Lacy AM, Garcia-Valdecasas JC, Delgado S, et al: Laparoscopy-assisted colectomy versus open colectomy for treatment of non-metastatic colon cancer: a randomized trial. Lancet 359: 2224-2229, 2002
Leung KL, Kwok SPY, Lam SCW, et al: Laparoscopic resection of rectosigmoid carcinoma: prospective randomized trial. Lancet 363: 1187-1192, 2004
Nelson H, Sargent DJ, Wieand HS, et al: A comparison of laparoscopically assisted and open colectomy for colon cancer. N Engl J Med 350: 2050-2059, 2004