The objective of this investigation was to determine the long-term survival and cost of treatment in patients with Stage IIIC epithelial ovarian cancer. Response to therapy, overall survival, and cost of treatment were analyzed in 100 patients with surgically staged IIIC epithelial ovarian cancer treated initially by tumor debulking, and at least 6 cycles of intravenous platinum/paclitaxel chemotherapy. Residual disease after surgical cytoreduction was > 1 cm in 52 pts, 1-2 cm in 18 pts, and < 2 cm in 30 pts. Sixty-six patients had platinum-sensitive ovarian cancers, and 34 had platinumresistant tumors. Chemotherapy response and patient survival were related to the volume of residual disease after surgical cytoreduction, and to platinum sensitivity of the tumor. Patient survival was 66% at 2 years and 30% at 5 years, but only 9% of patients were free of disease > 5 years after treatment. The average cost of treatment was $211,940 per patient and included hospital charges: $127,365 (60%), pharmacy charges: $57,597 (27%), and physician charges: $26,978 (13%). In conclusion, aggressive surgical debulking followed by platinum/paclitaxel chemotherapy is associated with increased survival of patients with Stage IIIC epithelial ovarian cancer. However, long-term disease-free survival ( < 5 years) is limited, and the financial cost of treatment is significant.