Long-term survival with whole abdominopelvic irradiation in platinum- refractory persistent or recurrent ovarian cancer

Abstract

The purpose of this study is to retrospectively evaluate the efficacy and toxicity of whole abdominopelvic irradiation (WAI) in patients with persistent or recurrent epithelial ovarian carcinoma who failed chemotherapy. Between 1970 and 1995, 41 women with persistent or recurrent ovarian carcinoma after initial treatment with surgical debulking and chemotherapy (4 to 18 cycles; median, 8) were treated with WAI. Thirty-one patients had received platinum-based regimens, and 22 of these had failed within 6 months after completion of chemotherapy ('platinum-refractory'). Prior to WAI, 11 (27%) patients had microscopic residual disease, 21 (51%) had gross residual disease up to 1.5 cm, and 9 (22%) had residual tumors greater than 1.5 cm in maximal diameter. Median doses of 28 Gy to the abdomen and 48 Gy to the pelvis were delivered using open-field techniques and liver and kidney shielding. With follow-up of 1 month to 16.5 years (median potential follow- up, 1.4 years), the 5-year actuarial disease-specific survival was 47% in all 41 patients, and 50% in the 22 platinum-refractory patients. Both residual tumor size at WAI (P < 10-4) and initial stage (P = 0.003) were of prognostic value. Five-year disease-specific survival of all patients with residual tumors less than 1.5 cm was 53%; 0% for patients with tumors greater than 1.5 cm. Five-year disease-specific survivals by initial stage were: stage I and II, 75%; stage III, 40%; and stage IV, 15%. Stage I, II, or III patients with residual disease up to 1.5 cm before WAI had a 10-year actuarial disease-specific survival of 40%. Twelve patients (29%) failed to complete the planned course of WAI due to acute toxicity (most often due to prolonged thrombocytopenia). Late toxicity (requiring surgery) included bowel obstruction in two patients and fistula in one patient. Whole abdominopelvic irradiation should be considered in selected patients who fail initial chemotherapy, especially in patients who can or have been debulked to small amounts of residual disease. With acceptable toxicity, WAI results appear to be as good as or better than second-line chemotherapy, particularly in platinum-refractory patients.