Table 2. GC classification algorithm based on immunohistochemistry and in-situ hybridization.

Sample size	Markers	Findings	References
438 GC patients	EBER, MLH1, PMS2, MSH2, MSH6, HER2, EGFR, MET, PTEN, TP53	Relationship between protein/RNA expression levels and unique clinical characteristics	Kim et al. [24]
244 GC patients	EBER, MLH1, MSH2, MSH6, PMS2, TP53, E-cadherin, EGFR, HER2, Lauren classification	Association of molecular markers and clinicopathological characteristics including sex, tumor location, and overall survival	Birkman et al. [25]
146 GC patients	EBER, MLH1, PMS2, MSH2, MSH6, TP53, E-cadherin	Clinicopathologic features including significant differences in prognosis corresponding to earlier molecular classification	Setia et al. [26]
349 GC patients	EBER, MLH1, E-cadherin, TP53, HER2	Clinicopathologic features including significant differences in prognosis corresponding to earlier molecular classification	Ahn et al. [27]
206 GC patients	MLH1, PMS2, MSH2, MSH6, TP53, E-cadherin,	Subtypes associated with survival, recurrence rate, and other clinical characteristics corresponding to TCGA classification	Díaz Del Arco et al. [28]
104 GC patients	ERER, MLH1, TP53	Subtypes associated with survival and HER2 overexpression comparable to TCGA classification	Gonzalez et al. [29]
993 GC patients	EBER, TP53, EGFR, HER2, MET, Lauren classification	Survival predicting histo-molecular classification and screening protocol for RTK amplified GCs	Park et al. [30]

GC = gastric cancer; EBER = Epstein–Barr encoding region; MLH1 = mutL homolog 1; TP53 = tumor suppressor p53; PMS2 = PMS1 homolog 2; MET =mesenchymal epithelial transtion; PTEN = phosphatase and tensin homologue deleted on chromosome 10; HER2 = human epidermal growth factor receptor 2; EGFR = epidermal growth factor receptor; TCGA = The Cancer Genomic Atlas; RTK = receptor tyrosine kinase; MSH = mutS homologue.