Comparison of survival outcomes and effects of therapy between subtypes of high-grade endometrial cancer - a population-based study.

BACKGROUND: Similarities in outcome between grade 3 endometrioid cancer and non-endometrioid histologies have been reported by a number of studies. Other reports, however, stated a significantly better prognosis for G3 endometrioid compared to type II histology. In this population-based study, we compared the outcome and treatment approaches of high-grade endometrial cancer patients with FIGO stages I-III depending on their histology. MATERIAL AND METHODS: 284 high-grade endometrial cancer patients diagnosed between 1998 and 2015 were retrospectively analyzed. Overall survival (OS), recurrence-free survival (RFS), and recurrence rates were compared depending on histology. RESULTS: Type I G3 patients had a statistically significant OS advantage over women suffering from type II carcinoma (HR 1.527, 95%-CI 1.024-2.276; p = 0.038) and carcinosarcoma (HR 2.106, 95%-CI 1.270-3.493; p = 0.004) in univariable and multivariable Cox-regression analysis. RFS in Type I G3 was significantly superior compared to patients with carcinosarcoma (HR 1.719, 95%-CI 1.018-2.901; p = 0.043) and not significantly superior to type II patients (HR 1.368, 95%-CI 0.920-2.036; p = 0.122). Cumulative recurrence rates were significantly higher in carcinosarcoma compared to type I G3 (HR 2.217, 95%-CI 1.096-4.485; p = 0.027) in univariable analysis, but not after risk adjustment (HR of 1.472, 95%-CI 0.654-3.311; p = 0.350). CONCLUSION: The prognosis of patients with type I G3 endometrial cancer patients seems to be significantly superior to patients with type II cancer and particularly carcinosarcoma. Systematic LND seemed to be beneficial in all of the three subtypes. The benefit of adjuvant treatment methods may differ between histologies.

Does post-operative radiochemotherapy improve survival in high-grade endometrial cancer patients? Results of a population-based cohort analysis of a cancer registry.

PURPOSE: Adjuvant treatment of high-grade endometrial cancer varies greatly due to the lack of definitive results from controlled randomized trials on the subject. In a retrospective study, we sought to investigate the influence of post-operative radio-, chemo, and radiochemotherapy on survival time and recurrence rates among high-grade endometrial cancer patients. METHODS: 284 high-grade endometrial cancer patients (FIGOI-III, or unknown classification) diagnosed between 1998 and 2015 were retrospectively analyzed. All patients underwent surgery. Overall survival (OS), recurrence-free survival (RFS), and recurrence rates were compared for post-operative treatment modalities of radiotherapy alone (RT), chemotherapy alone (CTX), radiochemotherapy (RCT), and observation (OBS). RESULTS: Post-operative RCT and RT resulted in a significantly improved 5-year OS of 94.1% (HR 0.104, CI 0.013-0.809) and 62.1% (HR 0.615, CI 0.390-0.969), respectively, compared to 43.6% for OBS. CTX did not significantly improve OS leading to a 5-year OS of 56.5% (HR 0.783, CI 0.224-2.740). 5-year recurrence rate was lowest for patients treated with RCT (5.3%). 5-year RFS was 94.1% for the RCT group and proved to be significantly superior to 58.8% for RT (HR 9.034, CI 1.184-68.948), 56% for CTX (HR 12.738, CI 1.337-121.346), and 37.4% for OBS (HR 16.407, CI 2.127-126.575), respectively. In comparison with OBS, RT alone resulted in a significant improvement in RFS (HR 0.551, CI 0.354-0.856). CONCLUSIONS: Our retrospective population-based study indicates a survival benefit from treating high-grade endometrial cancer with post-operative RCT. Randomized controlled trials are needed to minimize potential confounding parameters and further clarify the subject.