Perianal Paget's disease: case report and review of the literature.

Cutaneous Paget's disease (PD) is a rare entity, predominantly involving the breasts. Anal involvement is rather exceptional, and can be associated with underlying malignancies, among which prostate and rectal adenocarcinoma. We report the case of a 71-year-old man suffering from a long history of anal itching, associated with an erythematosquamous lesion of the right buttock extending up to the anus. The diagnosis of perianal PD (PAPD) was confirmed by histopathological demonstration of Paget's cells from a biopsy performed after ineffective topical treatment. Radiological and further clinical inspections allowed us to exclude any synchronous malignancy. A first-step surgery consisted in coelioscopic diverting sigmoid colostomy, along with multiple perianal, anal and rectal biopsies revealing an anal canal involvement. Coelioscopic abdominoperineal surgery and a wide cutaneous excision were then performed. Histopathological analysis revealed positive posterior margin, requiring further excision. No adjuvant therapy was prescribed, and to this day, after a one-year and a half follow-up, the patient remains disease-free. Our case report and review of PAPD stress that appropriate management is required to improve the poor prognosis of this rare affection.