Treatment of extra-abdominal desmoid tumors with interferon-alpha with or without tretinoin

Background and Objectives: Surgery is the main treatment for extraabdominal desmoid tumors, but the results of further management remain uncertain. Th erefore, a retrospective analysis was undertaken to evaluate the toxicity a nd efficacy of treatment with interferon-alpha (IFN-alpha) +/- tretinoin in this setting. Methods: Thirteen patients with extra-abdominal desmoid tumors and a median age of 32 years (range, 15-73) received IFN-alpha. Seven of these patients received a combination of IFN-alpha and tretinoin in order to test further enhancement. Results: After a mean observation period of 27 +/- 15 months (mean +/- stan dard deviation) under treatment with IFN-alpha +/- tretinoin, local control was seen in 11 of 13 patients (85%). Seven patients had no evidence of dis ease at a mean disease-free interval of 22 +/- 18 months; in two patients p rogressive disease occurred after only 7 and 9 months, respectively, of obs ervation. In another four patients, progression of the desmoid tumor was st abilized. Conclusions: The data of this retrospective, nonrandomized study on therapy with IFN-alpha +/- tretinoin suggest that such treatment may be effective in prolonging the disease-free interval of patients after intralesional or marginal surgery. Because of the encouraging response rate, this regimen ap pears to be another nonsurgical treatment alternative. J. Surg. Oncol. 2000 :73:21-25. (C) 2000 Wiley-Liss, Inc.