Duration of response to second-line, platinum-based chemotherapy for ovarian cancer: implications for patient management and clinical trial design.

PURPOSE: Limited information is available regarding the influence of the duration of a prior response on the length of a subsequent response to platinum chemotherapy in recurrent ovarian cancer. PATIENTS AND METHODS: We retrospectively reviewed the medical records of women with ovarian cancer treated at the Cleveland Clinic from 1993 through April 2003 who received two or more platinum-based regimens for recurrence of the malignancy. Patients were considered to have responded to second-line therapy if they satisfied specific criteria, including favorable effects on both measurable or assessable disease.
RESULTS: A total of 211 platinum-based regimens were administered to 176 women with recurrent ovarian cancer during this time period, with a response being observed in 125 treatment episodes (59%). Only four (3%) of 121 currently assessable secondary responses were of longer duration than the prior response in a specific individual. In three of these four cases, the platinum-based regimen used in the second-line approach included a drug that had not been used in that patient's primary chemotherapy program.
CONCLUSION: The length of a prior response to platinum-based therapy in ovarian cancer is highly predictive of the upper limit of the duration of response to a subsequent platinum program, assuming the same or similar drugs are used. Knowledge of this clinical parameter may assist in developing optimal management for an individual patient and may potentially be exploited in clinical trial designs examining novel maintenance strategies with both cytotoxic and cytostatic agents in women who achieve a secondary response to a platinum-based regimen. Copyright 2004 American Society of Clinical Onocology