Cutaneous involvement as the first manifestation of T-lymphoblastic lymphoma and review of the literature.

Lymphoblastic lymphomas (LBLs) are uncommon malignant neoplasms derived from immature T- or B-lymphoid progenitor cells. Although cutaneous involvement may reach 33% in B-LBL, only 12 cutaneous cases of T-LBL have been published. We report the case of a 49-year-old woman with 2-month history of erythematous-violaceous plaques in the sternal region and breasts. Histopathologic examination showed a dense monomorphus infiltrate in dermis and positive immunostainings for CD3, CD99 and terminal deoxynucleotidyl transferase, thus indicating T-LBL. Staging work-up only revealed a mediastinal mass at diagnosis. After a 51-month follow-up and different treatment regimens, the patient remains alive although she has presented four relapses, all of them extramedullary.