Martínez-Pérez A et al. JAMA Surg 2017
Abstract
Importance Rectal resection with mesorectal excision is the mainstay treatment for rectal cancer.
Objective To review and analyze the evidence concerning the pathologic outcomes of laparoscopic (LRR) vs open (ORR) rectal resection for rectal cancer.
Data Sources The Cochrane Central Register of Controlled Trials, MEDLINE (through PubMed), EMBASE, Scopus databases, and clinicaltrials.gov were searched for randomized clinical trials (RCTs) comparing LRR vs ORR.
Study Selection Only RCTs published in English from January 1, 1995, to June 30, 2016, that compared LRR with ORR for histologically proven rectal cancer in adult patients and reported pathologic outcomes (eg, positive circumferential resection margin, and complete mesorectal excision) were eligible for inclusion. Of 369 records screened, 14 RCTs were selected for the qualitative and quantitative analyses.
Data Extraction and Synthesis Two independent reviewers performed the study selection and quality assessment. Random-effects models were used to summarize the risk ratio (RR) and mean differences.
Main Outcomes and Measures The rate of positive circumferential resection margin (CRM), defined as 1 mm or less from the closest tumor to the cut edge of the tissue, and the quality of mesorectal excision (complete, nearly complete, or incomplete).
Results The meta-analysis included 14 unique RCTs with 4034 unique patients. Of 2989 patients undergoing rectal resection, a positive CRM was found in 135 (7.9%) of 1697 patients undergoing LRR and 79 (6.1%) of 1292 patients undergoing ORR (RR, 1.17; 95% CI, 0.89-1.53; P = .26; I2 = 0%) in 9 studies. A noncomplete (nearly complete and incomplete) mesorectal excision was reported in 179 (13.2%) of 1354 patients undergoing LRR and 104 (10.4%) of 998 patients undergoing ORR (RR, 1.31; 95% CI, 1.05-1.64; P = .02; I2 = 0%) in 5 studies. The distal resection margin involvement (RR, 1.12; 95% CI, 0.34-3.67; P = .86), the mean number of lymph nodes retrieved (mean difference, 0.05; 95% CI, −0.77 to 0.86; P = .91), the mean distance to the distal margin (mean difference, 0.01 cm; 95% CI, −0.12 to 0.15 cm; P = .87), and the mean distance to radial margins (mean difference, −0.67 mm; 95% CI, −2.16 to 0.83 mm; P = .38) were not significantly different between LRR and ORR. The risk for bias was assessed as low in 10 studies, high in 3, and unknown in 1. The overall quality of the evidence emerging from the literature was rated as high.
Conclusions and Relevance Based on the available evidence, the risk for achieving a noncomplete mesorectal excision is significantly higher in patients undergoing LRR compared with ORR. 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.
https://jamanetwork.com/journals/jamasurgery/fullarticle/2600157
From my point of view, the current oncological surgery should be based on logical image parameters that allow a preoperative staging to be carried out as accurately as possible. Thus, transendoscopic ultrasound, computerized and contrasted axial tomography, are current pillars to be able to define the staging. As in other organs, lymphadenectomy should be based on the basis that nodes would be taken or not. There is not an important experience in the sentinel lymph node of rectal cancer so far, but it will be useful during the intraoperative period.
So the ability of the laparoscopic doctor and the philosophy of the use of current techniques could define a better or worse procedure. It would be interesting in that meta analysis to have defined the surgical experience in these operations.
Dr Aguirre
Would a meta-analysis provide us the Truth of benefit or being worse?
The problem is not only to define cases that are similar, there are other biases that must be taken into account when making comparisons, such as experience, techniques used, preoperative and post-operative stages, that is my point of view. However, the work has its great value and can lead to new research.
Good point - however, too often meta-analysis seem to be interpreted as another kind of holy grail and due to this: we need to stay cautious about such
“Biology is King; selection of cases is Queen, and the technical details of surgical procedures are princes and princesses of the realm who frequently try to overthrow the powerful forces of the King and Queen, usually to no long-term avail, although with some temporary apparent victories.” Blake Cady
- Badges
- Science method
- Similar topics
- Mathematics
- Statistics
- Statistical Techniques
- Meta-Analysis