Effectiveness of Organ Preservation for Locally Advanced Rectal Cancer With Complete Clinical Response After Neoadjuvant Chemoradiotherapy: Bayesian Network Meta-analysis.

Abstract

Background: Neoadjuvant chemoradiotherapy followed by radical surgery is the common treatment for patients with locally advanced rectal cancer. Presently, for patients with complete clinical response after neoadjuvant chemoradiotherapy, organ preservation ("watch-and-wait" and local excision strategies) has been increasingly favored. However, the optimal treatment for patients with complete clinical response remains still unclear.

Objective: This study aimed to use Bayesian meta-analysis to determine the best treatment for patients with locally advanced rectal cancer with complete clinical response among radical surgery, local excision, and watch and wait strategies.

Data sources: PubMed, Web Of Science, Cochrane Library and Embase(Ovid) were searched until December 31, 2023.

Study selection: Studies that compared two or more treatments for patients with complete clinical response were included.

Intervention: The analysis was completed via Bayesian meta-analysis using random-effects model.

Main outcomes: Surgery-related complications, local recurrence, distant metastasis, 5-year overall and disease-free survival rate.

Result: Eleven articles met inclusion criteria. The groups of watch and wait and local excision exhibited a higher rate of tumor recurrence compared to radical surgery group (OR [95% CI]: watch and wait VS radical surgery: 9.10 [3.30, 32.3], local excision VS radical surgery: 2.93 [1.05, 9.95]). The distant metastasis, overall and disease-free survival rates of 3 treatments were not statistically different. The radical surgery group had the most number of stoma, and had the greatest risk of morbidity than the watch and wait group (OR[95%CI]: watch and wait VS radical surgery: 0.00 [0.00, 0.12]).

Limitations: The study included only 1 randomized controlled trial compared to 10 observational studies, which could affect overall quality. Funnel plots of disease-free survival rates and stoma suggest significant publication bias among studies which compared radical surgery with watch and wait strategy.

Conclusion: The watch and wait strategy could be optimal for patients with locally advanced rectal cancer with complete clinical response after neoadjuvant chemoradiotherapy.