Survival analysis in treated plasmablastic lymphoma patients: a population-based study.

Herein we analyzed survival outcomes in chemotherapy-treated patients with plasmablastic lymphoma (PBL) diagnosed between 2010 to 2016 (n = 248). Data was acquired from the Surveillance, Epidemiology, and End Results (SEER) 18 registries database (April 2019 release based on November 2018 submission). The majority of patients were male (81.9%) and younger than 60 years (71.0%). Oral and gastrointestinal (GI) sites were the most frequent primary extranodal locations (23% and 19.4%, respectively). Oral primary location was inversely associated with presence of B symptoms and advanced Ann-Arbor stage. The 3-year and 5-year overall survival (OS) rates of treated PBL patients were 54% (95% CI: 46.5%-60.8%) and 52.8% (95% CI: 45.2%-59.8%). Three-year conditional survival for 2-year and 3-year survivors were 90.3% and 97.8%, overlapping the survival of a general population matched by age, sex and calendar year. In a multivariable analysis, oral primary location was associated with not only better OS (HR 0.43; 95% CI: 0.21-0.88, P = .021) but also better lymphoma-specific survival (LSS) (SHR 0.36; 95% CI: 0.15-0.86, P = .022); age ≥60 years was associated with shorter LSS (SHR 1.73; 95% CI: 1.02-2.96, P = .043). Seven registries granted access to HIV status (n = 93) where HIV infection was detected in 52.7% of cases. The HIV status did not affect survival outcomes in unadjusted and adjusted analyses. We identified clinical characteristics associated with survival and showed that treated PBL patients may achieve long-term survival.