Anal neoplasia and perianal Crohn's disease: myth or reality?

The association between inflammatory bowel disease (IBD) and anal canal squamous cell carcinoma (SCC) has a low prevalence and is mainly supported by articles that include a series of cases. We describe the clinical, endoscopic and histological findings of a patient with Crohn's disease (CD) who developed SCC while undergoing biological therapy with active disease.