Improving locoregional outcome in high-intermediate-risk and high-risk stage I endometrial cancer with surgical staging followed by brachytherapy.

Purpose: This study aims to assess the locoregional efficacy of postoperative vaginal brachytherapy (VBT) alone in patients undergoing surgical staging for early-stage high-intermediate-risk (HIR) and high-risk (HR) endometrial cancer.

Materials and methods: One hundred and four patients with early-stage HIR and HR endometrial cancer who underwent surgical staging were treated with adjuvant VBT alone. The patients with stage Ib, grade I-III, stage Ia, grade III, lower uterine segment involvement, and lymphovascular invasion (LVI) were included to study.

Results: The 5- and 10-year overall survival (OS) rates were 87% and 76%, respectively. The 5- and 10-year DFS rates were 86% and 86%, respectively. Among the patients, 92% had endometrioid adenocarcinoma, 2% had undifferentiated carcinoma, 2% had serous papillary carcinoma, and 4% had clear-cell carcinoma. Of the patients, 63% had stage Ib disease, while 37% had stage Ia disease. None of the patients had vaginal or pelvic lymph node recurrence, whereas two had para-aortic lymph node metastasis, one had surgical scar recurrence, one had para-aortic lymph node and brain metastasis, and one had lung metastasis. The presence of lymphatic invasion was found to be a statistically significant prognostic factor for increased distant metastasis rates (p = 0.020). Lymphatic invasion was also regarded as an independent prognostic factor for metastasis-free survival (p = 0.044).

Conclusion: Our study results suggest that postoperative VBT alone is an effective and safe treatment modality with low complication in patients undergoing surgical staging for HIR and HR endometrial cancer.