Primary adrenal diffuse large B cell lymphoma: a clinicopathological and molecular study from China

Primary adrenal lymphoma is a rare entity that, in most cases, is derived from B cells. The most commonly seen primary adrenal lymphoma is diffuse large B cell lymphoma (DLBCL). To better understand the clinicopathological and molecular features of these tumors, we studied 14 Chinese patients with DLBCL who initially presented with an adrenal tumor. The clinicopathological features of the 14 primary adrenal DLBCL cases were retrospectively reviewed using immunohistochemistry, immunoglobulin gene rearrangement analysis, evaluation of Epstein-Barr virus status, and fluorescence in situ hybridization. Patient age ranged from 43 to 69 years, with a mean age of 58 years. The patients most commonly presented with abdominal pain and adrenal mass. Ten patients exhibited bilateral adrenal masses, and four had unilateral adrenal masses (three left, one right). Thirteen of 14 DLBCLs were DLBCL not otherwise specified, and one was an intravascular large B cell lymphoma. According to the algorithm of Hans et al. (Blood 103:275-282, 2004), 13 and 1 cases were classified as the non-germinal center B-cell-like subtype and the germinal center B-cell-like subtype, respectively. The Ki-67 index ranged from 35 to 80%. Epstein-Barr virus-encoded RNA was detected by in situ hybridization in 6 of the 12 available cases. Two patients showed BCL-6 rearrangements. The follow-up period ranged from 1 to 87 months. During the follow-up period, four patients died of the disease, five were alive with the disease, four were alive without disease, and one was lost during the follow-up period. In summary, most primary adrenal lymphomas are non-germinal-center B-cell-like subtype DLBCLs, which have high proliferative activity and a poor prognosis.