Long term survival with whole abdominopelvic irradiation (WAI) in platinum-refractory ovarian cancer

Purpose: To evaluate the efficacy and toxicity of WAI in persistent or recurrent epithelial ovarian carcinoma after initial chemotherapy. Methods and Materials: Between 1970 and 1995, 41 women with persistent or recurrent ovarian carcinoma after initial surgical debulking and chemotherapy were treated with WAI. Median age was 57 years (range 27-75). Initial FIGO stages were I and II - 5 patients (12%), III - 26 (64%), and IV - 10 (24%). Tumor grade was 1 - 4 (10%), II - 16 (39%), and III - 20 (49%). Four to eighteen (median eight) cycles of chemotherapy had been given prior to WAI. Thirty-one patients had received platinum-based regimens, and 22 of these had failed within six 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 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 an open-field technique with appropriate liver and kidney shielding. Results: With follow-up of 1 month to 16.5 years, the 5-year actuarial disease specific survival was 47% in all 41 patients, and 49% in 22 platinum-refractory patients. Both disease bulk at WAI (p<10-4) and initial stage (p=0.005) were of prognostic value. Five-year disease specific survivals were stage I and II - 100%, stage III - 55%, and stage IV - 27%. Five-year disease specific survival of all nonbulky (less than 1.5 cm) patients was 40%; 0% for patients with disease greater than 1.5 cm. Five-year disease specific survival for grade I - 66%, II - 59%, and III - 33%. Stage I, II, or III patients with residual disease bulk of 1.5 cm or less before WAI had a 10-year actuarial disease specific survival of 50%. Twelve patients (29%) failed to complete the planned course of WAI due to acute toxicity (most often due to prolonged thrombocytopenia). Late bowel toxicity included obstruction in one patient and fistula in one patient. Conclusion: Whole abdominopelvic irradiation should be considered in selected patients who fail initial chemotherapy, especially patients with nonbulky platinum-refractory disease. With acceptable toxicity, WAI results appear to be significantly better than second-line chemotherapy