Ifosfamide and vinorelbine in advanced platinum-resistant ovarian cancer: excessive toxicity with a potentially active regimen.

OBJECTIVES

The aim of this study was to determine the activity and toxicity of a vinorelbine and ifosfamide combination in platinum-resistant advanced ovarian cancer.

PATIENTS AND METHODS

Patients were treated with ifosfamide (2 g/m(2)/day) infused over 1 h x 3 days (with mesna uroprotection) and vinorelbine (30 mg/m(2)) on days 1 and 8. Treatment was repeated on a 21-day schedule. In order to avoid unacceptable toxicity in this subset of patients where the chemotherapy is mainly palliative, the Bryant and Day two-stage phase II trial design incorporating toxicity considerations was chosen. A cutoff point for the response rate (10%) and for severe toxicity (25%) was established for the first 14 patients.

RESULTS

Between February 1997 and December 1998, 11 paclitaxel and platinum-resistant patients and 1 potentially platinum-sensitive patient were treated. Five patients (41%) experienced grade 3-4 central nervous toxicity requiring hospital admission. In accordance with the Bryant and Day design, the study was stopped early because greater than 25% of the first 14 patients developed grade 3-4 neurotoxicity. A retrospective review of clinical characteristics of these patients showed at least one well-known risk factor associated with ifosfamide central toxicity. Hematological toxicity was common, mainly grade 4 neutropenia, which was observed in all but 1 patient, usually of short duration, and there were 4 episodes of neutropenic fever. Ten patients were evaluated for response. Two complete responses and 1 partial response according to CA-125 criteria were observed.

CONCLUSION

This combination may be active in platinum-resistant ovarian cancer but the high toxicity encountered, principally neurotoxicity in those with large central pelvic masses, means that further studies with this schedule may not be warranted.