Thursday, January 10, 2013
One of the main advances in surgery over the past 25 years has been the ability to operate in the abdominal cavity without creating large incisions. Removal of the gallbladder, which once required a 10-inch incision in the abdominal wall, can now be performed laparoscopically through one or more incisions measuring less than1 inch, with less pain, reduced scarring, and faster recovery. Many abdominal conditions, including colon cancer, are now treated laparoscopically.
The adoption of laparoscopy in rectal cancer has been much slower. The standard operation for rectal cancer — total mesorectal excision (TME) — is complex and technically demanding. The rectum, located in the narrow bony pelvis, is surrounded by crucial anatomical structures, and the long, rigid, non-articulating laparoscopic instruments are not well suited to precise dissection in the pelvis. The laparoscopic camera provides only two-dimensional vision without depth of perception. Finally, the surgeon is forced to operate in an ergonomically unfavorable position that impairs dexterity and increases fatigue.
The da Vinci® Surgical System provides an alternative to open and laparoscopic surgery by combining high-definition 3-D imaging with articulating instruments that mimic the movements of the human hand. It facilitates minimally invasive surgery by enhancing visualization and increasing dexterity and precision.
The robot is especially helpful when operating in deep and narrow fields such as the pelvic cavity. (1) Consequently — as many urologic and gynecologic cancer surgeons have already done — colorectal surgeons are now incorporating robotics into their armamentarium. The potential advantages of the robotic approach include a more precise dissection that may enhance the probability of removing the tumor and reduce the risk of damaging the nerves that control urinary and sexual function.
The experience published so far indicates that robotic TME is safe compared to both open and laparoscopic TME. Short-term outcomes, measured as length of skin incision, use of narcotics, and length of hospital stay, are equal or superior to laparoscopic TME. Oncologic results, measured as completeness of the mesorectal excision, the proportion of patients with negative circumferential resection margins, and the number of lymph nodes retrieved, are comparable to, or in some cases somewhat better than, the results of either open or laparoscopic TME. (2) However, the results of these small, retrospective case series reporting single-institution experiences need to be confirmed in large prospective randomized trials.
But even proof that long-term results are equivalent to, or even somewhat better than, those of laparoscopic or open TME may not be sufficient to justify the widespread adoption of robotic surgery for rectal cancer. The robotic surgical system is expensive to purchase and maintain, (3) and many centers may not be able to afford it.
As with laparoscopy, robotic surgery has a learning curve. Learning the technique may take as many as 15 to 25 procedures, but mastering it may require many more. (4) Outcomes for complex surgeries tend to be better in high-volume centers. The steep learning curve for robotic surgery may accentuate the outcome-volume relationship observed for open and laparoscopic TME, ultimately confining robotic colorectal surgery to centers where large numbers of such operations are performed each year. (5)
With an aggregate experience of more than 500 colon and rectal cancer surgeries per year, our colorectal surgeons at Memorial Sloan Kettering Cancer Center are in the best position to take advantage of this promising technology. We have five of the latest-generation da Vinci® SI HD robots and we use the robotic approach whenever possible to treat this disease. But robotic surgery is only one of the many tools we use, when possible, in our multidisciplinary team approach to treatment. Our overarching goal is to improve results and individualize therapy for our patients. We have achieved very high rates of sphincter preservation for our rectal cancer patients, and we offer the best quality of care available. Our institution is also the most experienced center for colorectal cancer surgery — including robotic TME — in New York City, and the largest center in the Northeast for all types of minimally invasive colorectal surgery. As one of the leading cancer centers in the world, we have embraced robotic surgery for the treatment of a number of tumors. We understand that it may take years for the true potential of the robotic system to be revealed, but we are committed to participating in that process of discovery.