MONOCLONAL IGH GENE REARRANGEMENT IN MICRODISSECTED NODULES FROM NODULAR SCLEROSIS HODGKIN-DISEASE

Recently, single-cell PCR studies have demonstrated that Hodgkin and R eed-Sternberg (HRS) cells are clonally related in many cases of Hodgki n disease. To investigate the lineage and clonality of neoplastic cell s in local environments in nodular sclerosis Hodgkin disease (NSHD), w e microdissected multiple distinct nodules from patients with NSHD and analyzed them for IgH gene rearrangement by PCR. These results were c orrelated with immunophenotype, Epstein-Barr-encoded RNA (EBER) expres sion, and clinical outcome. Forty individual nodules from 10 patients with NSHD (11 specimens) were microdissected from formalin-fixed paraf fin-embedded tissue. DNA extracts were analyzed for IgH gene rearrange ment by using PCR with FRIIIa and JHa primers. Cases were immunophenot yped in paraffin sections with antibodies to CD20(L26), CD79a(HM57), C D45RO(A6), CD15 (Leu-MI), and CD30(Ber-H2). Infection of HRS cells by Epstein-Barr virus was evaluated by using EBER in situ hybridization ( EBER-ISH). DNA extracts from 12 of 40 microdissected nodules from 8 of 10 patients demonstrated a monoclonal pattern by IgH-PCR. Three patie nts demonstrated 2 individual nodules with different monoclonal patter ns. One patient demonstrated 2 nodules with bands that appeared simila r in size but were found to be different from one another upon further testing. All 28 remaining nodules demonstrated a polyclonal pattern. Six of 10 patients were positive for the Epstein-Barr virus genome by EBER-ISH. No correlation was found between IgH monoclonality, immunoph enotypic features, Epstein-Barr virus infection, or clinical outcome. It was concluded that a subset of NSHD cases contain detectable monocl onality within individual nodules by IgH-PCR, suggesting that HRS cell s are clonally related within local microenvironments.