The Effectiveness and Safety of Open Versus laparoscopic Surgery for Rectal Cancer after Preoperative Chemo-radiotherapy: A Meta-Analysis

Abstract

Background: Only a limited number of studies considered the combined chemo-radiation therapy after surgery for treating locally advanced rectal cancer. Comparative studies on laparoscopic and open procedures indicated that laparoscopy surgery may be associated with fewer postoperative complications. Despite encouraging results from rectal cancer patients who received neoadjuvant chemo-radiotherapy prior to laparoscopic surgery, the acceptance of this procedure remains controversial, and conflicting evidence exists only in the form of retrospective trials.

Objectives: Since laparoscopic surgery was introduced into clinical practice to treat rectal cancer after neoadjuvant chemo-radiotherapy, it has been discussed controversially whether laparoscopic surgery can be performed as effectively as an open procedure. To overcome the biases inherent in any nonrandomized comparison, we analyzed the propensity-matched analysis and randomized clinical trial. In this study, we set out to determine whether laparoscopic resection was non-inferior to open resection in treatment outcomes of rectal cancer after neoadjuvant chemo-radiotherapy.

Methods: Publications on laparoscopic surgery in comparison with open thoracotomy in treatment outcomes of rectal cancer after neo-adjuvant chemo-radiotherapy to November 2017 were collected. Summary hazard ratios (HRs) of endpoints of interest such as 3-OS (overall survival), 3-DFS (disease-free survival), and individual postoperative complications were analyzed in all trials. By using fixed- or random-effects models according to the heterogeneity, meta-analysis Revman 5.3 software was applied to analyze combined pooled HRs.

Results: A total of 6 trials met our inclusion criteria. The pooled analysis of 3-DFS showed that laparoscopic surgery did not improve disease -free survival, compared with open thoracotomy (OR =1.48, 95% CI 0.95 - 2.29; P = 0.08), as well with the 3-OS (OR=0.96, 95%CI=0.66-1.41, P=0.084). The pooled result of duration of surgery indicated that laparoscopic surgery had a tendency towards a longer surgery time (SMD= 43.96, 95% CI 34.04- 53.88; P < 0.00001) and a shorter hospital stay (SMD= -0.97, 95% CI -1.75- -0.18; P=0.02). However, no significant differences between laparoscopic surgery and open thoracotomy were observed in terms of the meta-analysis on the number of removed lymph nodes (SMD =-0.37, 95% CI -0.1.77 - 1.03; P = 0.60), blood loss (SMD =-21.30, 95% CI -0.48.36 - 5.77; P = 0.12), positive circumferential resection margin (OR =0.73, 95% CI 0.22- 2.48; P = 0.61) or postoperative complications (OR =0.89, 95% CI 0.67 - 1.17; P = 0.40) l.

Conclusion: The current data supported the concept that laparoscopic surgery had correlated with a longer operative time but a shorter hospital stay, without superior advantages in short-term survival rates or oncologic efficiency for locally treating advanced rectal cancer after neoadjuvant chemoradiotherapy. However, prospective investigation on long-term oncological results from laparoscopic surgery is required in the future to verify the benefits of laparoscopic surgery over open surgery after chemo-radiation therapy for treating locally advanced rectal cancer.

Keywords: Rectal cancer; chemo-radio therapy; laparoscopic surgery; meta-analysis; neoadjuvant therapy; open surgery..