A case of primary cutaneous peripheral T-cell lymphoma, not otherwise specified, with cytotoxic phenotype showing multiple ulcers on the entire body.

Primary cutaneous peripheral T-cell lymphoma, not otherwise specified (pcPTCL-NOS), is a rare, aggressive, fatal type of cutaneous T-cell lymphoma. The clinical presentation of pcPTCL-NOS is characterized by generalized plaques, nodules or tumors but ulcers are uncommon. We report an atypical case of pcPTCL-NOS with cytotoxic protein expression, presenting as multiple ulcers on the entire body. A 48-year-old man first presented with pruritic papules on the trunk. The papules gradually increased in number and became ulcerated. We finally diagnosed pcPTCL-NOS because of diffuse dermal infiltration of medium- to large-sized pleomorphic CD4 positive lymphoid cells. Ulceration suggests infiltration of lymphoid cells expressing cytotoxic proteins, which can induce apoptosis in the epidermis and dermis. Our patient died of bacterial sepsis that invaded from the uncontrollable ulcers. A suspicion of pcPTCL-NOS is needed when encountering clinical pictures of refractory multiple ulcers and a biopsy should always be performed, because treatment delay may lead to a very poor prognosis.