Cutaneous T cell lymphoma differing from classical mycosis fungoides and Sézary syndrome: clinical, histological and immunohistochemical studies of six cases.

Six cases of cutaneous T cell lymphoma (CTCL), differing from classical mycosis fungoides (MF) and Sézary syndrome (SS), were studied. Initial skin eruptions were erythematoplaques, papules and tumors. Some cases showed frequent spontaneous regressions without any specific therapy; however, the prognosis was not always good. Surface phenotypes of neoplastic cells were markedly heterogeneous from the onset of initial skin eruption. Three cases expressed the T helper/inducer (Th/i) phenotype, one case had both the Th/i and T suppressor/cytotoxic phenotypes, and the other two cases lacked both surface markers. These results suggest that CTCL other than MF and SS displays marked heterogeneous clinical behavior and diverse morphological and immunophenotypical characteristics of the postthymic T cells.