Oncological outcomes of local excision versus radical surgery for early rectal cancer in the context of staging and surveillance: A systematic review and meta-analysis

Background: Local resection (LR) methods for rectal cancer are generally considered in the palliative setting or for patients deemed a high anaesthetic risk. This systematic review and meta -analysis aimed to compare oncological outcomes of LR and radical resection (RR) for early rectal cancer in the context of staging and surveillance assessment. Methods: A literature search of MEDLINE, Embase and Emcare databases was performed for studies that reported data on clinical outcomes for both LR and RR for early rectal cancer from January 1995 to April 2023. Metaanalysis was performed using random -effect models and between -study heterogeneity was assessed. The quality of assessment was assessed using the Newcastle -Ottawa Scale for observational studies and the Cochrane Risk of Bias 2.0 tool for randomised controlled trials. Results: Twenty studies with 12,022 patients were included: 6,476 patients had LR and 5,546 patients underwent RR. RR led to an improvement in 5 -year overall survival (OR 1.84; 95 % CI 1.54 -2.20; p < 0.0001; I- 2 20 %) and local recurrence (OR 3.06; 95 % CI 2.02 -4.64; p < 0.0001; I- 2 39 %) when compared to LR. However, when staging and surveillance methods were clearly adopted in LR cases, there was an improvement in R0 rates (96.7 % vs 85.6 %), 5 -year disease -free survival (93.0 % vs 77.9 %) and overall survival (81.6 % vs 79.0 %) compared to when staging and surveillance was not reported/performed. Conclusions: LR may be appropriate for selected patients without poor prognostic factors in early rectal cancer. This study also highlights that there is currently no single standardised staging or surveillance approach being adopted in the management of early rectal cancer. A more specified and standardised preoperative staging for patient selection as well as clinical and image -based surveillance protocols is needed.