New studies do not support laparoscopic surgery for rectal cancer

Last Updated: 2015-10-06

By Megan Brooks

NEW YORK (Reuters Health) - Laparoscopic surgery is not better than traditional open surgery for rectal cancer and may be inferior, according to results of two randomized controlled trials published today in JAMA.

"The results have actually made us take a second-look at laparoscopic treatment of rectal cancer," Dr. James Fleshman of Baylor University Medical Center in Dallas, Texas, said in a JAMA podcast.

The American College of Surgeons Oncology Group Z6051 trial was a National Cancer Institute (NCI)-sponsored randomized trial that utilized 46 fully-trained expert surgeons at 35 sites across the US and Canada. Patients with curable locally advanced stage II or III rectal cancer within 12 cm of the anal verge were enrolled and the analysis are based on 240 patients with laparoscopic resection and 222 with open resection.

The primary outcome was a composite of pathologic oncology endpoints, namely completeness of total mesorectal excision, circumferential radial margin greater than 1 mm, and distal margin without tumor. All three must have been achieved for the surgery to be considered a success.

Based on the results laparoscopic treatment of rectal cancer "cannot be called noninferior to an open resection of the rectal cancer," Dr. Fleshman said.

Resection was successful in 81.7% of laparoscopic procedures versus 86.9% of open resections, a difference that did not reach the noninferiority margin (6%).

Negative circumferential radial margin was observed in 87.9% of laparoscopic resections and 92.3% of open resections and distal margin negativity was seen in more than 98% of patients irrespective of type of surgery.

"The overall results of the trial showed that the surgery was really pretty good," Dr. Fleshman commented. "At least 90% of all patients had a complete resection but when you split them into the two groups, laparoscopic had a higher incidence of incomplete total mesorectal excision and positive circumferential radial margins that made it slightly inferior to the open operation."

Operative time was also significantly longer for laparoscopic resection, while hospital length of stay, 30-day readmission rates, and severe complications were similar to open surgery.

Dr. Fleshman said, "There may be a use for laparoscopy in patients with rectal cancer, especially in those with small lesions high in the rectum. However, we now know that we cannot say that laparoscopic treatment of rectal cancer is absolutely equivalent or noninferior to open treatment of rectal cancer."

"There will be some soul-searching going on as we move forward," he said. "There may be a discussion whether or not robotic minimally invasive surgery is appropriate for rectal cancer. We do know that the open arm of this trial gave good results for patients with stage II and III rectal cancer, while the laparoscopic arm, while it was just slightly less good, cannot be called noninferior."

The patients in the trial will continue to be followed and the researchers will report overall survival and the disease-free survival at five years. "We think that this will tell us whether or not we have impacted the surgical survival or the oncologic outcomes of these patients," Dr. Fleshman said.

The second study in JAMA using the same design gave the same results.

The Australasian Laparoscopic Cancer of the Rectum (ALaCaRT) trial was a randomized noninferiority study of 475 patients with T1-T3 rectal cancer who underwent open resection or laparoscopic resection by accredited surgeons at 24 sites in Australia and New Zealand.

A successful resection was achieved in 82% of patients who had laparoscopic surgery and 89% of those who had open surgery, a difference that also failed to reach the researchers' noninferiority margin (8%).

The circumferential resection margin was clear in 93% of patients in the laparoscopic group versus 97% in the open surgery group; the distal margin was clear in 99% of patients in both groups and the total mesorectal excision was complete in 87% and 92%, respectively.

"Although the overall quality of surgery was high, these findings do not provide sufficient evidence for the routine use of laparoscopic surgery," Dr. Andrew R. L. Stevenson, of the University of Queensland, Brisbane, Australia, and colleagues conclude.

The authors of a linked editorial say these findings "substantiate" recent findings from similar randomized trials and suggest that laparoscopic resection "may not be oncologically justified in many patients requiring proctectomy for rectal cancer."

"The studies do not signal a moratorium on these approaches, but surgeons must proceed in a judicious manner to ensure that patients are informed about the benefits and risks associated with minimally invasive and open operations," advise Dr. Scott A. Strong and Dr. Nathaniel J. Soper of the Northwestern University Feinberg School of Medicine in Chicago.

Neither study had commercial funding. Several authors have disclosed relevant relationships, all listed with the original article.

SOURCE: http://bit.ly/1McLJoL, http://bit.ly/1LvCp4P, and http://bit.ly/1NjwwYE

JAMA 2015.