Rare Cutaneous Primary Presentation of Extracavitary Primary Effusion Lymphoma.

Primary effusion lymphoma (PEL) is a rare and aggressive B-cell lymphoma typically associated with human herpesvirus 8 (HHV-8) and Epstein-Barr virus infections. It classically presents as a malignant effusion in body cavities, but rarely presents with an extracavitary variant characterized by solid tumors in lymph nodes or extranodal sites such as the gastrointestinal tract, skin, lungs, and nervous system. This case report describes an unusual presentation of primary cutaneous extracavitary PEL in an HIV-positive patient that has only been reported in 8 cases previously.

Secondary skin involvement in classic Hodgkin lymphoma: Results of an international collaborative cutaneous lymphoma working group study of 25 patients.

Background: Cutaneous involvement by classic Hodgkin lymphoma (CHL) is an extraordinarily rare phenomenon in the current era. To date, no single large case series of cutaneous involvement by Hodgkin lymphoma has ever been reported in the literature.

Methods: A comprehensive search for cases designated "skin" and "Hodgkin" was performed at different institutions between 1990 and 2020.