Interferon and low dose methotrexate improve outcome in refractory mycosis fungoides/Sézary syndrome

Treatment of refractory mycosis fungoides and Sézary syndrome remain unsatisfactory. In this study, we assessed the efficacy and toxicity of low-dose methotrexate (10 mg/m(2), biweekly) and interferon (9.0 MU, three times a week) as induction therapy by 6 or 12 months, followed, if patients achieved a complete remission, by interferon maintenance until toxicity or relapse. In an intent-to-treat analysis, 158 patients were considered evaluable. Complete response (biopsy proven) was observed in 112 patients (49 [31%] at 6 months and 63 [49%] at 12 months); thus, the complete response rate was 74%. With a median follow-up of 155 months (range, 62-181), progression-free disease was 71% and overall survival was 69%. Acute toxicity was mild, treatment was well tolerated, and to date no late toxicity has been observed. We conclude that this regimen is a benefit to this setting of patients, with excellent outcome and mild toxicity.