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 viral 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.

Relapse of hairy cell leukemia after 2-chlorodeoxyadenosine: long-term follow-up of the Northwestern University experience.

Although 2-chlorodeoxyadenosine (2-CdA) is effective in inducing complete remissions (CRs) in the majority of patients with hairy cell leukemia (HCL), neither the actual relapse rate, the clinical factors that may predict relapse, the long-term outcome, nor the response rate to re-treatment at relapse has been clearly determined. Fifty-two consecutive patients with previously untreated or treated HCL were treated with 2-CdA at a dose of 0.1 mg/kg/d by continuous intravenous infusion for 7 days. Of 50 assessable patients, 40 (80%) achieved CR, and 9 (18%) achieved partial remission (PR). A total of 7 patients (14%) have relapsed, at a median duration of 24 months (range, 12 to 44). Of the 7 relapsed patients, 5 were re-treated with a second cycle of 2-CdA; 2 achieved a second CR and 3 attained a PR. The progression-free survival (PFS) rate is 72% at 4 years for all 52 patients and 83% for patients achieving CR. The overall survival (OS) rate is 86% at 4 years. Only prior therapy was predictive of relapse. The majority of patients achieve durable CRs with a single cycle of 2-CdA. The relapse rate is low and the long-term prognosis is excellent. The few patients who relapse can attain second remissions after re-treatment with 2-CdA.

Cladribine in the treatment of relapsed or refractory chronic lymphocytic leukemia.

PURPOSE: Cladribine (2-CdA), a purine analog resistant to adenosine deaminase, has significant activity in a variety of lymphoproliferative diseases. This study was designed to determine the efficacy of 2-CdA in patients with relapsed or refractory chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: Twenty-six patients aged 40 to 88 years (median, 64) who either had relapsed after an initial response or were refractory to conventional chemotherapy with at least an alkylating agent were treated with 2-CdA 0.1 mg/kg/d by continuous intravenous infusion for either 5 or 7 days every 28 days for a maximum of six cycles. RESULTS: No complete remissions (CRs) occurred. Eight of 26 patients (31%) achieved a partial remission (PR). The actuarial median time to progression (TTF) in responding patients is 16 months (range, 6 to 22). The actuarial median survival duration of the responding patients is 12 months (range, 8 to 28). Eight of 26 patients (31%) sustained early toxicity. Seven of these eight patients died before the first reevaluation of infection (n = 3), pericardial tamponade (n = 1), Stevens-Johnson syndrome (n = 1), and stroke (n = 2). No nausea, emesis, alopecia, or renal, hepatic, or cardiac toxicity was observed. CONCLUSION: 2-CdA has activity in patients with relapsed or refractory CLL. However, patients who have received multiple prior regimens that included fludarabine are less likely to respond, and there can be significant morbidity. Treatment of patients with less prior therapy earlier in the natural history of the disease may lead to improved and more durable responses.