Response to fludarabine in B-cell chronic lymphocytic leukemia patients previously treated with chlorambucil as up-front therapy and a CHOP-like regimen as second line therapy

Abstract

Background and objectives: Fludarabine (FAMP) is the most active single agent in relapsed and refractory patients with B-cell chronic lymphocytic leukemia (B-CLL). However, it is not clear whether it should be used immediatly after failure of chlorambucil (CLB). We addressed such an issue retrospectively analyzing a series of patients in whom FAMP was used as third-line therapy after a sequential use of CLB and CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) or CHOP-like regimen, respectively.

Design and methods: On a retrospective basis, 57 B-CLL patients fulfilling the above mentioned criteria and followed-up in seven different hematologic institutions, were evaluated.

Results: Of 57 patients who were evaluated for response, 3 (5.2%) achieved a complete response (CR), 30 (52.6%) had a partial response (PR) and the remaining 24 (42.1%) failed to respond to FAMP. Overall median survival from the start of FAMP therapy was 30 months. Survival by tumor response did not show any difference between responders and non-responders (p = 0.536). The survival was significantly shorter in the group of patients with progressive disease than in all other patients included in our study (p = 0.05). Using each patient as his own control (McNemar test) we attempted to evaluate the value of FAMP in inducing a therapeutic response after failure of previous therapies. Among the 37 patients resistant to CLB the response rate was 40.3% with FAMP (p = 0.037) and only 17.5% with CHOP (p = 1.0). Among 35 patients resistant to a CHOP-like regimen, the response rate was 29.8% (p = 0.066) after FAMP therapy.

Interpretation and conclusions: From our results, it seems that FAMP works better than a CHOP-like regimen in patients resistant to CLB although results do not translate into a survival advantage for responders.