Immunoglobulin heavy chain gene (IgH) rearrangement was studied in a patient showing the occurrence of classical Hodgkin disease and large B-cell lymphoma (LBCL) in the same lymph node. The VHDHJH region was amplified by polymerase chain reaction, the template being the DNA extracted from single Hodgkin and Reed-Sternberg and LBCL cells, microdissected on hematoxylin-eosin–stained sections by laser capture. A repeated VH4DH3JH4 segment was found in Reed-Sternberg cells, whereas a repeated VH3DH3JH4 segment was observed in LBCL cells. Rearranged VH genes carried somatic mutations in both populations, indicating a common germinal center cell origin. The IgH rearrangement found in clonally related Reed-Sternberg cells differed from the one of LBCL cells in the VH region but showed the same JH and DH segments with no variation from the respective germline sequence. The DH–JH junction is the first immunoglobulin gene segment rearranged in precursor B cells. Because the possibility of secondary Ig gene rearrangement in peripheral lymphoid organs has recently been reported, in the patient described here Reed-Sternberg and LBCL cells might originate from a common precursor in which secondary VH replacement took place during the germinal center reaction, giving rise to two different clonally related lymphomas.
From the Institute of Pathologic Anatomy and Histopathology (C.B., S.L., A.V.L., N.P., T.T., L.L., P.T.) and the Institute of Hematology (M.Z., P.G.), University of Siena, Italy; Department of Cellular Science, Oxford University, UK (T.M.); Consiglio Nazionale delle Ricerche c/o I.O.R Bologna, Italy (C.C.); Service of Pathologic Anatomy and Hematopathology, Institute of Hematology “L. and A. Seràgnoli,” University of Bologna, Italy (S.A.P.).
Address correspondence and reprint requests to Prof. Lorenzo Leoncini, Istituto di Anatomia ed Istologia Patologica, Università degli Studi di Siena, Via delle Scotte, 6–53100 Siena, Italy (e-mail: email@example.com).
Supported by grants from A.I.R.C. (Milan) and M.U.R.S.T. (Rome).