Objective: Uterine carcinosarcoma (UCS) is uncommon high-grade endometrial cancer with limited treatment options. We evaluated the prognostic significance of human epidermal growth factor receptor 2 (HER2) expression and HER2 gene amplification within large cohorts of UCS, and clarify clinicopathologic characteristics of HER2-low UCS. Methods: We examined HER2 protein expression in 148 patients of UCS using in vivo diagnostic HER2 immunohistochemistry (IHC) kits and HER2 gene amplification using fluorescence in situ hybridization (FISH) in 72 patients. Results: HER2 IHC score was evaluated according to the latest American Society of Clinical Oncology/College of American Pathologists criteria for gastric cancer, which was negative in 41 patients, low expression of 1+ was observed in 57 patients, and HER2 high expression was observed in 50 patients (2+ in 38 and 3+ in 12 patients). There was no significant statistical difference in clinicopathological characteristics based on HER2 protein expression status.HER2 negative and low expression compared to high expression revealed poor overall survival in stage I/ II. The concordance between IHC and FISH results were relatively low compared to other cancer types (HER2 IHC score 1+, 2+, and 3+ were 5%, 15%, and 50%), and combining these results was not efficient as a prognostic factor in UCS. In contrast, the HER2 IHC score alone was a prognostic factor in stage I/II UCS. HER2 low group did not show specific clinicopathologic features. Conclusion Since the HER2 IHC score low in advanced UCS is a predictive factor, stratification of UCS using HER2 IHC score for HER2 IHC score low group and developing adjuvant therapy may be proposed in the near future.

Objective: To identify a relatively high-risk population in postoperative intermediate-risk cervical cancer and evaluate the effect of platinum-based adjuvant chemotherapy (CT). Methods: We retrospectively reviewed the medical records of patients with stage IA2-IIA cervical cancer who had been treated with radical hysterectomy and pelvic lymphadenectomy and classified as the intermediate-risk group for recurrence by postoperative pathological examination from January 2007 to December 2018 at 3 medical centers in Japan. First, patients with intermediate-risk were stratified by histological type and the number of intermediaterisk factors (IRF; large tumor diameter, lymph vascular space invasion, and deep cervical stromal invasion) and then divided into 2 groups: high and low-risk population (estimated 5-year recurrence-free survival [RFS] rate with no further therapy [NFT] <90% and ≥90%, respectively). Second, the efficacy of CT for the high-risk population was evaluated by comparing RFS and overall survival (OS) between the patients receiving CT and those with NFT. Results: In total, 133 patients were included in the analysis. Among patients with squamous cell carcinoma (SCC) with all IRF or those with non-SCC with 2 to 3 IRF, the 5-year estimated RFS was <90% when treated with NFT. In this population, adjuvant CT was significantly superior to NFT regarding RFS (log-rank, p=0.014), although there was no statistical difference in OS. Conclusion Patients with SCC with all 3 IRFs and those with non-SCC with 2 to 3 IRFs were at high risk for recurrence. Adjuvant CT is a valid treatment option for these populations.

Objective: Uterine carcinosarcoma (UCS) is uncommon high-grade endometrial cancer with limited treatment options. We evaluated the prognostic significance of human epidermal growth factor receptor 2 (HER2) expression and HER2 gene amplification within large cohorts of UCS, and clarify clinicopathologic characteristics of HER2-low UCS. Methods: We examined HER2 protein expression in 148 patients of UCS using in vivo diagnostic HER2 immunohistochemistry (IHC) kits and HER2 gene amplification using fluorescence in situ hybridization (FISH) in 72 patients. Results: HER2 IHC score was evaluated according to the latest American Society of Clinical Oncology/College of American Pathologists criteria for gastric cancer, which was negative in 41 patients, low expression of 1+ was observed in 57 patients, and HER2 high expression was observed in 50 patients (2+ in 38 and 3+ in 12 patients). There was no significant statistical difference in clinicopathological characteristics based on HER2 protein expression status.HER2 negative and low expression compared to high expression revealed poor overall survival in stage I/ II. The concordance between IHC and FISH results were relatively low compared to other cancer types (HER2 IHC score 1+, 2+, and 3+ were 5%, 15%, and 50%), and combining these results was not efficient as a prognostic factor in UCS. In contrast, the HER2 IHC score alone was a prognostic factor in stage I/II UCS. HER2 low group did not show specific clinicopathologic features. Conclusion Since the HER2 IHC score low in advanced UCS is a predictive factor, stratification of UCS using HER2 IHC score for HER2 IHC score low group and developing adjuvant therapy may be proposed in the near future.

Objective: To identify a relatively high-risk population in postoperative intermediate-risk cervical cancer and evaluate the effect of platinum-based adjuvant chemotherapy (CT). Methods: We retrospectively reviewed the medical records of patients with stage IA2-IIA cervical cancer who had been treated with radical hysterectomy and pelvic lymphadenectomy and classified as the intermediate-risk group for recurrence by postoperative pathological examination from January 2007 to December 2018 at 3 medical centers in Japan. First, patients with intermediate-risk were stratified by histological type and the number of intermediaterisk factors (IRF; large tumor diameter, lymph vascular space invasion, and deep cervical stromal invasion) and then divided into 2 groups: high and low-risk population (estimated 5-year recurrence-free survival [RFS] rate with no further therapy [NFT] <90% and ≥90%, respectively). Second, the efficacy of CT for the high-risk population was evaluated by comparing RFS and overall survival (OS) between the patients receiving CT and those with NFT. Results: In total, 133 patients were included in the analysis. Among patients with squamous cell carcinoma (SCC) with all IRF or those with non-SCC with 2 to 3 IRF, the 5-year estimated RFS was <90% when treated with NFT. In this population, adjuvant CT was significantly superior to NFT regarding RFS (log-rank, p=0.014), although there was no statistical difference in OS. Conclusion Patients with SCC with all 3 IRFs and those with non-SCC with 2 to 3 IRFs were at high risk for recurrence. Adjuvant CT is a valid treatment option for these populations.

Objective: Uterine carcinosarcoma (UCS) is uncommon high-grade endometrial cancer with limited treatment options. We evaluated the prognostic significance of human epidermal growth factor receptor 2 (HER2) expression and HER2 gene amplification within large cohorts of UCS, and clarify clinicopathologic characteristics of HER2-low UCS. Methods: We examined HER2 protein expression in 148 patients of UCS using in vivo diagnostic HER2 immunohistochemistry (IHC) kits and HER2 gene amplification using fluorescence in situ hybridization (FISH) in 72 patients. Results: HER2 IHC score was evaluated according to the latest American Society of Clinical Oncology/College of American Pathologists criteria for gastric cancer, which was negative in 41 patients, low expression of 1+ was observed in 57 patients, and HER2 high expression was observed in 50 patients (2+ in 38 and 3+ in 12 patients). There was no significant statistical difference in clinicopathological characteristics based on HER2 protein expression status.HER2 negative and low expression compared to high expression revealed poor overall survival in stage I/ II. The concordance between IHC and FISH results were relatively low compared to other cancer types (HER2 IHC score 1+, 2+, and 3+ were 5%, 15%, and 50%), and combining these results was not efficient as a prognostic factor in UCS. In contrast, the HER2 IHC score alone was a prognostic factor in stage I/II UCS. HER2 low group did not show specific clinicopathologic features. Conclusion Since the HER2 IHC score low in advanced UCS is a predictive factor, stratification of UCS using HER2 IHC score for HER2 IHC score low group and developing adjuvant therapy may be proposed in the near future.

Objective: To identify a relatively high-risk population in postoperative intermediate-risk cervical cancer and evaluate the effect of platinum-based adjuvant chemotherapy (CT). Methods: We retrospectively reviewed the medical records of patients with stage IA2-IIA cervical cancer who had been treated with radical hysterectomy and pelvic lymphadenectomy and classified as the intermediate-risk group for recurrence by postoperative pathological examination from January 2007 to December 2018 at 3 medical centers in Japan. First, patients with intermediate-risk were stratified by histological type and the number of intermediaterisk factors (IRF; large tumor diameter, lymph vascular space invasion, and deep cervical stromal invasion) and then divided into 2 groups: high and low-risk population (estimated 5-year recurrence-free survival [RFS] rate with no further therapy [NFT] <90% and ≥90%, respectively). Second, the efficacy of CT for the high-risk population was evaluated by comparing RFS and overall survival (OS) between the patients receiving CT and those with NFT. Results: In total, 133 patients were included in the analysis. Among patients with squamous cell carcinoma (SCC) with all IRF or those with non-SCC with 2 to 3 IRF, the 5-year estimated RFS was <90% when treated with NFT. In this population, adjuvant CT was significantly superior to NFT regarding RFS (log-rank, p=0.014), although there was no statistical difference in OS. Conclusion Patients with SCC with all 3 IRFs and those with non-SCC with 2 to 3 IRFs were at high risk for recurrence. Adjuvant CT is a valid treatment option for these populations.

Objective: In Japan, perioperative prophylaxis of pulmonary embolism (PE) in gynecologic cancer patients with preoperative asymptomatic venous thromboembolism (VTE) has not been well established yet. The GOTIC-VTE trial was a prospective, multi-center, single-arm clinical trial to investigate the prevention of postoperative symptomatic PE onset by seamless anticoagulant therapy from the preoperative period to 4 weeks after surgery instead of using intermittent pneumatic compression. Methods: Anticoagulant therapy was started immediately after asymptomatic VTE diagnosis and stopped preoperatively according to the rules of each institution. Unfractionated heparin administration was resumed within 12 hours postoperatively, and this was followed by the switch to low-molecular-weight heparin and subsequently, edoxaban; this cycle was continued for 28 days. Primary outcome was the occurrence of symptomatic PE in 28 days postoperatively. Secondary outcomes were the incidence of VTE-related events in 28 days and 6 months postoperatively and protocol-related adverse events. Results: Between February 2018 and September 2020, 99 patients were enrolled; of these, 82patients were assessed as the full analysis set, including 58 for ovarian cancer, fallopian tube, or peritoneal cancer; 21 for endometrial cancer; and 3 for cervical cancer. No symptomatic PE was observed within 28 days postoperatively; two patients had bleeding events (major bleeding and clinically relevant nonmajor bleeding) and three had grade 3 adverse events (increased alanine transaminase, aspartate aminotransferase, or gamma-glutamyl transferase). Conclusion The multifaceted perioperative management for gynecologic malignancies with asymptomatic VTE effectively prevented postoperative symptomatic PE.Trial Registration: JRCT Identifier: jRCTs031180124

Objective: This study aimed to evaluate mesothelin (MSLN) expression and determine its clinical significance and correlation with human epidermal growth factor receptor 2 (HER2) expression in gynecological carcinosarcoma. Methods: We retrospectively evaluated patients with uterine carcinosarcoma (UCS) and ovarian carcinosarcoma (OCS) who underwent surgery between 1997 and 2019.Immunohistochemical staining of formalin-fixed, paraffin-embedded specimens for MSLN (clone SP74) and HER2 (clone 4A5) was also performed. MSLN was scored using the H-score and 4-tired scoring system (0–3+). MSLN positivity was defined as any positive cell at any intensity, while high MSLN expression was defined as an intensity of ≥2+ in ≥30% of tumor cells. HER2 expression was scored according to modified 2018 American Society of Clinical Oncology/College of American Pathologists criteria. Results: A total of 128 patients were recruited, including 119 with UCS and 9 with OCS.All cases in UCS exhibited MSLN positivity, and 33.9% showed high-MSLN expression.Clinicopathological characteristics were not significantly associated with high or low-MSLN expression. However, the high-MSLN group showed more prolonged overall survival (OS) than the low-MSLN group (not assessed vs. 36.8 months; hazard ratio=0.48, 95% confidence interval=0.26–0.89, p=0.016). HER2-high patients had higher MSLN expression than HER2-negative patients. In high-MSLN and low-MSLN expression groups, HER2 status did not affect OS. OCS showed 100% MSLN positivity, with 66.6% high-MSLN. Conclusion MSLN expression is widely observed in gynecological carcinosarcomas.Moreover, high-MSLN expression is a favorable prognostic factor for UCS. MSLN could be a promising therapeutic target for UCS, even in the era of anti-HER2 therapy.

Objective: The efficacy of pembrolizumab in patients with microsatellite instability (MSI)-high cancers has been reported; however, the differences in efficacy according to the subtypes of MSI-high endometrial cancers (ECs) remain unclear. MSI-high ECs are classified into at least 3 groups based on their molecular characteristics: MLH1 hypermethylated, Lynch-like syndrome (LLS)-associated, and Lynch syndrome (LS)-associated cancers. This study aimed to investigate whether the efficacy of pembrolizumab differs among these 3 groups, and if so, whether EPM2AIP1 immunohistochemistry (IHC), which correlates with MLH1 promoter methylation, can be used to rule out MLH1 methylation cases. Methods: This study included 12 patients with MSI-high EC who received pembrolizumab treatment. Patients were categorized into 3 groups based on MLH1 methylation analysis and the Amsterdam Criteria: MLH1 hypermethylated (sporadic [SP]), LLS-associated, and LS-associated. Patients’ medical records were retrospectively reviewed, and the efficacy of treatment was evaluated based on the response rate using the Response Evaluation Criteria in Solid Tumors version 1.1. Results: The overall response rate was 75% (3/4) in the SP group, while it was 100% including one complete response patient in the LLS-associated and the LS-associated group, respectively. The sensitivity and positive predictive value of EPM2AIP1 IHC for MLH1 methylation were 100% and 66.7%, respectively. Conclusion Pembrolizumab may be more effective in LLS and LS-associated groups.EPM2AIP1 IHC was less predictive than MLH1 methylation analysis; however, it may be useful for ruling out MLH1 methylation cases due to its high sensitivity. Further studies are needed to determine whether EPM2AIP1 IHC can predict pembrolizumab efficacy.

Objective: In Japan, perioperative prophylaxis of pulmonary embolism (PE) in gynecologic cancer patients with preoperative asymptomatic venous thromboembolism (VTE) has not been well established yet. The GOTIC-VTE trial was a prospective, multi-center, single-arm clinical trial to investigate the prevention of postoperative symptomatic PE onset by seamless anticoagulant therapy from the preoperative period to 4 weeks after surgery instead of using intermittent pneumatic compression. Methods: Anticoagulant therapy was started immediately after asymptomatic VTE diagnosis and stopped preoperatively according to the rules of each institution. Unfractionated heparin administration was resumed within 12 hours postoperatively, and this was followed by the switch to low-molecular-weight heparin and subsequently, edoxaban; this cycle was continued for 28 days. Primary outcome was the occurrence of symptomatic PE in 28 days postoperatively. Secondary outcomes were the incidence of VTE-related events in 28 days and 6 months postoperatively and protocol-related adverse events. Results: Between February 2018 and September 2020, 99 patients were enrolled; of these, 82patients were assessed as the full analysis set, including 58 for ovarian cancer, fallopian tube, or peritoneal cancer; 21 for endometrial cancer; and 3 for cervical cancer. No symptomatic PE was observed within 28 days postoperatively; two patients had bleeding events (major bleeding and clinically relevant nonmajor bleeding) and three had grade 3 adverse events (increased alanine transaminase, aspartate aminotransferase, or gamma-glutamyl transferase). Conclusion The multifaceted perioperative management for gynecologic malignancies with asymptomatic VTE effectively prevented postoperative symptomatic PE.Trial Registration: JRCT Identifier: jRCTs031180124