Requirement for a standardised definition of advanced gastric cancer

Each year, ~988,000 new cases of stomach cancer are reported worldwide. Uniformity for the definition of advanced gastric cancer (AGC) is required to ensure the improved management of patients. Various classifications do actually exist for gastric cancer, but the classification determined by lesion depth is extremely important, as it has been shown to correlate with patient prognosis; for example, early gastric cancer (EGC) has a favourable prognosis when compared with AGC. In the literature, the definition of EGC is clear, however, there is heterogeneity in the definition of AGC. In the current study, all parameters of the TNM classification for AGC reported in each previous study were individually analysed. It was necessary to perform a comprehensive systematic literature search of all previous studies that have reported a definition of ACG to guarantee homogeneity in the assessment of surgical outcome. It must be understood that the term 'advanced gastric cancer' may implicate a number of stages of disease, and studies must highlight the exact clinical TNM stages used for evaluation of the study.