Long-term results after consolidation radiotherapy on residual disease < 1 cm in 106 stage III ovarian cancer patients

Abstract

5039 Background: Attempts to increase survival of stage III ovarian cancer patients (pts), with macroscopic complete response at second-look laparotomy, have included prolonged chemotherapy, dose intensification, and consolidation radiotherapy. We present long term survival of 106 pts treated between 1983 and 1993 for stage III ovarian adenocarcinoma with first-look debulking, cisplatin-based chemotherapy, second-look surgery with a residual disease < 1 cm and consolidation radiotherapy. Method: Median age was 52 years (range 16–73). Residual disease after first look surgery was < 1 cm for 40,5 % of pts. Residual disease < 1 cm was obtained in all pts after second look surgery, with 33% of pts without residual disease. Radiation was performed using a linear accelerator. The whole abdomen dose was 22 Gy with antero-posterior fields and a maximal kidney dose of 20 Gy. 71 pts received a 25 Gy pelvic boost. 33 patients received an additional 12 Gy lombo-aortic boost. Results: Median follow-up was 14 years. Radiation was stopped for acute toxicity in 11 pts. Long term toxicities included radiation enteritis in 21 pts with 9 pts requiring surgery for bowel obstruction, radiation cystitis in 4 pts, acute leukemia in 2 pts, dysmyelopoiesis in 1 pt, skin cancers in the radiation field in 1 pt, bilateral femoral head necrosis in 1 pt. 4 pts died because of radiation complications. Second cancer was diagnosed in 12 pts with 7 breast adenocarcinomas, 3 colon adenocarcinoma, 1 non-small cell lung cancer, and 1 pancreatic cancer. Overall survival (OS) at 5 and 10 years was respectively 53% and 36 %. The main prognostic factor was residual disease after initial surgery, with a 10-year survival of 54 % with no or microscopic residual disease, 48 % with < 1 cm residual disease, 25 % with 1–2 cm residual disease. Conclusion: Long term survival of our patients compares favorably to those of similar patients treated in phase II studies with consolidation high-dose chemotherapy (5 year survival < 40%), at the price of high toxicity incidence (3,7 % of toxic deaths). No significant financial relationships to disclose.