Primary cutaneous T-cell-rich B-cell lymphoma: a case report and literature review

T-cell-rich B-cell lymphoma (TCRBCL) is a recently recognized B-cell lymphoma variant, characterized by a minor population of neoplastic B-cells existing in a background of predominant reactive T-lymphocytes. It is a rare entity, accounting for approximately 1 to 2% of all non-Hodgkin's lymphomas. It has both nodal and extranodal presentation. Primary cutaneous TCRBCL is an extremely rare lymphoma and only 16 cases have been documented thus far in the medical literature. We report the case of a 46- year-old man that presented with a slowly-growing, painless skin nodule on the left temporofrontal region of the scalp. A complete surgical excision was performed and histological examination revealed diffuse infiltration of the dermis by TCRBCL. A complete surgical excision of the skin lesion and systemic chemotherapy seems to have been effective because the patient is disease-free 2 years after the initial diagnosis was made. This study reports a very rare case of TCRBCL presented primarily in the skin. Because of its rarity, it is especially important to make the correct diagnosis using the appropriate immunohistochemical stains and apply the proper therapy.