“…The pathogenesis of the gastric SCC remains obscure, but several theories have been suggested as follows: First, tumor growth in area of ectopic squamous cell nest [12][13][14] ; Second, tumor growth in squamous metaplasia of glandular epithelium 15,16 ; Third, pre-existing adenocarcinoma that undergoes squamous differentiation 8,17 ; Fourth, tumor from toti-potential undifferentiated cell. 18 In this case, the 3rd theory can be excluded because no evidence of adenocarcinoma was found out on the pathological result.…”