T-cell lymphoblastic lymphoma (T-LBL) is an aggressive, rare neoplasm of immature T-cell precursors, typically presenting with lymphadenopathy, a mediastinal mass, and bone marrow involvement. We report the case of a 25-year-old man who presented with plaques and subcutaneous nodules on the scalp, forehead, and left cheek, accompanied by posterior cervical lymphadenopathy. Immunohistochemical studies of intralesional punch, lymph node, and bone marrow biopsies confirmed a diagnosis of T-LBL. In addition, NOTCH1 oncogene mutations, a common feature of T-LBL, were detected. Although cutaneous involvement in T-LBL is rare and uncommonly the most prominent symptom, this case highlights a rare presentation with predominantly cutaneous manifestations. This emphasizes the importance of early recognition when malignancy is suspected to prevent the development of more severe complications.
Keywords: T-cell lymphoblastic lymphoma; cutaneous T-LBL; lymphadenopathy; mediastinal mass.
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