Commentary on Kang et al.: Single-Port Laparoscopic Surgery Can Be Performed Safely and Appropriately for Colon Cancer: Short-Term Results of a Pilot Randomized Controlled Trial

The article in this issue by Kang et al. entitled “Single-Port Laparoscopic Surgery Can be Performed Safely and Appropriately for Colon Cancer: Short-Term Results of a Pilot Randomized Control Trial” ¹ adds to the growing body of literature which demonstrates that single-incision laparoscopic surgery (SILS) can be performed safely for colon and rectal procedures with an initial increase in difficulty but ultimately good outcomes. A simple search in PubMed reveals that currently there are hundreds of articles describing outcomes and techniques in single-port colon and rectal surgery. It has almost gotten to the point where the idea ceases to be controversial anymore. That is, unless you have struggled through a single-incision proctectomy and wondered what benefit you were providing your patient.

At first glance, colon and rectal surgery seems ideally suited to SILS. When one looks at cholecystectomy or appendectomy, the question is, are we adding benefit to the surgery by giving the patient 1 large incision instead of 3 or 4 small ones. The literature is mixed as to whether those patients have an increased rate of trocar site hernias, but it only makes intuitive sense that a single 2–2.5 cm incision has a higher hernia risk than a 1–1.5 cm incision or a 0.5 cm incision. SILS in colon and rectal surgery does not have a similar concern as the patient will already need a 2–3 cm extraction site to remove the specimen, which is tailor-made for a variety of single-incision laparoscopic platforms. I personally have performed many an SILS colectomy only to find at the end of the case that I needed to enlarge my incision just to accommodate the specimen. Stoma sites are also excellent candidates for extraction sites, and often the entire surgery, such as a subtotal colectomy, can be done through a well-placed stoma incision. These procedures can be particularly gratifying because at the end the patient has no noticeable incisions.

Cosmesis is another area where there appears to be a definite advantage. The total incision length for SILS colectomy versus multiport (MP) colectomy tends to be 1–3 cm less as demonstrated in this article as well as others. ² When done via a vertical transumbilical incision, the scar can be well hidden within the umbilicus, depending on the patient's body habitus. If done through a stoma site, again there may be no visible scars at all. In general, patient satisfaction scores and subjective evaluations of cosmesis after single-incision laparoscopy tend to be higher than for MP surgery. These results may be a little misleading as it is impossible to blind the patients to their surgical approach and there is no way to ensure that the surgeon did not extol the virtues of SILS before offering the approach to the patients, which could ultimately bias their satisfaction.

However, aside from cosmesis and the satisfaction of performing a procedure in a way that not every other surgeon can, it is not clear as to whether there is any distinct advantage to this technique. When those who have good outcomes using this technique discuss why their outcomes are better than MP, aside from cosmesis, they usually point to pain scores, length of stay (LOS), and return of bowel function. The difficulty of assessing these outcomes lies in the quality of the data that have been reported. The majority of the literature comes from single-institution series and the numbers are not large enough to find a difference in rare occurrences such as anastomotic leak. There is also a bias inherent to this procedure, because if the case is difficult it is converted to MP or open or if there is anticipation of difficulty the patient may never be offered this surgery, and thus, only cases that are amenable to the technique are often included in the data.

In a recent meta-analysis of the randomized control trials of SILS colectomy, the authors were only able to identify 2 articles and 82 patients. From the data it was unclear whether SILS had fewer complications, but it did look like the SILS patients went home a day sooner and one of the articles demonstrated that pain scores were better on day 1. ³ This article also analyzed the previously reported meta-analyses and demonstrated low methodologic quality. Another meta-analysis of nonrandomized studies included 547 colon cancer patients. They actually did not show any improvement in LOS or pain scores compared to MP, but they did demonstrate fewer postoperative complications and less bleeding from the SILS group. ⁴

Another question worth asking is, are there some procedures that may be better performed using the SILS technique. I will often perform a right hemicolectomy SILS because I find it adds very little difficulty to the procedure. A recent meta-analysis of the literature of SILS right hemicolectomy included 241 patients from 9 nonrandomized studies, and demonstrated no difference in any outcome between SILS and MP. ⁵ There are no other large, multi-institution studies on other types of colectomy or proctectomy to date.

In our article, Kang et al., demonstrate no difference in return of bowel function or LOS, and they only demonstrated a weak correlation between length of incision and postoperative pain, and only on postoperative day 1. All of these taken together demonstrate that while their technique may be no worse than MP laparoscopy, it is certainly no better either. Ultimately, asking the question is cosmesis worth the trade-off for increased procedural difficulty?

So, after making these points, one might imagine that I am not advocate for SILS colectomy. In fact, I am a proponent of this procedure, but the above question is one that every surgeon who performs these procedures needs to reconcile with. The way in which I have reconciled this issue is by allowing myself quick conversion to MP from SILS if at any point I feel like I am struggling with the procedure. If the procedure is simple and straightforward, then the cosmetic outcome is certainly worth it for certain patients. There is also literature to support reduced port surgery over conventional MP and often an SILS +1 approach, where a single 5 mm port placed is just as gratifying and significantly less difficult. I never praise SILS technique to a patient before a surgery because I do not want to feel like adding another 5 mm trochar is the same as failing at the surgery (this is the mind-set that could lead to increased complication rates from this technique).

The other point that allows me to justify performing these procedures is that the added difficulty allows me to keep my skill level high for when I might run up against a truly difficult MP case. I always tell my residents that if they can perform a surgery with an SILS technique, then they can easily do a procedure with an appropriate MP technique. For those who work at teaching hospitals, this is an excellent opportunity to teach residents how to perform minimally invasive procedures with different port placement than they may be used to and allows them to learn how to do camera work in close quarters and at difficult angles.

This technique may not ultimately be for everyone, and certainly if cosmesis does not matter to the patient then there may be no point in doing it at all. That being said, there is a role for SILS procedures, and we may find that as time goes on and technology improves, there are more significant benefits to this approach. Certainly, without SILS techniques there would be no natural orifice or transanal minimally invasive surgery. And so, pushing the limits of what we do now can only lead to new and unexpected advances in surgical techniques, which may revolutionize how we do what we do.