Objective: 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. Methods: A decision-analytic model was evaluated using the following variables and their impact on cost-effectiveness: 1) hospital treatment volume (low-, intermediate-, and highvolume 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. Results: A base-case analysis showed that the incremental cost-effectiveness ratio at high-volume centers was below a willingness-to-pay (WTP) threshold of ¥5,000,000with 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 lowvolume 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 lowrisk groups, respectively. Conclusion Treatment at high-volume centers is the most cost-effective strategy for guiding treatment centralization in patients with endometrial cancer.

Objective: 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. Methods: A decision-analytic model was evaluated using the following variables and their impact on cost-effectiveness: 1) hospital treatment volume (low-, intermediate-, and highvolume 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. Results: A base-case analysis showed that the incremental cost-effectiveness ratio at high-volume centers was below a willingness-to-pay (WTP) threshold of ¥5,000,000with 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 lowvolume 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 lowrisk groups, respectively. Conclusion Treatment at high-volume centers is the most cost-effective strategy for guiding treatment centralization in patients with endometrial cancer.

Objective: 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. Methods: A decision-analytic model was evaluated using the following variables and their impact on cost-effectiveness: 1) hospital treatment volume (low-, intermediate-, and highvolume 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. Results: A base-case analysis showed that the incremental cost-effectiveness ratio at high-volume centers was below a willingness-to-pay (WTP) threshold of ¥5,000,000with 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 lowvolume 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 lowrisk groups, respectively. Conclusion Treatment at high-volume centers is the most cost-effective strategy for guiding treatment centralization in patients with endometrial cancer.

Objective: To examine the effectiveness of progestin re-treatment for recurrent endometrial intraepithelial neoplasia (EIN), atypical endometrial hyperplasia (AH) and endometrial cancer (EC) following initial fertility-sparing treatment. Methods: A comprehensive systematic review and meta-analysis were conducted by an Expert Panel of the Japan Society of Gynecologic Oncology Endometrial Cancer Committee. Multiple search engines, including PubMed/MEDLINE and the Cochrane Database, were searched in December 2021 using the keywords “Endometrial neoplasms,” “Endometrial hyperplasia,” “Endometrial intraepithelial neoplasia,” “Fertility preservation,” “Progestins,” AND “Recurrence.” Cases describing progestin re-treatment for recurrent EIN, AH and EC were compared with cases that underwent conventional hysterectomy. The primary outcomes were survival and disease recurrence, and the secondary outcome was pregnancy. Results: After screening 238 studies, 32 with results for recurrent treatment were identified. These studies included 365 patients (270 received progestin re-treatment and 95 underwent hysterectomy). Most progestin re-treatment involved medroxyprogesterone acetate or megestrol acetate (94.5%). Complete remission (CR) following progestin re-treatment was achieved in 219 (81.1%) cases, with 3-, 6- and 9-month cumulative CR rates of 22.8%, 51.7% and 82.6%, respectively. Progestin re-treatment was associated with higher risk of disease recurrence than conventional hysterectomy was (odds ratio [OR]=6.78; 95% confidence interval [CI]=1.99–23.10), and one patient (0.4%) died of disease. Fifty-one (14.0%) women became pregnant after recurrence, and progestin re-treatment demonstrated a possibility of pregnancy (OR=2.48; 95% CI=0.94–6.58). Conclusion This meta-analysis suggests that repeat progestin therapy is an effective option for women with recurrent EIN, AH and EC, who wish to retain their fertility.

Objective: Owing to the potential benefits of minimally invasive hysterectomy for endometrial cancer, the practice pattern has recently shifted in Japan. This study examined the trends in minimally invasive surgery (MIS) in patients with endometrial cancer in Japan. Methods: This retrospective observational study examined the Japan Society of Obstetrics and Gynecology Tumor Registry database between 2015–2019. This study examined the time-specific proportion change and predictors of MIS use in initial endometrial cancer treatment in Japan, and compared it with the use of abdominal surgery. Additionally, the association between hospital surgical treatment volume and MIS use was examined. Results: A total of 14,059 patients (26.5%) underwent minimally invasive hysterectomy, and 39,070 patients (73.5%) underwent abdominal hysterectomy in the study period. Patients who underwent MIS were more likely to be treated at high-volume centers, younger, central, or western Japan residents, registered in recent years, and had a tumor with stage I disease, type 1 histology, and less myometrial invasion (all adjusted p<0.05). The proportion of MIS treatments increased from 19.1% in 2015 to 34.3% in 2019 (p<0.001). On multivariable analysis, treatment at high-volume centers was a contributing factor for MIS (adjusted odds ratio=3.85; 95% confidence interval=3.44–4.30). MIS at high-volume centers increased significantly from 24.8% to 41.0% (p<0.001) during the study period, whereas MIS at low-volume centers remained at median 8.8%. Conclusion MIS has increased significantly in recent years, accounting for nearly 34% of surgical management of endometrial cancer in Japan. High-volume treatment centers take the lead in performing MIS.

Objective: 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. Methods: 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. Results: 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). Conclusion 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.

Objective: The study compared the treatment outcomes of surgery versus radiotherapy, including concurrent chemoradiotherapy, in stage Ib2–IIb cervical adenocarcinoma patients in Japan. Methods: Of 57,470 patients diagnosed with stage I–IV cervical cancer from January 2001–December 2011, 1,932 patients with stage Ib2–IIb cervical adenocarcinoma were initially treated by surgery or radiotherapy. The primary endpoint was 5-year overall survival (OS) in all and 614 propensity score-matched (PSM) patients (307 per group). We compared OS and prognosis factors based on age, primary stage, and treatment arm. Results: In Japan, >80% (n=1,573) of stage Ib2–IIb cervical adenocarcinoma patients underwent surgery. The 5-year OS of surgery vs. radiotherapy groups were 82.1% (n=704) vs. 79.7% (n=59) (hazard ratio [HR]=1.494; 95% confidence interval [CI]=0.826–2.702; p=0.181) for stage Ib2, 76.6% (n=239) vs. 66.7% (n=54) (HR=1.679; 95% CI=0.986–2.858; p=0.053) for stage IIa, and 71.1% (n=630) vs. 58.9% (n=246) (HR=1.711; 95% CI=1.341–2.184; p<0.001) for stage IIb. In 614 PSM patients balanced for age and carcinoma stage Ib2–IIb, the 5-year OS of surgery vs. radiation groups was 73.0% (n=307) vs. 65.5% (n=307) (HR=1.394; 95% CI=1.044–1.860; p=0.023). In multivariable analysis, age (HR=1.293; 95% CI=1.045–1.601; p=0.018), treatment arm, radiotherapy (HR=1.556; 95% CI=1.253–1.933; p<0.001), and stage IIb (HR=1.783; 95% CI=1.443–2.203; p=0.018) were independent prognosis factors for 5-year OS in stage Ib2–IIb adenocarcinoma patients. Conclusion Age (>65 years), treatment arm (radiotherapy), and stage IIb significantly affect OS in cervical adenocarcinoma patients. Surgery may be considered for <65-year-old patients with stage IIb adenocarcinoma.

Objective: To assess the efficacy of the FIGO 2018 classification system for nodal-specific classifications for early-stage cervical cancer; specifically, to examine the impact of nodal metastasis on survival and the effect of postoperative treatments, according to histological subtypes. Methods: This society-based retrospective observational study in Japan examined 16,539 women with the 2009 FIGO stage IB1 cervical cancer who underwent primary surgical treatment from 2004 to 2015. Associations of cause-specific survival (CSS) with nodal metastasis and postoperative adjuvant therapy were examined according to histology type (squamous cell carcinoma [SCC], n=10,315; and non-SCC, n=6,224). Results: The nodal metastasis rate for SCC was higher than that for non-SCC (10.7% vs. 8.3%, p<0.001). In multivariable analysis, the impact of nodal metastasis on CSS was greater for non-SCC tumors (adjusted-hazard ratio [HR], 3.11; 95% confidence interval [CI], 2.40–4.02) than for SCC tumors (adjusted-HR, 2.20; 95% CI, 1.70–2.84; p<0.001). Propensity score matching analysis showed significantly lower CSS rates for women with pelvic nodal metastasis from non-SCC tumors than from SCC tumors (5-year CSS rate, 75.4% vs. 90.3%, p<0.001). The CSS rates for women with nodal metastasis in SCC histology were similar between the postoperative concurrent chemoradiotherapy/radiotherapy and chemotherapy groups (89.2% vs. 86.1%, p=0.42), whereas those in non-SCC histology who received postoperative chemotherapy improved the CSS (74.1% vs. 67.7%, p=0.043). Conclusion The node-specific staging system in the 2018 FIGO cervical cancer classification is applicable to both non-SCC tumors and SCC tumors; however, the prognostic significance of nodal metastases and efficacy of postoperative therapies vary according to histology.

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.

No abstract available.
Drug Therapy ; Japan ; Joints ; Ovarian Neoplasms