Impact of the standardized medial-to-lateral approach on outcome of laparoscopic colorectal resection. is it a fair comparison?

We appreciate the interest of Day and Lau in our article titled “Impact of the standardized medial-to-lateral approach on outcome of laparoscopic colorectal resection” [1].. Day and Lau questioned whether the comparison of patients operated on by medial-to-lateral (medial) approach versus lateral-to medial (lateral) approach might have been biased by two factors: (1) Patients in the lateral approach group underwent operation earlier in time (January 2002–December 2003), when laparoscopic colectomy was a new procedure, surgeons were more cautious, and patients remained in the hospital longer after operation. (2) Differences in the results for the two groups of patients might be attributable to the use of different laparoscopic instruments.

In the Department of Surgery at Queen Mary Hospital, a program of laparoscopic colectomy was started in 1996, and the procedure has been widely applied since 2000. Prior to January 2002, more than 150 cases had been performed. Hence, laparoscopic colectomy was not a new procedure to surgeons in the unit during the period of patient inclusion for the lateral approach group. In the original article, we reported that when compared to the lateral approach group, patients in the medial approach group had an earlier return of bowel function as indicated by the reduced number of postoperative days to passing flatus (2(2–3) vs. (2(2–2) days, respectively; p < 0.001) and bowel motion (3(2–5) vs. (3(2–3), respectively; p < 0.001). Furthermore, because postoperative complications are uncommon and wound pain is minimal after laparoscopic colorectal surgery, patients are usually discharged after return of bowel function and tolerance of diet. We believe that earlier return of bowel function in the medial approach group was the key factor contributing to shorter hospital stays. We have also discussed the potential weaknesses of this comparative study, and we have reported that the same laparoscopic instruments, including the ultrasonic dissector, was used for both the medial and lateral approach groups.

Nevertheless, we concur with Day and Lau that standardization of the procedures is important in laparoscopic colectomy, which is a complex procedure with a steep learning curve. In the medial approach for laparoscopic colectomy, the procedure is divided into several standardized steps including proximal ligation of vascular pedicles, subsequent medial-to-lateral exploration of the retroperitoneum for identification and protection of important structures—e.g., duodenum, ureter—followed by mobilization and resection of bowel with anastomosis. We share the experience of other experts [2, 3] in that the that medial approach for laparoscopic colectomy constructs a more standardized operative technique. In the literature, only very few reports have compared the results of the lateral and medial approaches to laparoscopic colectomy. As Day and Lau’s surgical unit still performs both approaches, we encourage them to conduct a randomized trial for comparison of these two operative approaches in order to provide more evidence on this debate.