Mycosis fungoides--type cutaneous T-cell lymphoma arising before 30 years of age. Immunophenotypic, immunogenotypic and clinicopathologic analysis of nine cases.

Abstract

Cutaneous T-cell lymphomas (CTCLs) rarely arise before 30 years of age; therefore the characteristics of these lymphomas are largely unknown. Our purpose was to assess the clinical and pathologic aspects of CTCL in young persons. We identified nine patients who had epidermotropic CTCL by 30 years of age and analyzed their lymphoma phenotypes and genotypes. The diagnosis of CTCL was made an average of 6 years after the reported onset of the lesion. Histologic examination revealed the mycosis fungoides (MF) form of CTCL, and none of the patients underwent conversion to nonepidermotropic or large-cell variants of CTCL. The immunophenotypes were typical of MF-type CTCL; seven of eight lymphomas tested were predominantly CD4+ although in only three were abnormal CD4/CD8 ratios present. All four cases tested were CD7- (Leu-9-), and seven of eight specimens tested exhibited deficient Leu-8 expression. The loss of one or more pan-T-cell markers was found in four of eight patients tested. Clonal beta-chain T-cell receptor gene rearrangements occurred in skin samples from four of eight tested cases. A persistent eruption, even in youths and young adults, should be thoroughly evaluated for possible CTCL.