A systematic review of minimal length of lroximal margin in gastric adenocarcinoma resection

For early distal gastric cancers, a proximal margin (PM) > 2-3 cm might probably be sufficient. For advanced tumors, many confounding factors have a prognostic impact on survival and recurrence and negative margin involvement may be more relevant than negative margin length.

Introduction: In gastric cancer surgery, microscopic positive margin is a poor prognostic factor whereas complete resection with tumor-free margins remains a challenging issue. European guidelines recommended a macroscopic margin of 5 or even 8 cm for diffuse-type cancers to achieve R0 resection. However, it is unclear if the length of negative proximal margin (PM) could have a prognostic impact on survival. We aimed to perform a systematic review of the literature analyzing PM length and its prognostic impact in gastric adenocarcinoma.

Material and methods: Pubmed and Embase databases were searched for "gastric cancer" or "gastric adenocarcinoma," combined with "proximal margin," between January 1990 and June 2021. English-written studies that specified PM length were included. Survival data, in relation to PM, were extracted.

Results: Twelve retrospective studies, with a total number of 10,067 patients, met inclusion criteria and were analyzed. Mean length of proximal margin on the whole population varied from 2.6 to 5.29 cm. Three studies found minimal PM cut-off to improve overall survival in univariate analysis. Concerning recurrence-free survival analysis, only 2 series showed better results with PM > 2 or > 3 cm, using Kaplan-Meier method. Multivariate analysis demonstrated an independent impact of PM on overall survival in 2 studies.

Conclusion: For early distal gastric cancers, a PM > 2-3 cm might probably be sufficient. For advanced or proximal tumors, many confounding factors have a prognostic impact on survival and recurrence and negative margin involvement may be more relevant than negative margin length.