Multiple primary cutaneous plasmacytoma a decade after a nasal solitary extramedullary plasmacytoma: a puzzling case.

Primary cutaneous plasmacytoma should be in the differential diagnosis in case of solitary or multiple erythematous-violaceous nodules or papules. The diagnosis relies on clinical, histological, and immunochemical findings, without underlying evidence of multiple myeloma. Treatment should be individualized, and agents such as bortezomib or lenalidomide have shown to be effective.