Long term follow-up and late complications of 2-chlorodeoxyadenosine in previously treated, advanced, indolent non-Hodgkin's lymphoma

BACKGROUND. The aim of this study was to determine the long term outcome and toxicities after the administration of 2-chlorodeoxyadenosine (2-CdA) to patients with previously treated, advanced, indolent non-Hodgkin's lymphoma (NHL). METHODS. Twenty-two patients (median age, 55 years) with relapsed or refractory low grade NHL (median disease duration, 2.8 years) were treated with 2-CdA by continuous infusion at 0.1 mg/kg/day over 5 or 7 days every 28 days, for a maximum of 6 cycles. RESULTS. The overall response rate was 45%. Two patients (9%) achieved a complete response (CR), 8 patients (36%) achieved a partial response, and 12 patients (55%) had no response. The two patients achieving CR have remained in CR for 46 and 38 months, respectively. Freedom from treatment failure at 24 months was 32%. Overall survival at 24 months was 59%. Three patients developed second malignancies: acute myelogenous leukemia (AML), myelodysplastic syndrome, and a cutaneous lymphoproliferative disorder. Fourteen patients have died after a median follow-up of 28 months (range, 3.9-49.2 months) due to progressive NHL (11 patients), infection (2 patients), and AML (1 patient). CONCLUSIONS. 2-CdA is an active agent for patients with previously treated, advanced, indolent NHL and may result in lasting remissions. Late complications following treatment may include delayed bacterial, fungal, or vital infection. Determination of whether the second malignancies that occurred in three patients reported herein were related to treatment with 2-CdA will require further study.