Published papers

PURPOSELenvatinib plus pembrolizumab (len + pembro) significantly improved progression-free survival (PFS) and overall survival (OS) versus chemotherapy in previously treated advanced or recurrent endometrial cancer (aEC) in the phase III Study 309/KEYNOTE-775. We report results from the phase III, randomized, open-label European Network of Gynaecological Oncological Trial-en9/LEAP-001 study (ClinicalTrials.gov identifier: NCT03884101) that evaluated len + pembro versus chemotherapy in first-line aEC.METHODSPatients with stage III to IV or recurrent, radiographically apparent EC and no previous chemotherapy or disease progression ≥6 months after neo/adjuvant platinum-based chemotherapy were randomly assigned 1:1 to lenvatinib 20 mg once daily plus pembrolizumab 200 mg once every 3 weeks or paclitaxel 175 mg/m2 plus carboplatin AUC 6 mg/mL/min once every 3 weeks. Primary end points were PFS and OS, evaluated in the mismatch repair-proficient (pMMR) and all-comers populations. Noninferiority was assessed for OS at final analysis (FA) for len + pembro versus chemotherapy (multiplicity-adjusted, one-sided nominal alpha,.0159; null hypothesis-tested hazard ratio [HR], 1.1).RESULTSEight hundred forty-two patients were randomly assigned (len + pembro, n = 420 [pMMR population, n = 320]; chemotherapy, n = 422 [pMMR population, n = 322]). At FA (data cutoff, October 2, 2023), median PFS (95% CI) in the pMMR population was 9.6 (8.2 to 11.9) versus 10.2 (8.4 to 10.5) months with len + pembro versus chemotherapy (hazard ratio [HR], 0.99 [95% CI, 0.82 to 1.21]) and among all-comers was 12.5 (10.3 to 15.1) versus 10.2 (8.4 to 10.4) months (HR, 0.91 [95% CI, 0.76 to 1.09]; descriptive analyses). Median OS (95% CI) in the pMMR population was 30.9 (25.4 to 37.7) versus 29.4 (26.2 to 35.4) months with len + pembro versus chemotherapy (HR, 1.02 [95% CI, 0.83 to 1.26]; noninferiority P =.246, not statistically significant per multiplicity control strategy) and among all-comers was 37.7 (32.2 to 43.6) versus 32.1 (27.2 to 35.7) months (HR, 0.93 [95% CI, 0.77 to 1.12]). Grade ≥3 treatment-related adverse events occurred in 331/420 (79%) versus 274/411 (67%) treated patients.CONCLUSIONFirst-line len + pembro did not meet prespecified statistical criteria for PFS or OS versus chemotherapy in pMMR aEC.

Aim: To provide information including the trend of gynecological malignancies in Japan, we hereby present the Annual Patient Report for 2022 and the Annual Treatment Report for 2017, on the outcomes of patients who started treatment in 2017. 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 2022 were analyzed retrospectively. Survival of the patients who started treatment with cervical, endometrial, and ovarian cancer in 2017 was analyzed by using the Kaplan–Meier, log–rank, and Wilcoxson tests. Results: Treatment was initiated in 2022 for 8039 patients with cervical cancer, 14 518 with endometrial cancer, 8524 with ovarian, tubal, and peritoneal cancer, 2360 with ovarian borderline tumors, and with the others (270 vulvar cancer, 179 vaginal cancer, 539 uterine sarcoma, 48 uterine adenosarcoma, 158 trophoblastic diseases). This clinicopathological information was summarized as the Patient Annual Report. The 5-year survival rates of the patients who initiated treatment in 2017 were as follows. For cervical cancer, the rates were 93.0%, 76.1%, 59.5%, and 28.3% for Stages I, II, III, and IV, respectively. For endometrial cancer, the rates were 94.9%, 88.8%, 72.7%, and 28.9% for Stages I, II, III, and IV, respectively. For ovarian cancer, the rates were 91.7%, 76.6%, 54.4%, and 45.2% 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.

Objective: To evaluate the survival impact of neoadjuvant chemotherapy followed by interval debulking surgery (NACT/IDS) versus primary debulking surgery (PDS) in patients with advanced epithelial ovarian cancer of non–high-grade serous carcinoma (HGSC) histology. Methods: A retrospective analysis was conducted using the Japan Society of Obstetrics and Gynecology tumor registry (2017 to 2022). Patients with FIGO stage III–IV ovarian, fallopian tube, or primary peritoneal cancer were classified by histology (HGSC or non-HGSC), and compared initial treatment. Overall survival (OS) was analyzed using multivariate Cox proportional hazard model and propensity score matching (PSM). Results: Among 20,212 eligible cases, 14,718 (72.8 %) were HGSC and 5494 (27.2 %) were non-HGSC, primarily clear cell (2389;11.8 %) and endometrioid (1431;7.1 %) carcinomas. In HGSC patients, 7118 (48.4 %) received NACT, while in non-HGSC, 1203 (21.9 %) received NACT. Compared with HGSC, non-HGSC patients were younger, more frequently registered in eastern Japan, diagnosed at FIGO 2014 stage IIIA/IIIB, and underwent PDS and nodal evaluation (all, P < .05). In the overall cohort, non-HGSC histology was independently associated with poorer OS (adjusted-hazard ratio [HR]1.35, P < .001). Upstaging/IDS failure was higher in non-HGSC (36 %) vs HGSC (25 %, P < .001). After PSM, 5-year OS was comparable between HGSC patients who achieved IDS after NACT and those who underwent PDS (36.8 % vs 35.6 %; HR0.83, P = .12), whereas IDS failure was associated with markedly worse survival (3.9 %; HR3.12, P < .001). Conclusion: In non-HGSC, the rate of upstaging/IDS failure after NACT reached approximately 36 %; however, achieving IDS after NACT resulted in survival comparable to PDS, highlighting the need to select appropriate candidates.

Brain metastasis from ovarian cancer is a very rare condition with a poor prognosis. However, due to its rarity, there is no established treatment strategy. We present a case series of brain metastasis with ovarian cancer, focusing on two long-term survivors treated with multimodal therapy. Among the nine cases, the median survival time after brain metastases was six months (range: 0–58 months). Eight patients had high-grade serous carcinoma (HGSC). Three of the four patients who underwent genetic testing tested positive for germline BRCA2 (gBRCA2) mutation. Two patients survived longer than 4 years after the diagnosis of brain metastases. Both of these patients received chemotherapy, radiation therapy, and olaparib, a molecularly targeted drug, as maintenance therapy. This case series suggests that patients with gBRCA2 mutation-positive HGSC may be at a high risk of developing brain metastases. A multidisciplinary approach, including PARP inhibitors, may improve the prognosis of patients with brain metastases from ovarian cancer.

Objective: The aim of this study was to review the clinicopathological characteristics of small cell neuroendocrine cervical cancer (SCNEC) and to identify the optimal treatment. Methods: The Japanese Society of Gynecologic Oncology conducted a retrospective cohort study of SCNECs enrolled in the Gynecological Tumor Registry of the Japan Society of Obstetrics and Gynecology between 2004 and 2015. All cases were modified and unified by International Federation of Gynecology and Obstetrics 2008 (Union for International Cancer Control 7th edition). Results: There were 822 registered patients diagnosed with SCNEC from 2004 to 2015 which comprised 1.1% (822/73,698) of all uterine cervical cancer cases. Rates of lymph-node and distant metastasis were significantly higher in T1b2 (38.9% and 13.7%, respectively) than T1b1 (14.2% and 4.4%, respectively) (p<0.01). In IB2 and T1bN1M0 SCNEC, the 5-year survival rate with surgery followed by chemotherapy was significantly higher than that with surgery followed by radiation therapy/concurrent chemoradiation therapy (p<0.01). Conclusion: SNCEC tumors >4 cm in size had greater rates of lymph-node and distant metastasis when compared with tumors ≤4 cm. Adjuvant chemotherapy, rather than radiotherapy, may improve prognosis after surgery in T1bN1M0 SCNEC.

Objective Regional lymph node (LN) dissection is a standard surgical procedure for endometrial cancer, but there is currently no clear consensus on its therapeutic significance. We aimed to determine the impact of regional LN dissection on the outcome of endometrial cancer. Methods Study subjects comprised 36,813 patients who were registered in the gynecological tumor registry of the Japan Society of Obstetrics and Gynecology, had undergone initial surgery for endometrial cancer between 2004 and 2011, and whose clinicopathological factors and prognosis were appropriate for our investigation. The following clinicopathological factors were obtained from the registry: age, surgical stage classification, Union for International Cancer Control tumor, node, metastasis classification, histological type, histological differentiation, presence or absence of LN dissection, and postoperative treatment. We retrospectively analyzed the clinicopathological factors and therapeutic outcomes for patients with endometrial cancer. Results Analysis of all subjects showed that the group that underwent LN dissection had a significantly better overall survival than the group that did not undergo dissection. Analysis based on stage showed similar results across groups, except for stage Ia. Analysis based on stage and histological type showed similar results across groups, except for stage Ia endometrial carcinoma G1 or Ia G2. Multivariate analysis of prognostic factors indicated that LN dissection is an independent prognostic factor and that it has a greater impact on prognosis than adjuvant chemotherapy. Conclusion Despite the limitations of a retrospective study with some biases, the results suggest that LN dissection in endometrial cancer has a prognostic effect.

Background: Sentinel lymph node (SN) biopsy is essential for evaluating survival and minimal treatment-related morbidity associated with cervical, endometrial, and vulvar cancer in Japan. As such, our aim in this study was to evaluate the current practice pattern of using SN biopsy for cervical, endometrial, and vulvar cancer in Japan. Methods: We deployed a 47-question survey on the use of SN biopsy for gynecological cancers to 216 gynecological oncology training facilities. The survey included information on the use of SN biopsy for uterine (cervical and endometrial) and vulvar cancers; details on the type, timing, and concentration of tracers used; surgical approach used for SN biopsy; method of biopsy and pathological examination; and facilities’ experience with clinical research on SN biopsy. Results: The response rate was 84% (181/216), with 40 facilities (22%) having experience in SN biopsy for gynecological cancers, 34 (85%) for uterine cancers, and 15 (37%) for vulvar cancers. Radioisotope, indocyanine green (ICG), and blue dyes were available for the detection of uterine cancers in 21 (52%), 25 (62%), and 19 (48%) facilities and for vulvar cancers in 9 (22%), 3 (7%), and 11 (27%) facilities, respectively. Thirty-four facilities (85%) used intraoperative frozen section procedure for diagnosis when possible, with 24 (71%) of these facilities using 2-mm specimen cuts. Diagnosis included pathological examination (85%), immunostaining (57%), and one-step nucleic acid amplification (5%). Conclusion: Increasing research evidence, providing insurance coverage for radioisotope tracers, and increasing the availability of training are expected to increase the use of SN biopsy in Japan.

[Objective] Lynch syndrome (LS) is an autosomal dominant inherited disorder caused by a germline pathogenic variant in DNA mismatch repair (MMR) genes. Endometrial cancer frequently precedes another LS-associated tumor. This study aimed to clarify the incidence and features of LS in young Japanese endometrial cancer patients. [Methods] Sixty-five patients aged 40 years or younger, who were diagnosed with endometrial cancer, were enrolled in this study. Targeted sequencing of a hereditary colorectal cancer-related gene panel including the MMR genes MLH1, MSH2, MSH6, and PMS2 was conducted on DNA samples extracted from blood cells. [Results] Overall, 6 missense variants (2 in MSH2, 2 in MSH6, and 2 in PMS2), 1 inframe deletion variant in MSH2, 1 splice variant in MSH2, and 1 two-base substitution in the 3’ untranslated region in MLH1 were detected in 9 (13.8%) patients. Among these, the splice variant c.1276G > T (p.Ile411_Gly426del16) in MSH2 was annotated as pathogenic, while other variants were of uncertain significance. The patient with the pathogenic variant had a family history of endometrial and colorectal cancer and was diagnosed with endometrial cancer at age 35. [Conclusion] The incidence of LS among Japanese endometrial cancer patients of reproductive age (≤ 40 years) in this study was at least 1.5%; however, 12.3% of patients had variants of uncertain significance in MMR genes.

Objective: 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. Methods: 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. Results: 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). Conclusions: 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.

Objective: To evaluate the accuracy of preoperative endometrial biopsy and magnetic resonance imaging (MRI) of endometrial cancer compared with that of intraoperative frozen section. Methods: This retrospective study included 264 patients who underwent surgery with intraoperative frozen section for endometrial cancer at our institution between 2014 and 2018. Diagnosis was determined by histologic type, grade, and myometrial invasion. Concordance rate, sensitivity, and specificity of preoperative diagnosis and intraoperative frozen diagnosis were calculated, in comparison to the final pathologic diagnosis. Results: Preoperative and intraoperative diagnoses showed no statistically significant difference in determining histologic type and grade (P = 0.152). Intraoperative diagnosis showed higher sensitivity for endometrioid carcinoma grade 3 and other types, and higher specificity for grade 1. For myometrial invasion, intraoperative diagnosis showed significantly higher concordance rate than preoperative MRI findings (P < 0.01). Intraoperative diagnosis showed higher sensitivity and specificity in patients with and without myometrial invasion, respectively. Conclusion: Higher agreement between intraoperative and final diagnoses, especially in myometrial invasion, suggests that intraoperative frozen section is a good indicator for appropriate surgical procedure decision making.

Aim: This study aimed to clarify the impact of coronavirus disease 2019 on gynecology practice in Japan, in particular, on surgeries for benign gynecological diseases. Methods: An online questionnaire was distributed to 966 facilities in Japan, including core facilities, facilities participating in perinatal and gynecologic oncology registries, and facilities certified for training by the Japanese Society of Obstetrics and Gynecology Endoscopy. The number of surgeries performed was compared between 2019 and 2020, when the novel coronavirus disease was prevalent. Results: Five hundred and eighty (58.2%) facilities responded. The total number of surgeries decreased from 129 648 in 2019 to 118 565 in 2020, by 8.5%, for all surgical procedures. However, there was a clear increase in the number of robotic surgeries performed in 2020 compared to that in 2019 for all populations. The number of total hysterectomies decreased markedly from 15 385 in 2019 to 12 531 in 2020, a fall of 10.1%. Conclusions: The number of surgeries for benign gynecological diseases decreased by 8.5% in 2020 compared to that in 2019. This value is among the lowest in the world.

Background: To investigate perinatal outcomes in pregnancy after high-dose medroxyprogesterone acetate (MPA) therapy for early stage endometrial cancer (EC) and atypical endometrial hyperplasia (AEH) and to determine whether pregnancy after MPA therapy is at a higher risk of placenta accreta. Methods: Data of 51 pregnancies in 46 women who received MPA therapy for EC or AEH and delivered after 22 weeks of gestation at Keio University Hospital were reviewed. A retrospective matched case–control study was performed to determine the risk of placenta accreta in pregnancy after MPA therapy compared with singleton pregnancies without any history of maternal malignancy treatments. Results: The incidence of placenta accreta was higher in the MPA group than in the control group (15.7 vs. 0%, p = 0.0058). However, no differences in other perinatal outcomes were observed between groups. While gestational weeks at delivery in the MPA group were later than those in the control group (p = 0.0058), no difference in the incidence of preterm delivery was recorded between groups. In the MPA therapy group, the number of patients who underwent ≥ 6 dilation and curettage (D&C) was higher in the placenta accreta group than in the non-placenta accreta group (50.0 vs. 14.0%, p = 0.018). Patients with ≥ 6 D&Cs demonstrated a 6.0-fold increased risk of placenta accreta (p = 0.043, 95% CI 1.05–34.1) than those receiving ≤ 3 D&Cs. Conclusion: Pregnancy after MPA therapy is associated with a high risk of placenta accreta. In cases in which the frequency of D&C is high, placenta accreta should be considered.

Background: The influence of the coronavirus disease 2019 (COVID-19) pandemic on the number of newly diagnosed gynecological cancers has not been extensively investigated in Japan. This study determined the impact of COVID-19 on the incidence of gynecological cancer. Methods: Using the Japanese Society of Obstetricians and Gynecologic Oncology registry database, the distribution of the number of patients based on clinical staging or tumor-node-metastasis classifications before and during the COVID-19 pandemic was analyzed to compare the trends. The clinical staging classification of cervical cancer in Japan was based on the International Federation of Gynecology and Obstetrics (FIGO) 2008 from 2018 to 2020 and on the FIGO 2018 from 2021. Since FIGO-2018 classified N1 cases as stage IIIC, we focused on T classification without referencing the clinical staging (FIGO staging) of patients with cervical cancer in 2021. Results: The number of patients with endometrial cancer and malignant ovarian tumors of all clinical stages increased uniformly yearly, while that of those with stage III cervical cancer rapidly increased in 2021 owing to the adoption of the revised classification. On comparing cases of cervical cancer in 2020 and 2021, we found that T1 cases decreased and T2 and T3 cases increased in 2021 compared to those in 2020 (p = 0.006). Cervical intraepithelial neoplasia/adenocarcinoma in situ incidence decreased in 2020 compared to that in 2019 but increased again in 2021. The number of patients with cervical cancer decreased in most prefectures in 2020. Conclusion: The incidence of locally advanced cervical cancer increased during the COVID-19 pandemic.

The concept of gastric-type mucinous carcinoma of the uterine cervix (GAS) has been accepted worldwide because of its aggressive clinical behaviour and the absence of high-risk human papilloma virus infection. The World Health Organization (WHO) 2020 classification divides cervical tumours into two categories: human papilloma virus-associated and human papilloma virus-independent. Hence, GAS is now classified as an human papilloma virus-independent gastric type. Because clinical studies have reported that GAS is refractory to conventional treatments such as chemotherapy and radiotherapy, especially at an advanced stage, and has aggressive features with widespread dissemination to unusual sites, such as the omentum, peritoneum and distant organs, it is urgent to establish new treatment strategies by comparing the molecular profiles of human papilloma virus-associated adenocarcinomas. A series of genetic mutations characteristic to GAS encourage the development of future treatment strategies such as targeted therapy and immunotherapy.

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.