Objective:To evaluate the significance of p16,p21 WAF1 ,CDK4,cyclin D1protein expression and their relationship in gastric carc inoma a nd precancerous lesion.Methods :The S-P immunohistochemical method wa s used to detect the expression of p16,p21 WAF1 ,CDK4,cyclin D1in gastric carcinom a,atypical hyperplasia,chronic su p erficial gastritis,and normal gastric mucosa.Results:The positive expression rates of p16and p21 WAF1 protein in gastric carcinoma were 52.7%and 30.9%respectivel...