Treatment of splenic marginal zone lymphoma: should splenectomy be abandoned?

Splenic marginal zone lymphoma (SMZL) is a rare chronic B-cell lymphoproliferative disorder recognized as a distinct entity in the World Health Organization (WHO) classification. SMZL usually runs an indolent clinical course with a median survival of more than 10 years. However, in a proportion of patients (10-20%) SMZL behaves more aggressively, with a median survival of less than 4 years. Many efforts are ongoing to establish commonly accepted prognostic factors as a guide to therapy for this disorder. Data on the treatment of SMZL come from reported retrospective series including relatively limited numbers of patients. Despite these limitations, much progress has recently been made in the management of patients with SMZL. The oldest and most commonly used first-line therapeutic modality is splenectomy, which offers rapid alleviation of splenomegaly-related symptoms along with an improvement of cytopenias in the majority of patients, with a median PFS of 5 years. However, SMZL is a systemic disease, and splenectomy is not carried out with eradicative intent. Furthermore, splenectomy is a major surgical procedure with significant morbidity or even mortality, especially in older patients. Chemotherapy has only moderate activity in this form of MZL. Recent data suggest that rituximab is a very effective therapy with minimal toxicity and could replace splenectomy as first-line treatment. The overall response rate is > 90%, with almost half of responses being complete, while the 5-year progression-free survival is approximately 70%. The combination of rituximab with chemotherapy requires further evaluation. Based on the current data, splenectomy could be abandoned as first-line treatment for patients with SMZL.