Radical versus Local Surgical Excision for Early Rectal Cancer: A Systematic Review and Meta-Analysis.

Background: Radical excision (RE) for rectal cancer carries a higher risk of mortality and morbidity, while local excision (LE) could decrease these postoperative risks. However, the long-term benefit of LE is still debatable.

Aim: To study the effectiveness of LE versus RE in T1 and T2 rectal cancer.

Methods: A systematic review and meta-analysis was conducted using key databases like PubMed and ClinicalTrials.gov. Only cohort studies and randomized controlled trials were included. RevMan 5.4 tool was used for data analysis. Both clinical and statistical heterogeneity of the studies were assessed, and I² >75% was considered as highly heterogeneous. The primary outcomes being measured were 5-year overall survival (OS) and 5-year disease free survival (DFS). A subgroup analysis of patients with T1-only was also conducted, without adjuvant chemo/radiotherapy.

Results: A total of 18 studies were included for final meta-analysis. Four were RCTs, while the other 15 were retrospective cohort studies. One included study had data from both RCT and non-RCT study groups. Nine studies were multicentered or national studies while nine were unicentral.There was no difference in risk ratio (RR) between OS: RR 0.95, 95% Confidence Interval (CI) [0.91, 0.99] and DFS: RR 0.93, 95% CI [0.87, 1.01]. There were lower hazards ratios in OS: RR 1.41, 95% CI [1.14, 1.74] and DFS: RR 1.95, 95% CI [1.36, 2.78] with radical, as compared to LE. Lower recurrence rate was associated with RE. Random effect model was used due to clinical heterogeneity between studies (different surgical procedures, tumor staging, adjuvant chemo or radiotherapy).

Conclusions: LE for early-stage rectal cancer has lower 5-year OS and DFS than RE, with higher local recurrence rate. However, LE is associated with lower early postoperative mortality, morbidity and length of stay as compared to RE.