LAUSR

PTCL-NOS: peripheral T-cell lymphoma, not otherwise specified INTRODUCTION T-cell lymphomas and leukemias are associated with a variety of dermatologic manifestations including pruritus, erythroderma, papules, patches, plaques, nodules, ulcers, hypopigmentation, alopecia, and slack skin. Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), is a non-Hodgkin lymphoma included in the World Health Organization classification of lymphoid neoplasms. The incidence in the United States is 0.4 cases per 100,000 and increasing. PTCL-NOS is a heterogeneous group of lymphomas caused by clonal proliferation of T cells with a mature phenotype that cannot be classified more specifically. Skin is the second most commonly involved site after lymph nodes. Approximately 20% of cases present in the skin, with or without concurrent systemic disease, termed systemic PTCL-NOS and primary cutaneous PTCL-NOS, respectively. The prognosis is poor.