Treatment results of image-guided high-dose-rate interstitial brachytherapy for pelvic recurrence of uterine cancer.

Purpose: We analyzed clinical data to evaluate the effectiveness of image-guided high-dose-rate interstitial brachytherapy (HDR-ISBT) for pelvic recurrence of uterine cancer.

Methods And Materials: Between 2003 and 2011, 56 patients were treated with HDR-ISBT with or without external beam radiotherapy (EBRT). The median followup time was 33 months (range, 1-109 months). Pre-ISBT treatments included radical hysterectomy for 35 patients (Group A), radical hysterectomy with postoperative radiotherapy for 8 patients (Group B), and radical radiotherapy for 13 patients (Group C). We initiated MRI-assisted CT-based planning for the last 49 patients. The median ISBT single fraction dose was 6 Gy. The median total doses were 30 and 54 Gy with and without EBRT (range, 30-50 Gy) for Group A, respectively and 48 Gy without EBRT for Groups B and C.

Results: The 3-year local control (LC) rates were 85%, 75%, and 46% for Groups A, B, and C, respectively (p = 0.017). The 3-year LC rates were 84%, 73%, and 33% for clinical target volume at the time of HDR-ISBT of <10, 10-29, and ≥30 cc, respectively (p = 0.005). The 3-year LC results tended to be higher for patients whose D100 (clinical target volume) was equal or higher than 67.1 Gy (p = 0.098). A total of 13 late complications of Grades 3-5 occurred in 11 patients (20%).

Conclusions: Our image-guided HDR-ISBT for pelvic recurrence of uterine cancer provided good treatment outcomes. The treatment results for patients who underwent radical surgery with or without postoperative radiotherapy are better than those for patients who underwent radical radiotherapy.