Imaging characteristics of computed tomography examination in colon cancer combined with obstruction

Objective To summarize the imaging characteristics and clinical diagnostic value of computed tomography (CT) examination in colon cancer combined with obstruction. Methods The clinical data of 33 patients with colon cancer combined with obstruction who were admitted to the Wuxi No.2 People's Hospital from June 2012 to March 2015 were retrospectively analyzed. All the patients received abdomianl plain scan and dualphase enhanced scan of CT, and the imaging data were summarized. Results Of 33 patients with colon cancer combined with obstruction, obstruction was located at the ascending colon in 9 patients, hepatic flexure of the colon in 2 patients, colon transverse in 7 patients, splenic flexure of the colon in 3 patients, descending colon in 3 patients, sigmoid colon in 7 patients and proctosigmoid in 2 patients. Thirty-three patients had irregular and thickened colonic wall at the obstructive segment and irregular constriction of colonic lumen, with a mean coloric wall thickness of 1. 9 cm (range, 0. 6-3. 2 cm) . The length of constriction was 2. 0-3.0 cm in 3 patients, 3.1– 4.0 cm in 3 patients, 4.1-5. 0 cm in 11 patients, 5.1-8. 0 cm in 12 patients and more than 8. 0 cm in 4 patients. The mean length, diameter and mean diameter of the constriction of 33 patients were 5.8 cm, 0-0.5 cm and 0.2 cm. The performance at the junction of the normal wall and the stenosis was scuff syndrome in 7 patients and shoulder symptoms in 5 patients. Colonic dilatation above the obstructive segment was detected in 26 patients with multiple gasfluid levels and in 7 patients with mainly gas. Twenty-nine patients had colonic dilatation at the proximal end of obstruction with the diameter of right colonic dilatation of 6.0 cm, diameter of left colonic dilatation of 4.0 cm and colonic collapse at the distal end of obstruction. Thirty-three patients had different grades of cecal dilatation with a mean diameter of 6.9 cm. Three patients had ischemic colitis including 1 patient with colonic perforation and free underarm gas. The serosal invasion or organ involvement of colon cancer was detected in 25 patients with unclear boundary and cable-strip or nodular opacities. Fourteen patients had lymph node metastases, with surrounding tumor or retroperitoneal heterogeneous enhancement, sacvariable necrosis area, short-tempered edge of lymph node, bar-type exudation surrounding some of lymph node. There was 3 patients with hepatic metastases and 1 with pulmonary metastasis. Conclusion Irregular and thickened colonic wall , irregular constriction of colonic lumen, scuff syndrome and shoulder symptoms at the junction of the normal wall, colonic dilatation above the obstructive segment and multiple gas-fluid levels are mainly characterics of CT examination for colon cancer combined with obstruction. Key words: Colonic neoplasms; Intestinal obstruction; Computed tomography, X-ray