OBJECTIVETo compare the difference of the diameters of superior mesenteric vein (SMV) and gastrocolic trunk (GCT) between patients with cecum-ascending colon cancer and normal individuals, and to assess the diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer.

METHODSPreoperative imaging data of 60 patients with primary cecum-ascending colon cancer confirmed by postoperative pathology at the First Affiliated Hospital of Sun Yat-sen University from June 2014 to December 2016 were retrospectively analyzed. The diameters of SMV and GCT were measured on preoperative CT images. SMV was measured at about 2 cm below the junction of SMV and splenic vein. GCT was measured at 1 cm near the proximal junction of right colon vein, right gastroepiploic vein and anterior pancreaticoduodenal vein. Another 60 people receiving pelvic CT examination without organ illness were collected as control. The diameter differences of SMV and GCT between cancer group and control group were compared. The diagnostic value of the diameters of SMV and GCT in cecum-ascending colon cancer was evaluated by receiver operating characteristic (ROC) curves.

RESULTSAmong 60 cases of cecum-ascending colon cancer, 36 were males and 24 were females with median age of 48 years (range 28-84); 13 were cecum cancer, 47 were ascending colon cancer; 11 had no lymph node and liver metastasis, 40 had lymph node metastasis, 9 had liver metastasis (all with lymph node metastasis). Compared to control group, the diameters of SMV and GCT in cancer group were significantly longer [SMV:(11.2±1.3) mm vs. (9.5±1.7) mm, t=6.04, P<0.001; GCT:(5.5±0.9) mm vs. (3.5±1.0) mm, t=11.51, P<0.001]. However, there were no statistically significant differences in diameters of SMV and GCT among hepatic metastasis, lymph node metastasis and no metastasis cancer groups (all P>0.05). The ROC curve analysis showed that the area under the curve of SMV diameter was 0.777, and the optimal cut-off point was 10.5 mm in the diagnosis of cecum-ascending colon cancer, with the sensitivity and specificity of 95.0%(57/60) and 46.7%(28/60) respectively. The area under the curve of GCT diameter was 0.923, and the optimal cut-off point was 4.5 mm in the diagnosis of cecum-ascending colon cancer, with sensitivity and specificity of 88.3%(53/60) and 85.0%(51/60) respectively.

CONCLUSIONThe dilation of the SMV and GCT may be used as warning factors for cecum-ascending colon cancer, especially the diameter of GCT.