Diffuse large B cell lymphoma presenting as a peri-anal abscess.

A non-healing peri-anal abscess can be difficult to manage and is often attributed to chronic disease. This case documents a male in his seventh decade who presented with multiple peri-anal collections. The abscess cavity had caused necrosis of the internal sphincter muscles resulting in faecal incontinence. Biopsies were conclusive for diffuse large B-cell lymphoma. A de-functioning colostomy was performed and the patient was initiated on CHOP-R chemotherapy. Anal lymphoma masquerading as a peri-anal abscess is rare. A high degree of suspicion must be maintained for an anal abscess which does not resolve with conservative management.