Incidence of second neoplasia in patients with B-cell chronic lymphocytic leukemia treated with chlorambucil maintenance chemotherapy.

The aim of this retrospective study was to examine the impact of prolonged chlorambucil (CLB) therapy on the development of second neoplasia (SN) in 389 patients with B-CLL, comparing untreated cases with those receiving CLB as induction plus maintenance therapy. Fifty-nine SN cases were observed (15.1%) at a median follow-up of 79 months. SN occurrence was significantly related to Binet stage. No difference was detected between untreated and CLB treated cases neither in terms of SN incidence (12.2% vs 18.1%) nor in the median follow-up (81 vs 79.1 months). Moreover, SN free survival was not different between these two groups. Four out of 13 CLB treated patients (30.8%) developed s-MDS after a subsequent treatment with fludarabine plus cyclophosphamide (F + C). In conclusion, SN development is dependent on the length of follow-up rather than on therapy duration. F + C should be administered with caution after prolonged CLB therapy.