Malignant lymphoma of the adrenal gland: its possible correlation with the Epstein-Barr virus

Initial manifestation of malignant lymphoma in the adrenal gland is a rare event, and clinical and pathologic features are not fully understood. We conducted a nationwide study in Japan, and 20 patients with malignant lymphoma that showed initial and main manifestation in the adrenal gland were identified. Clinical and pathologic findings were summarized. In addition, the presence of the Epstein-Barr virus (EBV) genome in the tumor cells was examined by using polymerase chain reaction (PCR) and in situ hybridization (ISH), together with the immunohistochemical evaluation of the expression of latent membrane protein-1 (LMP-1). There were 13 men and seven women; their ages at admission ranged from 40 to 87 years (median, 65 yr). Fever, anemia, and elevation of lactic dehydrogenase levels were the common presenting findings. One patient had acquired immunodeficiency syndrome. Adrenal tumors were bilateral in 15 patients and unilateral (all in the left site) in five. Prognosis was very poor; all but two patients died within 1 year after admission. Histologically diffuse large cell type was the commonest type (14 specimens). Immunohistologically, 16 specimens were B-cell type, and one was T-cell type. Another three specimens showing no positive reaction for any antibodies were also judged as B-cell type on purely morphologic grounds. Prominent intravascular proliferation of tumor cells was found in five patients. PCR for EBV genomes gave positive results in five patients; the virus was subtyped as A in three patients and as B in two. The ISH provided positive signals in nine samples, including all five specimens positive for PCR. Four of the nine cases with detectable EBV by PCR and/or ISH expressed LMP-1. The present study shows that adrenal lymphoma is EBV associated and has a B-cell phenotype.