A comparative study of intraperitoneal carboplatin versus intravenous carboplatin with intravenous cyclophosphamide in both arms as initial chemotherapy for stage III ovarian cancer

Cisplatin (C) or carboplatin (CBP) plus cyclophosphamide (CTX) was until re cently considered standard chemotherapy for advanced ovarian cancer (OC). A ttempts to maximize platinum and its analog activity against OC include its administration directly into the peritoneal cavity. In the past we have sh own that intraperitoneal (IP) CBP administration is a safe and effective tr eatment for OC [Polyzos et al: Proc Am Assoc Cancer Res 1990;31: 1120]. In the present study we aimed to compare the effectiveness and toxicity of CBP administration either intravenously (IV) or IP plus CTX IV. Since 1990, 90 evaluable patients with stage III OC were prospectively randomized to rece ive CBP 350 mg/m(2) IV or IP plus CTX 600 mg/m(2) IV (in both groups) every 3-4 weeks for six courses. The randomization incorporated stratification a ccording to performance status and the amount of residual tumor (maximum di ameter less than or equal to 2 or >2 cm). Clinical assessment was performed with abdominal CT and serum CA-125. Responses were observed in 33/46 = 72% (95/CI 56.5-84.0) of the IV group and in 33/44 = 75% (95/CI 59.7-86.8) of the IP group with 48 and 45% clinical complete responses, respectively. Tim es to progression were 19 months (8-62+) for the IV group and 18 (6-72+) fo r the IP group. Median survivals were: 25 months (6-80+) and 26 months (6-7 2+), respectively. Significantly more patients in the IV group than in the IP group had grade 3 or higher leukopenia (p < 0.01) and grade 3 thrombocyt openia (p < 0.09). Morbidity due to infectious complications in the IP grou p was minimal. It seems that IP CBP is equally effective to IV administrati on in terms of response and survival with less myelotoxicity. The favorable results on survival demonstrated in studies with IP C administration in pa tients with small volume disease [Alberts et al: N Engl J Med 1996;335:1950 -1965] could not be repeated in the present study applying CBP in patients with variable tumor size and a relatively small number of patients. The lik elihood that patients with large volume disease would benefit from a region al approach compared to systemic administration is small and this explains the inability to detect a difference between the two arms.