Linfoma no Hodgkin anaplásico de células T primario cutáneo rico en neutrófilos y eosinófilos. Estudio inmunohistoquímico de una variante poco frecuente

Anaplastic large cell lymphoma (LACG) is a T-cell lymphoma of pleomorphic CD30-positive cells. According to the expression of the chimeric protein ALK, LACG can be divided into three groups: systemic LACG ALK-positive, systemic LACG ALK-negative, and primary cutaneous LACG ALK-negative. According to the new WHO/EORTC classification, primary cutaneous LACG is included in the cutaneous T-cell lymphoproliferative disorders. We report an infrequent variant of primary cutaneous LACG. A 54-year old man presented with a 5 cm mass in the skin of his right gluteus, which had been present for six months without systemic involvement. Histological findings revealed a diffuse dermal infiltration of large CD3, CD43, CD30-positive, ALK-negative T-cells. Mixed with the neoplastic cells, there was a profuse infiltrate of neutrophils and eosinophils, establishing the diagnosis of neutrophil and eosinophil-rich primary cutaneous LACG. The presence of an increased number of neutrophils and/or eosinophils without necrosis, ulceration or infection is a rare finding in lymphomas, even more rare is the location in the skin of which only 16 cases have been reported in the literature. It is important to be aware of these findings in the differential diagnosis with other reactive or neoplastic entities that are more often accompanied by mixed inflammatory infiltrate, and with a different prognosis and treatment.© Dermatología Revista Mexicana