Desmoid tumours mimicking abdominal wall recurrence following rectal cancer resection

Colorectal cancer (CRC) recurrence found in the abdominal wall is a rare but devastating event following colorectal adenocarcinoma resection. Desmoid tumours (DTs) are benign, locally invasive tumours which can present clinically and radiologically similar to CRC recurrence in the abdominal wall. Although they have a superior prognosis, they have the potential for significant morbidity. This poses both a diagnostic and treatment dilemma requiring thorough investigation through imaging, histology and multidisciplinary discussion to optimise patient outcomes. We report two cases which involve the identification of abdominal wall masses highly suspicious for recurrence during routine surveillance in the period post-CRC resection. In the first case, the mass was excised, but surveillance was deemed appropriate in the second case following core biopsy. Histology confirmed DTs in both cases. Differentiating between abdominal wall recurrence and DTs represents a significant diagnostic challenge and a dilemma in regard to the decision to resect or not.