INTRODUCTION: Our previous randomized clinical trial comparing the laparoscopic medial-to-lateral dissection with the more classic lateral-to-medial approach for resection of rectosigmoid cancer showed that the medial approach reduces the operative time and the postoperative proinflammatory response. Besides the oncologic advantages of an early vessel division and a "no-touch" dissection, we feel that the longer the lateral abdominal wall attachments of the colon are preserved, the better the exposure and the easier the dissection. Encouraged by the above-mentioned positive findings, we therefore further conduct this phase II clinical trial to examine the feasibility and surgical outcomes regarding the utilization of this medial-to-lateral laparoscopic dissection approach for the curative resection of right-sided colon cancer. METHODS: A total of 104 patients (from December 2000 to January, 2005) with advanced right-sided colon cancer (TNM stage II: n = 56; stage III: n = 48) requiring a curative right hemicolectomy were subjected to the laparoscopic medial-to-lateral approach that included initial exploration and ligation of ileocolic, right colic, and middle colic vessels in no-touch isolation fashion, subsequent medial-to-lateral extension of retroperitoneal dissection along Gerota fascia, opening of lesser sac by transection of gastrocolic ligament, and the final mobilization of hepatic flexure and lateral attachments of ascending colon (Fig. 1). This study was approved by the institutional review committee of National Taiwan University Hospital. The surgical details were shown in the video. Postoperatively, adjuvant chemotherapy with Mayo Clinic Regimen was given in patients with stage III diseases. The functional recovery and surgical outcomes were prospectively evaluated. RESULTS: The laparoscopic medial-to-lateral approach for a curative right hemicolectomy can be preformed with acceptable operation time (192.6 +/- 32.8 min, mean +/- standard deviation) and little blood loss (48.4 +/- 14.4 ml) through a small wound (6.0 +/- 0.8 cm). The number of dissected lymph node was 16.0 +/- 2.8. The operative complications represented 5.7% of all cases, including anastomotic leakage in two cases (1.9%) and wound infection in four cases (3.8%). The patients have quick functional recovery, as evaluated by the length of postoperative ileus (60.0 +/- 12.0 h), hospitalization (9.0 +/- 1.5 days) and degree of postoperative pain (4.0 +/- 0.5, visual analogue scale). Besides the expenses covered by the National Bureau of Health Insurance in Taiwan, the patient had to pay an extra-expenses of NT$ 25,000.0 +/- 2,800.0 (1.0 US$ = 32.0 NT$). During the follow-up periods (median: 30 months, range 6-55 months), recurrence of tumor developed in 6 (10.7%) of stage II and 10 (20.8%) of stage III patients, with liver metastasis in six patients, lung metastasis in 4, liver and lung metastasis in 1, intraperitoneal recurrence in 2, bone metastasis in 1, brain metastasis in 1, and port-site recurrence in 1. CONCLUSIONS: By medial-to-lateral dissection method, the laparoscopic right hemicolectomy can be performed with technical efficiency, short convalescence, and acceptable short-term oncologic results. We therefore encourage the use of this approach for patients requiring a curative laparoscopic right hemicolectomy.