Leukemic Variant of Mantle Cell Lymphoma: Clinical Presentation and Management

This review summarizes the unique presentation and management of the leukemic variant of mantle cell lymphoma (LV-MCL, also referred to as non-nodal MCL) and highlights the biologic and clinical differentiation from classical mantle cell lymphoma (cMCL) in biomarker expression, clinical features, prognosis, disease course, and treatment. Several studies have evaluated the gene expression profile of mantle cell lymphoma, differentiating LV-MCL from cMCL. The typical immunophenotypic profile is CD5-positive, SOX 11-negative, CD23-low, CD200-low, and cyclin D1 overexpressed. LV-MCL commonly has mutated immunoglobulin heavy chain variable region genes. Data on treatment of LV-MCL is limited to retrospective analyses; the ideal treatment for these patients is unknown although many have a clinically indolent, asymptomatic presentation and often may be observed for an extended period without active treatment. LV-MCL is a clinically and biologically distinct entity. Clinically, it must be distinguished from chronic lymphocytic leukemia and cMCL. Future prospective, randomized clinical trials are required to optimize management, define the initial treatment, and appropriately sequence treatment modalities.