Clinical and Genomic Factors for Prognosis of AIDS Primary Effusion Lymphoma

Inclusion Criteria: * Patients diagnosed with primary effusion lymphoma (HIV seropositive or negative) on or after January 1, 1998 on whom survival status at 2 years post PEL diagnosis is available * Participants may be enrolled to either or both the clinical or genomic portions of the study * The minimum data required to be able to include a subject for analysis of clinical prognostic factors are: * HIV status, and for HIV subjects include cluster of differentiation (CD)4 count, HIV viral load closest to time of diagnosis * Age at PEL diagnosis * Gender * Stage at diagnosis * Treatment of PEL * Response to treatment * Survival status at 2 years * Pathology slides (or paraffin block) for central review * The minimum data required to be able to include a subject for analysis of genomic prognostic factors are: * Availability of a pathologic specimen of PEL that will be submitted for genomic analysis * Survival status at 2 years Exclusion Criteria: * Patients who do not fulfill the criteria as listed above are ineligible