Kubota T, et al. - In this systematic study, researchers investigated prognostic factors in patients with human herpes virus-8 (HHV-8)-negative effusion-based lymphoma (HHV-8-negative EBL). They analyzed clinical and pathologic characteristics of 67 cases of HHV-8-negative EBL, including 2 of their own cases, in this work. As per univariate analyses, significant favorable prognostic factors comprised older age (70 y and above), Japanese ethnicity, pericardial effusion, CD20 expression, and chemotherapy with rituximab. Age and CD20 expression were identified as independent prognostic factors in multivariate analysis. Peritoneal effusion was identified to be an unfavorable prognostic factor.