670 Materials and methods Between August 2004 and November 2007, the medical records of all patients who underwent laparoscopic surgery for colorectal cancer were reviewed. Laparoscopic colorectal cancer resection was started August 2004 in our clinic. Pathologic confirmation, colonoscopy, barium enema, com- puted tomography (CT), ultrasonography, and chest PA were performed for diagnosis in all patients preoperatively. All patients with colorectal adenocarcinoma admitted to our clinic were considered for laparoscopic surgery. Exclusion criteria for laparoscopic surgery were as follows: (1) patients with colorectal cancer obstruction and failure of stent insertion, (2) patients with colorectal cancer perforation requiring emergency surgery, (3) patients with T4 colorectal cancer lesion that could not be resected laparoscopically, and (4) patients with compromised cardio-pulmonary function in whom pneumoperitoneum under general anesthesia was contraindicated. In this study, transverse colon cancer was defined as lesions between the hepatic flexure and splenic flexure in the colon, requiring ligation of the middle colic vessels at their origin. CT or barium enema was performed in all patients with colon cancer preoperatively for localization of the tumor. If radiological localization was unclear, preoperative colonoscopic Indian ink tattooing or endo- scopic clipping was performed. The procedure used for the transverse colon cancer was chosen based on the location of the tumor. A tumor located at the hepatic flexure or within 10 cm distal to hepatic flexure was treated by an extended right hemicolectomy, and a tumor located at the splenic flexure or within 10 cm proximal to the splenic flexure was treated by an extended left hemi- colectomy. A tumor located between the above two lesions was treated by a transverse colectomy. An extended right hemicolectomy was defined as lymphadenectomy simulta- neously with ligation of ileocolic, right colic, and middle colic vessels at their origins; an extended left hemicolectomy was defined as lymphadenectomy simultaneously with ligation of left colic and middle colic vessels at their origins. A transverse colectomy was defined as lymphadenectomy simultaneously with ligation of middle colic vessels at their origins. Extra-corporeal anastomosis was performed in all cases of laparoscopic surgery for transverse colon cancer. All patients started a diet after passing flatus. To evaluate the postoperative surgical outcomes and oncological quality of laparoscopic surgery for transverse colon cancer, we com- pare the age, gender, body mass index (BMI), operating time, blood loss, time to passing flatus, time to start of diet, hospital stay, surgical morbidity, surgical mortality, conver- sion to open surgery, tumor size, distal resection margin, proximal resection margin, radial margin, and number of harvested lymph nodes between the transverse colon cancer group (TCC) and other site colon cancer group (OSCC). In Int J Colorectal Dis (2008) 23:669–673 this study, a single surgeon (YS Lee) performed all operations. Comparisons between the two groups were made by applying the independent samples t test and χ2 test. Differences were considered to be significant for P value < 0.05. Results Postoperative clinical outcomes Three hundred and twelve patients underwent colorectal cancer resection in our clinic during these periods. Among them, 44 patients underwent conventional open surgery according to exclusion criteria (five cases of stent failure or colon obstruction, five cases of emergency operation, 12 cases of far advanced tumor, 12 cases of recurrent cancer operation, seven cases of patient’s refusal, and three cases for old age with high risk for pneumoperitoneum). There was no transverse colon cancer in the conventional open surgery group. A total of 268 patients underwent laparo- scopic resection for colorectal cancer. Of the 268 patients, 140 patients who underwent laparoscopic resection for rectal cancer were excluded in this study. Finally, 128 patients who underwent laparoscopic resection for colon cancer were enrolled in this study. Of the 128 patients, 34 patients had transverse colon cancer, counting for 10.8% of total colorectal cancers, and 94 patients had other sites of colon cancer. In the TCC group, extended right hemi- colectomy was performed in 18 cases, transverse colectomy was performed in eight cases, and extended left hemi- colectomy was performed in eight cases. In the OSCC group, right hemicolectomy was performed in 38 cases, left hemicolectomy was performed in five cases, and anterior resection was performed in 51 cases. There were no statistical differences in age, gender distribution, BMI, operating time, intraoperative blood loss, time to flatus, time to start of diet, and hospital stay between patients with TCC and OSCC (Table 1). Four patients in the OSCC group had a major complication, one had colon injury, and two had anastomosis leak. A simple laparoscopic closure was performed in the case of colon injury, and two patients with anastomosis leak underwent re-operation. Minor complications that occurred in four cases in the OSCC group (one case of ileus, two cases of port site minor infection, and one case of urinary retention) and two cases in the TCC group (one case of ileus and one case of atelectasis) were treated successfully conservatively. One case among the TCC group and three cases in the OSCC group were converted to open surgery; all of these converted cases were due to tumor-related factors, T4 lesion, or huge tumor. There was no surgical mortality in this study.