OBJECTIVE To evaluate the effect of platinum-based chemotherapy on tumor response in patients with advanced-stage serous ovarian carcinoma of low malignant potential. METHODS We conducted a retrospective review of hospital records, pathology slides, and office charts of patients identified as having Stage III or IV serous ovarian cancer of low malignant potential. RESULTS Between November 1979 and April 1993, 21 patients with advanced-stage serous ovarian carcinoma of low malignant potential received platinum-based chemotherapy following initial cytoreductive surgery. The amount of residual disease was recorded in 20 patients; 8 (40%) had macroscopic residual tumor < 2 cm in largest diameter, and 12 (60%) had only microscopic disease. Sixteen patients underwent a second-look laparotomy following chemotherapy; 10 (62.5%) had no evidence of disease, 1 (6%) had a partial response, 2 (12.5%) had stable disease, and 3 (19%) had progressive disease. During a mean follow-up of 64 months, only 1 patient had died of disease. She had progressive disease noted at second-look laparotomy. Five of 6 patients who did not have a complete response to initial chemotherapy underwent further therapy with oral etoposide (1), intraperitoneal platinum (2), intraperitoneal mitoxantrone (1), or both (1). The sixth patient received no further therapy. Three of the patients subsequently receiving salvage intraperitoneal therapy underwent a third-look laparotomy. Two had partial responses noted, while the third patient had stable disease. CONCLUSIONS Platinum-based chemotherapy is effective in achieving surgically documented responses in patients with advanced-stage serous ovarian tumors of low malignant potential. The benefit of this therapy in improving survival is unproven.