CD4 and lymphoma: [7], [8] EATL type I shows frequent loss of surface T-cell receptor (TCR)αβ and nearly all cases express CD103, which is considered evidence of its origin from IELs, as this antigen is expressed by normal IELs. [7], [22] EATL type II comprises lymphomas of both the TCRαβ and TCRγδ lineages, with a subset of cases showing CD103 expression. [8], [23], [24] By contrast, all our lymphomas and all prior reported cases expressed CD4 and surface TCRαβ (or βF1) and all evaluated cases lacked CD103 and CD57 expression, consistent with a helper-inducer T-cell lineage.