Laparo-endoscopic Single Site Cholecystectomy Versus Standard Laparoscopic Cholecystectomy

The aim of this study is to assess possible differences between the LESS approach and the standard laparoscopic approach to cholecystectomy. In particular, the Postoperative Quality of Life (QoL) will be investigated by analyzing the followings: length of hospital stay (LoS), postoperative pain, cosmetics and the results of SF 36 questionnaire. Furthermore, operative time, conversion to standard LC rate, difficulty of exposure, difficulty of dissection, and complication rate will be compared.

Altman nomograms were used to calculate the presumed sample size of an actual RCT, arbitrarily assuming a most likely small standardized difference (0.3). With a significant criterion set at 0.05, using a two-tailed test, the number of patients per group, required to have a 90% power is ~500. Therefore, it was decided to carry on a pilot trial, enrolling 40 patients (20 each group), to assess differences in any of the end-points and tailoring the sample size of the larger multicenter RCT accordingly.

This dual-institutional prospective, randomized pilot trial was conducted during 2009 obtaining information on the power and sample size needed for a planned multicenter randomized control trial. Our results showed that Quality of life data concerning LESS cholecystectomy are somewhat controversial: cosmetics and SF36 role emotional parameter significantly improved, no differences were found in length of hospital stay, early postoperative pain (same day of surgery) was higher but no impact on need for pain-relieving medications was found. Altman nomograms were used again to calculate the presumed sample size of an actual RCT based on the differences found on our initial results. With a significant criterion set at 0.05, using a two-tailed test, the number of patients per group, required to have a 90% power in this multicenter RCT is ~180 patients.

Study design Randomization is performed preoperatively and stratification is performed intraoperatively, after visualization of the operative field. Patients are randomized to one of three groups: LESS cholecystectomy blind, standard LC, LESS cholecystectomy not blind. Patients are stratified into 3 groups: Nassar grade I, II, III, according to the grade of difficulty of cholecystectomy (Nassar score) assessed at the initial inspection of the operating field.

Patients of the first two groups do not know the treatment received until their discharge. A large drape is used to cover the abdomen after surgery, thus hiding the surgical wounds. Patients of the LESS cholecystectomy not blind group are aware of the procedure they undergo. The third arm is intended to better evaluate the influence of psychological factors on postoperative pain, cosmetics and quality of life.