Phase II trial of intraperitoneal mitoxantrone in the management of refractory ovarian cancer.

To define both the toxicity and efficacy of intraperitoneal mitoxantrone in the treatment of refractory ovarian carcinoma, 31 patients were entered onto a phase II trial of this agent delivered in a 2 L treatment volume on a monthly basis. Due to excessive local pain at the initial dose level (30 mg/m2), the amount of drug delivered with each treatment course was reduced to 20 mg/m2. Despite this reduction, 74% of patients required narcotic analgesia during treatment. In addition, there were four episodes of bowel obstruction (one requiring surgical intervention) during therapy, and two patients developed bowel obstruction and intraabdominal abscesses following the completion of treatment. Six of 18 evaluable patients (33%) whose largest tumor diameter was less than or equal to 1 cm at protocol initiation experienced surgically documented responses, compared with one of 11 patients (9%) whose largest tumor was greater than 1 cm in diameter. If the two patients exhibiting what we called a mixed response to treatment are included, seven of 21 patients previously treated with intraperitoneal cisplatin responded to this treatment program, including four patients who had failed to respond to intraperitoneal cisplatin. No responding patient has demonstrated clinical evidence of relapse with a median follow-up of 7 months (range, 3+ to 13+ months) from response laparotomy. Intraperitoneal mitoxantrone is an active treatment program in patients with small-volume refractory ovarian carcinoma, but local toxicity can be severe. Due to the toxicity encountered with this specific program, its use cannot be recommended for standard clinical practice. However, in view of the activity observed in refractory ovarian carcinoma, including responses in patients who had previously failed intraperitoneal cisplatin, it is important to continue to explore alternative therapeutic regimens using intraperitoneal mitoxantrone to reduce local toxicity while maintaining or improving efficacy.