Primary bilateral adrenal lymphoma masquerading as a metastatic melanoma: An unusual presentation of a rare disease

This report describes a 70-year-old male with bilateral primary adrenal lymphoma (PAL) characterized as non-germinal center diffuse large B-cell lymphoma (DLBCL). PAL is a very rare, aggressive disease with a poor prognosis. Our patient presented with B symptoms, chills, and nausea. Imaging studies of his abdomen revealed rapidly enlarging bilateral adrenal masses. Computed tomography (CT) guided left adrenal mass core biopsy showed diffuse sheets of neoplastic cells with irregular nuclear contours, vesicular to hyperchromatic chromatin, and prominent nucleoli. The neoplastic cells demonstrated an immunohistochemistry (IHC) profile consistent with DLBCL. Markers assessing for melanoma and neuroendocrine tumors were negative. Fluorescence in situ hybridization (FISH) revealed BCL6 rearrangement. The diagnosis of primary adrenal DLBCL, non-germinal center subtype, was rendered. The patient’s chemotherapy is ongoing; six cycles of R-CHOP chemotherapy (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) induced significant clinical and radiological response.

The differential diagnosis is broad in patients with adrenal insufficiency and bilateral adrenal masses, and our case clinically centered on metastatic melanoma in the differential. Thorough pathologic evaluation of tissue, including an extensive IHC panel, was warranted for this patient due to the rarity of PAL and due to the morphologic overlap between melanoma and DLBCL.