Cases of cutaneous and nasal CD56 (NCAM)-positive lymphoma in Japan have differences in immunohistology, genotype, and etiology.

CD56 (NCAM)-positive lymphoma frequently involves the skin and nasal area. This study shows it is likely that the clinicopathologic features of this lymphoma are distinctive to each of the primarily involved sites. Sixteen cutaneous and 11 nasal cases of CD56-positive lymphoma were examined. In 10 cutaneous cases, the lesions consisted of pleomorphic large-cell lymphoma that expressed CD3epsilon (CD3), CD2 (LFA2), CD4, CD122 (IL-2B receptor), TIA1, perforin, and granzyme B and displayed angiocentric/angiodestructive features. Lobular panniculitis was found in 8 of these cases, and 6 cases showed other organ involvement. The remaining 6 cutaneous cases consisted mostly of CD3epsilon- and CD4-positive, CD2-, CD122-, and TIA1-negative large blastic lymphoma, having less angiodestruction and panniculitis. Bone marrow invasion and leukemic changes were found in 4 of these cases during the clinical course. All 11 nasal cases showed pleomorphic small and medium-size lymphoma cells with angiodestructive features and were positive for CD3epsilon, CD2, CD122, TIA1, perforin, and granzyme B. CD4-positive lymphoma was found in 4 of these cases. Only 3 nasal cases showed other organ involvement. Genotypically, 2 of the 4 cases examined in the first cutaneous group, 3 of the 4 cases examined in the second cutaneous group, and only 1 of the 11 nasal cases showed rearrangement of the TcRCbeta gene by the Southern blot method. Only 2 cutaneous cases with panniculitis and all 11 nasal cases showed a positive nuclear signal for EBV-encoded RNA (EBERs) by in situ hybridization. Thus, two types of cutaneous CD56-positive lymphoma were found, each having a unique cell characteristic, genotype, and EBV infection pattern that differed from that of nasal-type lymphoma.