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.