Oncologic Safety of Laparoscopic Rectal Cancer Surgery Is Dubious

Patients undergoing laparoscopic rectal resection (LRR) have increased risk for incomplete tumor excision compared to open surgery, according to a new study.

Researchers at Henri Mondor University Hospital, Hospital Universitario Doctor Peset, and Rothschild Hospital conducted a meta-analysis of studies to examine the evidence concerning the pathologic outcomes of LRR versus open rectal resection (ORR) for rectal cancer. Of 369 records screened, 14 RCTs were selected for the qualitative and quantitative analyses. Main outcomes and measures included rate of positive circumferential resection margin (CRM) and the quality of mesorectal excision.

The researchers identified a positive CRM in 7.9% and 6.1% percent of patients undergoing LRR and ORR, respectively. In five studies, a noncomplete mesorectal excision occurred in 13.2% and 10.4% of LRR and ORR patients, respectively. There was no significant difference between LRR and ORR in the distal resection margin involvement, the mean number of lymph nodes retrieved, mean distance to the distal margin, and the mean distance to radial margins. The study was published on February 8, 2017, in JAMA Surgery.

“Based on the available evidence, the risk for achieving noncomplete mesorectal excision is significantly higher in patients undergoing LRR, compared with ORR,” concluded lead author Aleix Martínez-Pérez, MD, of Henri Mondor University Hospital, and colleagues. “These findings question the oncologic safety of laparoscopy for the treatment of rectal cancer. However, long-term results of the ongoing RCTs are awaited to assess whether these pathologic results have an effect on disease-free and overall patient survival.”

Total mesorectal excision is used in the treatment of colorectal cancer, during which a significant length of the bowel around the tumor is removed. It involves a low anterior resection for tumors of the middle and the lower rectum, wherein it is essential to remove the rectum along with the mesorectum up to the level of the levators.