Unusual presentation of an uncommon abdominal pathology.

Desmoid tumour is a non-encapsulated locally invasive tumour, originating from fibroblasts, which has ubiquitous distribution in the body. It has a high tendency for local recurrence, causing deformity in the adjacent organ and consequent organ dysfunction. A case of a 75-year-old man, presenting with high-grade fever, dull aching abdominal pain and weight loss, suspected to be due to malignancy, is reported. Contrast-enhanced computed tomography (CECT) showed a mass in the transverse colon with pericolic collection raising a suspicion of perforation. He underwent a two-stage procedure in the form of defunctioning ileostomy in the initial setting followed by colonic resection and anastomosis 6 weeks later. Histological analysis revealed mesenteric fibromatosis (desmoid tumour). The patient was completely asymptomatic one year after surgery. We report this case, as our patient had none of the predisposing factors. To the best of our knowledge, this is the first case on colonic perforation secondary to desmoid tumour.