Benign Yet Deceptive A 19 Year Old Male with Rectal Mass Mimicking Carcinoma Ultimately Diagnosed as Colitis Cystica Profunda

Colitis cystica profunda is a benign condition that may closely mimic advanced rectal carcinoma on both endoscopic and radiologic evaluation, leading to significant diagnostic confusion.Persistent discordance between imaging and histology warrants deeper biopsies and multidisciplinary team review before considering radical intervention.In young adults presenting with rectal masses, clinicians must consider both malignant (e.g., adenocarcinoma, lymphoma) and rare benign entities such as colitis cystica profunda. Careful pathology review, correlation with imaging, and genetic counselling when appropriate are essential.