Phase II trial of intraperitoneal cisplatin and mitoxantrone in patients with persistent ovarian cancer

The aim of this study was to determine the feasibility and efficacy of intraperitoneal cisplatin and mitoxantrone in patients with very small-volume residual disease at second-look surgery after completion of primary platinum-based intravenous chemotherapy.

Between February 1992 and February 1994, 42 patients were treated with up to five cycles of intraperitoneal cisplatin (100 mg/m2)/mitoxantrone (10 mg/m2). Patients were evaluated for surgically defined response rate and followed for progression-free (PFS) and overall survival (OS) using an intention-to-treat analysis, and grouped according to disease volume at initiation of treatment.

The mean age of all patients was 48.5 years. Thirty patients (71%) were Stage III at diagnosis; 18 patients (43%) had microscopic disease at the initiation of IP therapy, and 24 patients (57%) had macroscopic disease. Twenty-eight patients completed three or more cycles of protocol therapy, and 14 patients were changed to standard intravenous therapy after receiving fewer than three cycles of treatment secondary to catheter-related problems (12 patients), cisplatin ototoxicity (1 patient), or withdrawal from study (1 patient). Using an intention-to-treat analysis, the median PFS was 22.5 months, and the median OS of all patients (N = 42) was 47 months (6-72 months) with a median follow-up of 62.7 months. When grouped according to size of disease at initiation of treatment, the OS has not been reached at 62.7 months of follow-up in patients (N = 18) with microscopic disease.

(1) The combination of IP mitoxantrone and cisplatin has an unacceptable catheter failure rate due to mitoxantrone toxicity; (2) PFS and OS is longer in patients with microscopic rather than macroscopic residual disease; and (3) intraperitoneal platinum-based chemotherapy in patients with very small-volume residual disease may result in improved survival.