Fibrin-associated large B-cell lymphoma arising in a cystic lymphangiomatous lesion of the adrenal gland: A case report and overview of the entity.

Fibrin-associated large B-cell lymphoma (FA-LBCL) has been recognized as a distinct entity in the 5th WHO classification of hematolymphoid tumors. It is a rare Epstein-Barr virus-positive B-cell neoplasia that arises in various sites of chronic fibrin deposition associated with (pseudo-)cystic cavities, chronic hematomas, cardiac myxomas, or prostheses. Cystic lymphangiomatous lesions of the adrenal gland are rare, benign vascular lesions that are most commonly asymptomatic. However, they are occasionally discovered incidentally and then often removed to rule out other, more serious diagnoses. The present case report documents a highly unusual instance of a 45-year-old female patient who was diagnosed with a FA-LBCL arising from a long-standing cystic lymphangiomatous lesion of the adrenal gland, representing a co-occurence of two rare diagnoses. We provide a comprehensive report of the morphological, immunohistochemical, and molecular features of this case of FA-LBCL and give a brief overview of this emerging lymphoma entity.