Primary Cutaneous Diffuse Large B-Cell Lymphoma With a MYC-IGH Rearrangement and Gain of BCL2: Expanding the Spectrum of MYC/BCL2 Double-Hit Lymphomas.

Aggressive extracutaneous B-cell lymphomas span the various stages of B-cell ontogeny and include B-cell lymphoblastic lymphoma, Burkitt lymphoma, mantle cell lymphoma, and diffuse large B-cell lymphoma. Diffuse large B-cell lymphomas represent the most common histologic subtype of non-Hodgkin lymphomas, comprising 30% of adult non-Hodgkin lymphomas in the United States. A distinctive form of diffuse large B-cell lymphoma is the double-hit lymphoma, with most cases exhibiting a combined MYC and BCL2 rearrangement, leading some hematopathologists to propose the term MYC/BCL2 lymphoma. More recently, MYC rearrangement with multiple copies/gain of BCL2 or multiple copies/gain of MYC with a BCL2 rearrangement have been described and exhibit a very similar clinical course to conventional double-hit lymphomas. We report the seventh case of diffuse large B-cell lymphoma exhibiting this distinct cytogenetic abnormality and the first reported case in the skin. The patient's clinical course was aggressive, succumbing to disease 18 months after his initial presentation.