Subcutaneous Panniculitis-Like T-Cell Lymphoma

**Semantic type:** Neoplastic Process

**Definition:** A cytotoxic primary cutaneous T-cell lymphoma. Recent studies suggest there are at least two groups of subcutaneous panniculitis-like T-cell lymphomas, each with distinct histologic features, immunophenotypic profile, and prognosis. One group has an alpha/beta, CD8 positive phenotype, involves only subcutaneous tissues, and usually has an indolent clinical course. The second group has a gamma/delta phenotype, is CD8 negative, often co-expresses CD56, is not confined to the subcutaneous tissues, and usually has a poor prognosis. In the recent WHO-EORTC classification, the term subcutaneous panniculitis-like T-cell lymphoma is reserved for cases with an alpha/beta, CD8 positive phenotype. Cases with a gamma/delta phenotype are included in the group of cutaneous gamma/delta T-cell lymphomas.

**Synonyms:** - SPTCL - Subcutaneous Panniculitis-Like T-Cell Lymphoma (Alpha/Beta Type) - Subcutaneous Panniculitis-Like T-Cell Lymphoma, Alpha/Beta Type - Subcutaneous panniculitis-like T-cell lymphoma - Subcutaneous panniculitis-like T-cell lymphoma