Classical Hodgkin lymphoma is associated with frequent gains of 17q.

The etiology of Hodgkin lymphoma (HL) is poorly understood, and studies of the genetics of this disease have been hampered by the scarcity of the Hodgkin and Reed-Sternberg (HRS) cells within tumors. To determine whether recurrent genomic imbalances are a feature of HL, CD30-positive HRS cells were laser-microdissected from 20 classical Hodgkin lymphomas (cHLs) and four HL-derived cells lines and subjected to analyses by comparative genomic hybridization. In primary tumors, the most frequently involved chromosomal gains were 17q (70%), 2p (40%), 12q (40%), 17p (40%), 22q (35%), 9p (30%), 14q (30%), and 16p (30%), with minimal overlapping regions at 17q21, 2p23-13, 12q24, 17p13, 22q13, 9p24-23, 14q32, 16p13.3, and 16p11.2. The most frequent losses involved 13q (35%), 6q (30%), 11q (25%), and 4q (25%), with corresponding minimal overlapping regions at 13q21, 6q22, 11q22, and 4q32. Statistical analysis revealed significantly more gains of 2p and 14q in the older adult cases; loss of 13q was associated with a poor outcome. The results suggest that there is a set of recurrent chromosomal abnormalities associated with cHL and provide further evidence that cHL is genetically distinct from nodular lymphocyte predominance Hodgkin lymphoma (NLPHL). Abnormalities of 17q are infrequent in other lymphomas or NLPHL; this finding, coupled with current knowledge of gene expression in cHL, suggests that genes present on 17q may play an important role in the pathogenesis of cHL.