort-level analysis of ruptured cases (n=7,227), postoperative chemotherapy use has significantly decreased in mucinous (16.3% relative decrease), endometrioid (13.1% relative decrease), and clear cell (9.3% relative decrease) (all, P<.05); but, the cohort-level 5-year cause-specific survival rate did not change over time (all, P>.05).CONCLUSION:Among apparent stage I epithelial ovarian cancer, the clear cell type possesses a disproportionally high risk of capsule rupture during adnexectomy and is associated with the most adverse effect on survival. A decrease in the use of postoperative chemotherapy for intraoperatively ruptured cases in Japan is likely the result of increasing awareness of the absence of survival benefits.

© 2019 The Author(s) 2019. Published by Oxford University Press. The present study was performed to clarify the significance of DNA methylation alterations during endometrial carcinogenesis. Genome-wide DNA methylation analysis and targeted sequencing of tumor-related genes were performed using the Infinium MethylationEPIC BeadChip and the Ion AmpliSeq Cancer Hotspot Panel v2, respectively, for 31 samples of normal control endometrial tissue from patients without endometrial cancer and 81 samples of endometrial cancer tissue. Principal component analysis revealed that tumor samples had a DNA methylation profile distinct from that of control samples. Gene Ontology enrichment analysis revealed significant differences of DNA methylation at 1034 CpG sites between early-onset endometrioid endometrial cancer (EE) tissue (patients aged ≤40 years) and late-onset endometrioid endometrial cancer (LE) tissue, which were accumulated among 'transcriptional factors'. Mutations of the CTNNB1 gene or DNA methylation alterations of genes participating in Wnt signaling were frequent in EEs, whereas genetic and epigenetic alterations of fibroblast growth factor signaling genes were observed in LEs. Unsupervised hierarchical clustering grouped EE samples in Cluster EA (n = 22) and samples in Cluster EB (n = 12). Clinicopathologically less aggressive tumors tended to be accumulated in Cluster EB, and DNA methylation levels of 18 genes including HOXA9, HOXD10 and SOX11 were associated with differences in such aggressiveness between the two clusters. We identified 11 marker CpG sites that discriminated EB samples from EA samples with 100% sensitivity and specificity. These data indicate that genetically and epigenetically different pathways may participate in the development of EEs and LEs, and that DNA methylation profiling may help predict tumors that are less aggressive and amenable to fertility preservation treatment.

Copyright © 2020. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology. OBJECTIVE: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. (1) Background: This study examined the use of a two-tier system in grouping cervical adenocarcinoma for survival discrimination. (2) Methods: A nationwide retrospective observational cohort study was conducted using the Japan Society of Gynecologic Oncology tumor registry database from 2001 to 2015 (n = 86,754). Adenocarcinoma subtypes were grouped as type 1 (endocervical usual type and endometrioid) or type 2 (serous, clear, mucinous, and not otherwise specified), based on their relative survival compared with that of squamous tumors. (3) Results: The majority of the adenocarcinoma cases were type 1 (n = 10,121) versus type 2 tumors (n = 5157). Type 2 tumors were more likely to be old and have stage IV disease than those with squamous tumors. The number of type 2 tumors increased from 2001 to 2014 (106.1% relative increase, p < 0.001). Type 2 tumors had disproportionally poorer survival compared to other types (5-year survival rates: 68.9% for type 2, 75.4% for type 1, and 78.0% for squamous; p < 0.001). On multivariate analysis, type 2 tumors remained an independent prognostic factor associated with decreased survival compared with squamous (adjusted hazard ratio 2.00, 95% CI 1.84–2.15, p < 0.001). (4) Conclusion: The survival of cervical adenocarcinoma varies largely across the histological subtypes, and the proposed two-tier grouping may be useful for survival discrimination.

© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com. BACKGROUND: To 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. METHODS: A 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. RESULTS: A 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. CONCLUSIONS: Outpatient 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.

© 2020 Elsevier Inc. Objective: The Japan Society of Gynecologic Oncology published its first clinical guidelines for uterine cervical cancer in 2007 which has been revised twice in 2011 and 2017. The aim of this study was to investigate the influence of the first guideline publication on the therapeutic trend and patient outcome by analyzing uterine cervical cancer cases registered to the cancer registry organized by the Japan Society of Obstetrics and Gynecology. Methods: Data of uterine cervical cancer cases registered to the cancer registry from 2000 to 2012 were provided. Epidemiological and clinical trend were analyzed by the Chi-squared test with subsequent standardized residual analysis. Overall survival among the patients registered between 2004 and 2009 was analyzed using the Fine and Gray competing risk model. Results: 68,707 cases were registered during the study period. A trend analysis revealed that the guideline publication may have led to a decrease in neoadjuvant chemotherapy in parallel with an increase in radiation therapy mainly in stage II and III patients undergoing primary treatment. A survival analysis indicated that the introduction of the guideline may have improved overall survival among stage III uterine cervical cancer patients, even though a significant difference was not observed in all of the cases. Conclusions: This study demonstrated the potential influence of the guideline publication on the clinical trend and patient outcome. As this is the first assessment of the guideline for uterine cervical cancer in Japan, continuous evaluation is necessary to further comprehend the significance of this guideline.

© 2020 The Authors. Cancer Medicine published by John Wiley & Sons Ltd. Precision medicine based on cancer genomics is being applied in clinical practice. However, patients do not always derive benefits from genomic testing. Here, we performed targeted amplicon exome sequencing-based panel tests, including 160 cancer-related genes (PleSSision-160), on 88 malignant ovarian tumors (high-grade serous carcinoma, 27; endometrioid carcinoma, 15; clear cell carcinoma, 30; mucinous carcinoma, 6; undifferentiated carcinoma, 4; and others, 6 (immature teratoma, 1; carcinosarcoma, 3; squamous cell carcinoma, 1; and mixed, 1)), to assess treatment strategies and useful biomarkers for malignant ovarian tumors. Overall, actionable gene variants were found in 90.9%, and druggable gene variants were found in 40.9% of the cases. Actionable BRCA1 and BRCA2 variants were found in 4.5% of each of the cases. ERBB2 amplification was found in 33.3% of mucinous carcinoma cases. Druggable hypermutation/ultramutation (tumor mutation burden ≥ 10 SNVs/Mbp) was found in 7.4% of high-grade serous carcinoma, 46.7% of endometrioid carcinoma, 10% of clear cell carcinoma, 0% of mucinous carcinoma, 25% of undifferentiated carcinoma, and 33.3% of the other cancer cases. Copy number alterations were significantly higher in high-grade serous carcinoma (P <.005) than in other histologic subtypes; some clear cell carcinoma showed high copy number alterations that were correlated with advanced stage (P <.05) and worse survival (P <.01). A high count of copy number alteration was associated with worse survival in all malignant ovarian tumors (P <.05). Our study shows that targeted agents can be detected in approximately 40% of malignant ovarian tumors via multigene panel testing, and copy number alteration count can be a useful marker to help assess risks in malignant ovarian tumor patients.

© 2020, The Author(s). The use of primary patient-derived organoids for drug sensitivity and resistance testing could play an important role in precision cancer medicine. We developed expandable ovarian cancer organoids in < 3 weeks; these organoids captured the characteristics of histological cancer subtypes and replicated the mutational landscape of the primary tumours. Seven pairs of organoids (3 high-grade serous, 1 clear cell, 3 endometrioid) and original tumours shared 59.5% (36.1–73.1%) of the variants identified. Copy number variations were also similar among organoids and primary tumours. The organoid that harboured the BRCA1 pathogenic variant (p.L63*) showed a higher sensitivity to PARP inhibitor, olaparib, as well as to platinum drugs compared to the other organoids, whereas an organoid derived from clear cell ovarian cancer was resistant to conventional drugs for ovarian cancer, namely platinum drugs, paclitaxel, and olaparib. The overall success rate of primary organoid culture, including those of various histological subtypes, was 80% (28/35). Our data show that patient-derived organoids are suitable physiological ex vivo cancer models that can be used to screen effective personalised ovarian cancer drugs.