Abstract

Primary cutaneous CD4+ small/medium pleomorphic T-cell lymphoproliferative disorder is a rare subtype of cutaneous T-cell lymphoma characterized by abnormal CD4-positive T cells in the skin. It manifests as solitary or multiple red, pink, or violaceous skin lesions. PCSM-LPD is thought to be caused by genetic mutations or immune dysregulation, but its exact etiology is unknown. Diagnosis is achieved through clinical evaluation, skin biopsy, and immunohistochemical studies. Treatment approaches include topical therapies, phototherapy, and radiation therapy depending on the extent and aggressiveness of the disease. This report describes the case of an insignificant medical history 42-year-old male who presented to a dermatology clinic with a firm forehead nodule. There were no reports of an increase in size or other symptoms associated with the condition. Histopathological examination revealed pleomorphic lymphocytes mainly affecting the dermis in dense, nodular infiltrations. There was difficulty diagnosing the entity, as it overlapped with other lymphoproliferative disorders. Immunohistochemical staining was positive for CD3, CD4, CD5, and CD7. It was negative for CD10, CD21, CD30, EBER, and AE1/AE3 pancytokeratin. Further confirmation of the diagnosis was provided by the detection of a clonal rearrangement of the T-cell receptor beta TCRB. Further investigation indicated that no other organ was affected by the lesion. Over two years of follow-up, no recurrences or complications occurred after the initial excision. In conclusion, it is worthwhile to report this type of lymphoma, even though it is indolent. This is so that it may be considered in the differential diagnosis and for future research.