Purpose: To evaluate clinical outcomes for women with recurrent endometrial cancer treated with 3D image-guided brachytherapy
Methods and materials: 44 women, of whom 13 had received prior RT, received salvage RT for vaginal recurrence from 9/03 to 8/11. HDR or LDR interstitial brachytherapy was performed under MR or CT guidance in 35 patients (80%); 9 (20%) had CT-guided HDR cylinder brachytherapy. The median cumulative dose in EQD2 was 75.5 Gy. Actuarial estimates of local failure (LF), disease-free (DFS) and overall survival (OS) were calculated by Kaplan-Meier.
Results: Histologic subtypes were endometrioid (EAC, 33), papillary serous/clear cell (UPSC/CC, 5) and carcinosarcoma (CS, 6). The 2-year DFS/OS rates were 75%/89% for EAC and 11%/24% for UPSC/CC/CS (both p<0.01). On MVA, high tumor grade was associated with recurrence (HR 3.2 for grade 2, 9.6 for grade 3, p<0.01). The LF rate at 2 years was 4% for patients without versus 39% for those with prior RT (p=0.1). Patients who had prior RT received lower cumulative doses at recurrence (66.5 Gy vs. 74.4 Gy, p<0.01). The 2-year DFS/OS rates with and without prior RT were 26%/55% and 72%/80% (both p=0.1). Four patients (9%) experienced grade 3 late toxicity, including 3 of 13 (23%) in the re-irradiation setting and 1 of 31 (3%) with no prior radiotherapy.
Discussion: 3D image-guided brachytherapy results in excellent local control for women with recurrent endometrial cancer, particularly with cumulative EQD2 doses greater than 70 Gy. Successful salvage of vaginal recurrence is related to tumor grade and histologic subtype.
Keywords: Image-guided brachytherapy; Recurrent endometrial cancer; Salvage radiotherapy.
© 2013.