A battle of surgical strategies: Clinically enlarged lateral lymph nodes in patients with locally advanced rectal cancer; extended mesorectal excision (e-TME) versus traditional surgery (TME-alone) a meta-analysis.

Background: The infiltration of lateral lymph nodes (LLN) plays a crucial role in the staging and treatment of individuals with locally advanced rectal cancer (LARC). This meta-analysis aimed to compare the efficacy of extended mesorectal excision (eTME) versus traditional mesorectal excision (TME-alone) in patients with clinically enlarged (LLN) concomitant neoadjuvant chemoradiation.

Methods: This study is registered with PROSPERO (CRD42023457805). A comprehensive literature search was conducted across PubMed/Medline, Scopus, Cochrane Library, EMBASE, Web of Science, and EBSCO databases for comparative studies published until June 2024. The study included patients with clinically enlarged LLN concomitant with neoadjuvant chemoradiation in rectal cancer who underwent either eTME or TME alone. Primary outcomes included local recurrence (LR), lateral local recurrence (LLR), overall survival (OS), distant metastasis, and disease-free survival (DFS).

Results: The pooled mean for LR was 6.6 % in the TME group and 4.8 % in the eTME group, with no significant difference between the groups (OR, 0.569; 95 % CI, 0.180-1.792; P = 0.33). Similarly, the pooled LLR rates were 38.5 % for TME and 55.8 % for eTME, indicating a higher recurrence rate in the eTME group (P = 0.65). In the term of the (OS) rates were 93.7 % for TME and 93.2 % for eTME, with no significant difference (P = 0.56). The (DFS) rates were 84.6 % for TME and 86 % for eTME, with no significant difference (P = 0.38). Additionally, the distant recurrence rates were 6.8 % for TME and 17.5 % for eTME, with no significant difference (P = 0.479).

Conclusion: Our meta-analysis provides reliable information on the efficacy of eTME versus TME-alone in patients with clinically enlarged LLN concomitant with nCRT in rectal cancer, as we addressed previous limitations for a more accurate comparison. While the (eTME) does not show significant oncologic benefits over (TME alone), the study emphasizes the need for careful patient selection and further research to refine treatment guidelines. Individual patient- and tumor characteristics should guide the most appropriate surgical strategy.