Long Term Results for Cladribine Induction and Interferon Maintenance Treatment in Previous Untreated Indolent Lymphoma.

Indolent lymphoma in advanced stage is an incurable disease. The main treatment goal is palliation with low treatment related toxicity. In a multicenter setting we prospectively treated 91 previous untreated indolent lymphomas with intravenous cladribine 0.12 mg/kg body weight for 4 or 5 consecutive days every 4 weeks for 4 cycles. Following the cladribine induction treatment an interferon-2c maintenance therapy was started until progression. Median age was 59 years (range 25–79). All patients had stage 3 or 4 disease. Overall remission rate was 70% with 23% complete remissions. We found no significant difference in remission rate between the 4 or 5 day regimen. The remission rate was not different between follicular lymphoma, mantel-cell lymphoma, or Waldenstrom’s disease. Neither did the international prognostic index influence the rate of remission. Median observation was 60 months for living patients. Median time to progression and survival was 22 and 69 months respectively. At 5 years 23% and 57% were progression free and alive respectively. Transformation in a high-grade lymphoma occurred in 11/91 patients. A secondary cancer was observed in 4/91 patients. Toxicity was mainly hematologic for cladribine. Interferon maintenance was poorly tolerated, 27% of patients did not complete the therapy. Four months of cladribine seems to have similar results as conventional therapy with chlorambucil for 6 to 12 months.