Deoxycoformycin (pentostatin) in the treatment of splenic marginal zone lymphoma (SMZL) with or without villous lymphocytes

Background: Splenic marginal zone lymphoma (SMZL) is an infrequent B-cell neoplasm that pursues an indolent course. Signs and symptoms, mostly related to hypersplenism, are successfully managed by splenectomy. However, the therapy of patients who are not fit for a surgical procedure or who relapse after splenectomy, is still an unsettled issue. Patients and methods: We report a phase-II study on 16 patients with SMZL, three therapy naive and 13 pretreated, all showing systemic symptoms or progressive worsening of peripheral cytopenia, who were treated with pentostatin at a dose of 4 mg/m(2) every other week for 6-10 wk. In relapsed patients, the median interval between diagnosis and treatment was 26 month (range: 8-49). Results: Overall, 68% of the patients showed a clinical response. Two out three patients, who received pentostatin as first line therapy, attained a complete response (CR). One CR and seven minor or good haematological responses were recorded in relapsed patients. Treatment toxicity, mostly haematological, proved manageable. With a median follow-up of 35 month the median overall survival (OS) is 40 month and the median progression free survival (PFS) is 18 month. Conclusion: Our data show that pentostatin administered every other week has a good degree of activity in the treatment of SMZL and suggest that this schedule could be considered a possible therapeutic option for patients who are not fit for splenectomy or have relapsed.