Upfront radiotherapy with brachytherapy for medically inoperable and unresectable patients with high-risk endometrial cancer

Objectives: Comprehensive surgery with adjuvant therapy is standard of care for high-risk endometrial cancers, whereas upfront radiotherapy with brachytherapy is indicated for inoperable/unresectable patients, irrespective of risk. We evaluated outcomes for inoperable/unresectable patients with high-risk endometrial cancer (HREC: stage III and/or grade 3) and low-risk endometrial cancer (LREC: stage I/II and grade 1/2) treated with upfront radiotherapy.

Methods: Twenty-nine patients with inoperable/unresectable endometrial cancer were treated with upfront radiotherapy at an academic medical center from 2012 to 2019. Cancer-specific survival (CSS), overall survival (OS), and recurrence rates between patients with HREC and LREC were compared.

Results: Median follow-up was 17.0 months (range 3.7-54.0). Twenty cancers were stage I + II and nine were stage III. Twenty-one cancers were grade 1 + 2 and eight were grade 3. Thirteen patients (45%) had HREC. Twenty-five patients received radiotherapy/chemoradiotherapy for primary treatment, while 4 patients received chemoradiotherapy before surgery. All patients underwent high dose rate brachytherapy (HDR) with 7 receiving HDR alone and 22 receiving external beam radiation and HDR. Two-year CSS was 100% for both HREC and LREC patients (log-rank p = 0.32). There was no OS difference between HREC and LREC patients (2-year: 73% vs. 77%; log-rank p = 0.33). Four HREC and 1 LREC patients recurred with one local recurrence in each group. There were no acute grade ≥3 and two late grade ≥3 gastrointestinal/genitourinary toxicities.

Conclusions: Upfront radiotherapy for inoperable/unresectable HREC patients was well tolerated with high local control and CSS rates. Upfront radiotherapy with brachytherapy remains important even for high-risk inoperable and unresectable endometrial cancer patients.