Association between timing of post-operative radiotherapy and recurrence in patients with endometrial carcinoma, Mansoura University experience.

Introduction: Endometrial cancer is the most common gynecological tumor in developed countries, and its incidence is increasing. Adjuvant radiation therapy (RT) is an important line of treatment for this disease with marked effect as regarding improvement of local control and survival. We analyzed the impact of delay between surgery and RT initiation in patients with endometrial carcinoma.
Patient and methods: 256 patients with endometrial carcinoma who received adjuvant RT after hysterectomy from Jan 2012 and Dec 2014 were included in the study. All patients operated by hysterectomy, oophorectomy, and pelvic and par-aortic lymph node evaluation. The time interval between hysterectomy and the start of RT was calculated and according to that, patients divided in 2 groups; group 1 who received RT before 8weeks and group 2 received RT after 8 weeks from surgery. The effects of time interval on recurrence-free survival (RFS) and overall survival (OAS) were calculated.
Results: At the end of the study and after mean over all time of follow up 64.55 +/- 17.76 months, 48 cases (18.8%) recorded to develop recurrent disease and 40 cases (15.6%) were died. The RT was delivered with brachytherapy alone in 64 cases (25%), pelvic RT alone in 133 cases (52%), or both 59 cases (23%). A total of 140 (54.7%) patients started their RT before 8 weeks after radical surgery (group 1) and 116 patients (45.4%) started 8 weeks after surgery (group 2). Tumor recurrence was significantly associated with treatment delay. 34 cases (29.3%) in group 2 developed tumor recurrence compared to only 14 cases (10%) in group 1. Only 11 patients (7.9%) of group 1 died compared to 29 patients (25%) in group 2. the median recurrence free survival time was 79.5 months in group 1 compared to 64.845 months in group 2. The median OAS for group 1 was 82.043 months compared to 70.509 months in group 2 with significant P-value in both. On multivariate analysis and besides the late starting of RTH, also grade III and stage III disease were found to be significant factors as independent predictors of mortality and recurrence.
Conclusions: Starting adjuvant RT after 8 weeks for cases with endometrial carcinoma is associated with worse survival endpoints.