Retrospective study of neoadjuvant radiotherapy for locally advanced surgically inoperable endometrial carcinoma

Surgically inoperable locally advanced endometrial cancer is associated with poor prognosis. The optimal treatment strategy remains controversial. In this study, we report the treatment outcomes and adverse effects of neoadjuvant radiotherapy followed by definitive surgery for locally advanced surgically inoperable endometrial cancer in our institution.

Between January 2010 and June 2024, patients with locally advanced upfront inoperable endometrial cancer who received neoadjuvant radiotherapy were retrospectively reviewed. Margin status, pathological response, and toxicities were reported. Kaplan-Meier analysis was performed to estimate progression-free survival and overall survival.

A total of 37 consecutive patients were included. All had cervical involvement. A total of 26 patients (70%) had parametrial involvement, and 10 patients (27%) had nodal involvement. After external beam radiotherapy, 33 patients (89%) received brachytherapy. Among the patients, 24 (65%) had concurrent platinum-based chemotherapy. After neoadjuvant radiotherapy, 33 patients (89%) were deemed operable. Definitive surgery was eventually performed in 31 patients (84%). The complete resection rate was 100% (n = 31). A pathological complete response was achieved in 9 patients (29%), while 7 patients (23%) had microscopic disease only. Downstaging to stage I or below occurred in 19 patients (61%). The median follow-up was 74 months. The 5-year progression-free survival and overall survival rates were 71.9% and 73.4% respectively. One patient experienced grade 3 diarrhea during radiotherapy. Surgical complications of grade 2 to 3 severity occurred in 3 patients (10%). Chronic radiotherapy toxicities of grade 3 or higher were also observed in 3 patients (10%).

Neoadjuvant radiotherapy is feasible for locally advanced endometrial cancer, with high complete resection, pathological complete response, and locoregional control rates in a single center. Further research is warranted to optimize treatment efficacy and toxicities in the image-guided brachytherapy era.