Cutaneous T-cell lymphomas

These are peripheral T-cell tumours, usually expressing CD4 along with other T-cell markers. The CD30 molecule is expressed in a histologically distinct subset (vide infra). Classification: The WHO identifies some well-defined clinicopathological entities with distinct clinical behaviour. Indolent forms include mycosis fungoides, primary cutaneous CD30 (Ki1) positive anaplastic large cell lymphomas and its benign variant lymphomatous papulosis; aggressive forms include Sezary's syndrome and peripheral CD30-negative T-cell lymphoma.