Surgical, oncological, and functional outcomes of local and radical resection after neoadjuvant chemotherapy or chemoradiotherapy for early- and mid-stage rectal cancer: a systematic review and meta-analysis.

Background: Radical resection is typically the standard treatment for early- and mid-stage rectal cancer as local resection may result in a high rate of recurrence and risk of distant metastasis. A growing number of studies have shown that local excision after neoadjuvant chemotherapy or chemoradiotherapy can significantly reduce recurrence rates and is a feasible strategy to preserve the rectum as an alternative to conventional radical resection.

Objective: This study aims to compare the efficacy of local resection after neoadjuvant chemotherapy or chemoradiotherapy with radical surgery for early- and mid-stage rectal cancer and to report the evidence-based clinical advantages of both techniques.

Methods: Clinical trials comparing oncologic and perioperative outcomes of local and radical resection after neoadjuvant chemotherapy or chemoradiotherapy in patients with early- to mid-stage rectal cancer were searched in PubMed, Embase, Web Of Science, and Cochrane databases, and a total of 5 randomized controlled trials and 11 cohort study trials were included.

Results: In terms of oncology and perioperative outcomes, there were no statistically significant differences between the radical resection group and the local resection group in terms of OS [HR = 0.99, 95%CI (0.85, 1.15), p = 0.858], DFS [HR = 1.01, 95%CI (0.64, 1.58), p = 0.967], distant metastasis rate [RR = 0.76, 95%CI (0.36,1.59), p = 0.464], and local recurrence rate [RR = 1.30, 95%CI (0.69, 2.47), p = 0.420]. However, there were significant differences in the outcomes of complications [RR = 0.49, 95% CI (0.33, 0.72), p < 0.001], length of hospital stays [WMD =  - 5.13, 95%CI (- 6.22, - 4.05), p < 0.001], enterostomy [RR = 0.13, 95%CI (0.05, 0.37), p < 0.001], operative time [- 94.31, 95%CI (- 117.26, - 71.35), p < 0.001], and emotional functioning score [WMD = 2.34, 95% CI (0.94, 3.74), p < 0.001].

Conclusion: Local resection after neoadjuvant chemotherapy or chemoradiotherapy may be an effective alternative to radical surgery in patients with early and middle rectal cancer.