Long-term results of the fludarabine, cyclophosphamide, and rituximab regimen as initial therapy of chronic lymphocytic leukemia.

Early results of the fludarabine, cyclophosphamide, and rituximab (FCR) regimen in 224 patients showed that it was highly active as initial therapy of chronic lymphocytic leukemia. In this report, we present the final results of all 300 study patients at a median follow up of 6 years. The overall response rate was 95%, with complete remission in 72%, nodular partial remission in 10%, partial remission due to cytopenia in 7%, and partial remission due to residual disease in 6%. Two patients (< 1%) died within 3 months of starting therapy. Six-year overall and failure-free survival were 77% and 51%, respectively. Median time to progression was 80 months. Pretreatment characteristics independently associated with inferior response were age 70 years or older, beta2-microglobulin twice the upper limit of normal (2N) or more, white cell count 150 x 10(9)/L or more, abnormal chromosome 17, and lactate dehydrogenase 2N or more. No pretreatment characteristic was independently associated with decreased complete remission duration. The risk of late infection was 10% and 4% for the first and second years of remission, respectively, and less than 1.5% per year for the third year onward. In a multivariate analysis of patients receiving fludarabine-based therapy at our center, FCR therapy emerged as the strongest independent determinant of survival.