Seventy percent of complete responders remain in continuous remission: Five-year follow-up of 300 patients treated with fludarabine, cyclophosphamide, and rituximab (FCR) as initial therapy of CLL

7008 Background: The early results of 224 CLL patients receiving the FCR regimen were previously reported (JCO 23:4079). Mature follow-up data (median 62 months for survivors) is now available for the complete cohort of 300 patients. Methods: Eligible patients were =16 years old with previously untreated CLL requiring therapy. Median age was 57 years (31%=60 years, 14% =70 years), and 61% & 36% were in modified Rai intermediate & high risk categories respectively. Prognostic factors: B2m >2x normal 42% (n=295), CD38 positive 28% (n=253), abnormal metaphase cytogenetics 29% (n=221), IgVH unmutated 66% (n=94), ZAP-70 positive 49% (n=88). The planned six cycles of therapy were completed in 74% patients. Results: Responses were: 72% CR, 11% nodular PR (PRn) & 12% PR. On multivariate analysis, CR rates were inferior in patients with B2m >2N (p=0.001) and white cell count >150 × 109/L (p=0.01). Rai stage, CD38 positivity, IGVH mutational status and ZAP-70 positivity were not associated with inferior CR. Median ...