Survival of patients with marginal zone lymphoma: analysis of the Surveillance, Epidemiology, and End Results database.

BACKGROUND.: Prognostic factors and outcomes in patients with marginal zone lymphoma (MZL) have been studied in small cohort studies, which may not reflect the population at large. METHODS.: Clinical characteristics and survival outcomes of adult patients with MZL who were diagnosed between 1995 and 2009 were evaluated using the Surveillance, Epidemiology, and End Results (SEER) database. The authors generated clinical prognostic models for subtypes of MZL and compared survival during the periods of 1995 through 2000, 2001 through 2004, and 2005 through 2009. RESULTS.: The prognosis was significantly better for patients with mucosa-associated lymphoid tissue (MALT) lymphoma (5-year relative survival rate of 88.7%; P < .0001) compared with those with the splenic MZL (SMLZ)or nodal MZL (NMZL) subtypes (5-year relative survival rates of 79.7% and 76.5%, respectively). There was evidence of improved outcomes in patients with NMZL and MALT lymphomas between 1995 and 2009 (P < .0001), with no difference noted in patients with SMZL (P = .56). Advancing age and the presence of B symptoms had prognostic significance in all MZL subtypes. Male sex and stage of disease were significant only for the NMZL and MALT categories. Survival in patients with MALT lymphomas varied depending on the site of origin, with a worse prognosis noted in those with gastrointestinal and pulmonary locations of origin (5-year incidence rate of lymphoma-related death, 9.5%-14.3%) compared with ocular, cutaneous, and endocrine sites (4.5%-7.8%; P < .0001). CONCLUSIONS.: The survival for patients with SMZL is similar to that for those with NMZL, and unlike the NMZL and MALT subtypes, it has not improved over the past decade. The prognosis of patients with MALT lymphoma varies according to the anatomical site of origin.