Phase II experience with ifosfamide/mesna in gynecologic malignancies: preliminary report of Gynecologic Oncology Group studies.

The Gynecologic Oncology Group initiated a series of phase II trials of ifosfamide/mesna in women with advanced or recurrent gynecologic malignancies in July 1985. Previously untreated patients received ifosfamide, 1.5 g/m2/d, intravenously (IV) for five days. Mesna was given IV in three doses every four hours after ifosfamide; each dose was 20% of the daily ifosfamide dose (ie, 300 mg/m2). All patients with ovarian and 87% of those with cervical cancer had undergone platinum-based therapy previously. Because of the toxicity encountered in previously treated ovarian cancer patients, the dose of ifosfamide was reduced to 1.2 g/m2/d in patients who had received prior chemotherapy or radiotherapy. In epithelial ovarian carcinoma, responses were observed in eight (21.6%) of 37 evaluable patients with three (8.1%) complete responses. Response duration was 2.1 to 20.3+ months with a median of 6.9+ months. In squamous carcinoma of the cervix, three (11.1%) of 27 evaluable patients had partial responses of 1.8, 2.2, and 3.1 months' duration. Of 29 untreated patients with mixed mesodermal tumors of the uterus, five (17.9%) had complete and four (14.3%) had partial responses for an overall response rate of 32.2%. Response duration was 1.4+ to 8.6 months with a median of 3.8 months. Toxicity included two deaths from renal insufficiency and a third related to neurologic impairment. Hematologic toxicity was manageable. Ifosfamide/mesna has activity in a wide range of gynecologic malignancies.