Subcutaneous Panniculitis-Like T-Cell Lymphoma With Bone Marrow Involvement

Objectives: To describe a rare case of subcutaneous panniculitis-like T-cell lymphoma (SPTCL) with morphologic and immunophenotypic evidence of bone marrow involvement. Methods: Biopsy specimens of skin and subcutis and bone marrow were examined using H&E-stained sections. Immunohistochemical studies for CD2, CD3, CD4, CD5, CD7, CD8, CD20, CD30, CD56, and granzyme B were reviewed In addition, T-cell receptor gamma gene rearrangement studies were performed Results: A bone marrow core biopsy demonstrated several lymphohistiocytic aggregates containing atypical, cytotoxic T cells that rimmed adipocytes and were associated with karyorrhexis. These T cells were morphologically and immunophenotypically identical to a concurrent SPTCL, expressing CD2, CD3, CD7, CD8, and granzyme B but with diminished CD5 expression. Conclusions: SPTCL may rarely involve the bone marrow. Bone marrow infiltrates show a similar morphologic and immunophenotypic appearance to those in the subcutaneous fibroadipose tissue, including rimming of adipocytes by neoplastic lymphocytes.