Epidemiology and etiology of mantle cell lymphoma and other non-Hodgkin lymphoma subtypes

We aimed to give an overview of the descriptive epidemiology and etiology of mantle cell lymphoma (MCL) in the context of all non-Hodgkin lymphoma (NHL) and major NHL subtypes, based on available published reports. In retrospective case series, MCL cases represent between 2 and 10% of all NHL. Population-based studies of MCL incidence by basic demographic characteristics are limited to the past 15-20 years and to Europe and the US. In both regions, average incidence rates of approximately 0.5 cases per 100 000 person-years were reported, with a male-to-female ratio of 2.3-2.5:1, and a median age at diagnosis of close to 70 years. Some data suggest a possible increase in MCL incidence over the last two decades, but the observation may also reflect improved diagnostics. The causes of MCL are not known. Studies of potential risk factors of MCL are few and conducted primarily within the framework of all NHL. Moderate associations with MCL risk have been reported for Borrelia burgdorferi infection, family history of hematopoietic malignancies, and genetic variation in the interleukin-10 and tumor necrosis factor genes, but findings remain unconfirmed. Large multicenter studies are needed to address these and other factors in risk of MCL with sufficient statistical power in the future.