HTLV-1-negative pleomorphic T-cell lymphoma of the skin: the clinicopathological correlations and natural history of 15 patients.

The peripheral T-cell lymphomas represent a heterogeneous group and include, besides mycosis fungoides and Sézary syndrome, large-cell anaplastic lymphoma. We report 15 cases from our files that fulfil the histological criteria of pleomorphic T-cell lymphoma with primary skin involvement. Most of the cases were elderly with a male-to-female ratio of 1.5:1. The HTLV-1 serology was negative. The clinical features of these patients differed from those with mycosis fungoides and Sézary syndrome, in that eczematous and precursor lesions such as parapsoriasis en plaque were lacking apart from one exception. All the patients with small-cell pleomorphic T-cell lymphomas were alive, although three of the nine patients with medium-to-large tumour cells have died. Pleomorphic T-cell lymphoma should be regarded as a distinct entity among the lymphoproliferative disorders of the skin.