Radiation therapy in stage III ovarian cancer following surgery and chemotherapy: Prognostic factors, patterns of relapse, and toxicity: A preliminary report

Abstract Twenty patients with FIGO stage III epithelial ovarian cancer who had undergone maximum cytoreductive surgery (including pelvic and paraaortic lymph node dissection) and combination chemotherapy (4–10 cycles, median 6) were treated with irradiation to the abdomen and pelvis with 30 Gy followed by diaphragmatic/paraaortic and pelvis boost fields to 42 and 51.6 Gy, respectively. Second-look laparotomy was not performed. Seventeen of 20 patients completed the planned course of radiation. In 2 cases, failure to complete treatment was related to acute hematologic toxity, and 1 patient refused further treatment. Five patients (29%) required treatment breaks ranging from 8 to 16 days (median, 12 days) due to pancytopenia. Actuarial overall survival and relapse-free survival at 3 years for the 17 patients who completed radiation was 69 and 47%, respectively, with follow-up ranging from 19 to 53 months (median: 24, mean: 27.6 months). Seven patients (41%) relapsed within the abdomen alone and 2 patients developed extraabdominal lymph node metastasis as their sole site of failure. The prognostic factors evaluated for correlation with relapse-free survival included histologic subtype, grade, amount of residual disease at the time of surgery, and nodal involvement; only residual tumor at surgery (none vs ⩽2 cm or >2 cm) was found to be statistically significant ( P 2 cm residual disease, respectively. Radiation treatment was well tolerated, with only one patient developing treatment-related bowel obstruction 7 months after radiation therapy. The results of this planned trimodality treatment approach compare favorably with those reported following surgery and chemotherapy, particularly in patients who have been maximally cytoreduced.