Primary cutaneous T-cell lymphomas: a short, updated review (Part I)

Primary cutaneous lymphomas (PCL) are neoplasms of the immune system, characterized by a proliferation of either T or B lymphocytes or rarely plasmocytoid dendritic cells that primary arise in the skin, without extracutaneous manifestation of the disease at presentation. In 2005 a joint WHO-EORTC classification for primary cutaneouslymphomas has been published. This classification has been absorbed with few modifications into the new WHO classification of tumors of hematopoietic and lymphoid tissues published in 2008. Concerning cutaneous T-cell lymhoma (CTCL), mycosis fungoides remains by far the most frequent CTCL while Se´zary syndrome is rare and is still considered as the leukemic variant of CTCL. In the new classification cutaneous adult T-cell leukemia/lymphoma has been introduced; lymphomatoid papulosis is now considered a low-grade cutaneous lymphoma; subcutaneous panniculitis-like T-cell lymphoma has been included as distinct entity; and the category of primary cutaneous peripheral T-cell lymphoma, NOS includes 3 provisional entities (primary cutaneous aggressive epidermotropic CD8+ cytotoxic T-cell lymphoma, primary cutaneous c/d T-cell lymphoma, primary cutaneous CD4+ small-medium pleomorphic T-cell lymphoma).