A rare case of sigmoid intussusception. A case report

Introduction and importance: Colorectal intussusception can be quite challenging to identify, especially its malignant nature. This is a fairly rare presentation and hence, there is not much associated research or cases reported in the literature. Case presentation: We present a 69 year old male with lower abdominal pain and a significant rectal prolapse. He has a background history of heavy smoking and significant alcohol intake. The prolapse was irreducible and had papillomatous changes present on the prolapsed mucosa. A computerized tomography (CT) scan demonstrated a large rectal prolapse followed by a Magnetic Resonance Imaging (MRI) Pelvis which showed an intussusception at the S2-3 level, consistent with a carcinoma, The patient then proceeded to have a flexible sigmoidoscopy with a planned proceed to an anterior resection. Histopathology revealed sigmoid and descending colon adenocarcinoma with mucinous differentiation pT3N0. He had an unremarkable hospital stay and remained well on follow up. His case was discussed at the multidisciplinary meeting and was not for any adjuvant chemotherapy. Clinical discussion: Imaging can help aid early diagnosis of a colorectal intussusception. Colonoscopies can be useful too; however these can be tricky to diagnose pre-operatively. If there is a high suspicion of malignancy, routine resection is the preferred method of treatment in cases of colorectal intussusception. Conclusion: Although not a very common presentation, diagnosis of colorectal cancer presenting as an intussusception can be dealt with imminently by considering operative measures.