CONCURRENT LYMPHOCYTE PREDOMINANCE HODGKINS-DISEASE AND T-CELL LYMPHOMA - A REPORT OF 3 CASES

Lymphocyte predominance Hodgkin's disease (LPHD) is a B-cell lymphopro liferative disorder; patients with LPHD have an increased risk of deve loping synchronous or metachronous B-cell non-Hodgkin's lymphoma. The synchronous presence of LPHD and B-cell lymphoma in the same lymph nod e in some cases lends support to the argument that the B-cell lymphoma arises as a consequence of transformation or progression of LPHD. We have recently identified three cases of LPHD occurring simultaneously with T-cell lymphoma in a series of 76 cases of LPHD in the files of t he Nebraska Lymphoma Study Group Registry. In large areas of the lymph nodes, atypical T cells with large, irregular, and hyperchromatic nuc lei were admired with Reed-Sternberg variants characteristic of LPHD ( L&H cells). However, in all cases, areas of typical nodular LPHD witho ut obvious T-cell lymphoma were also evident. In one case, frozen-sect ion immunohistochemistry demonstrated the absence of expression of CD5 , CD4, or CD8 by the T-cell lymphoma. The L&H cells in all cases expre ssed CD45 and CD20, as expected. In all three cases, clonal T-cell rec eptor (TCR)-gamma gene and TCR-beta gene rearrangements were documente d by polymerase chain reaction analysis and Southern blotting, respect ively. No clonally rearranged immunoglobulin genes were detected by ei ther technique. To our knowledge, this represents the first report of the simultaneous occurrence of LPHD and T-cell lymphoma. Although B-ce ll lymphoma occurring in the setting of LPHD is a well-recognized phen omenon, previous reports of T-cell lymphoma occurring after a diagnosi s of LPHD, as well as our cases with synchronous disease, suggest that the association of T-cell lymphoma and LPHD may not be uncommon as we ll. Furthermore, our cases indicate that T-cell lymphoma occurring in LPHD is not therapy related. However, the underlying mechanisms by whi ch these composite lymphomas occur remain unknown.