Fig. 1

Preoperative examination of the patient. A Computed tomography (CT) revealed wall thickening from the upper rectum to sigmoid, accompanied by low intestinal obstruction (red arrow). B Magnetic resonance imaging (MRI) revealed neoplastic lesions of the sigmoid colon (white arrow). C Colonoscopy showed stenosing tumor formation in the upper rectum, the mucosal surface is smooth (green arrow). D After 7 days of colon decompression, computed tomography reexamination showed the dilatation of the colon was significantly less than before