Cutaneous Plasmacytoma Associated with Squamous Cell Carcinoma of the Sacro-Coccygeal Region

We describe the case of a patient who received the diagnosis of squamous cell carcinoma of the radio-treated skin of the sacrococcygeal region where an extramedullary plasmacytoma had been identified one year before. We think that the plasmacytoma was born by a malignant transformation of a host-inflammatory reaction to a not-detected epithelial tumor. It can also hypothesized that plasma-cell dyscrasia or post-radiation infiammatory reaction had promoved the squamous cell carcinoma occurrence.