[The significance of p16 protein and Ki-67 antigen expression in gastric mucosa-associated lymphoid tissue lymphoma].

OBJECTIVE: To detect the expression of p16 protein and Ki-67 antigen in gastric mucosa-associated lymphoid tissue lymphoma (MALTL) and normal gastric mucosa and to investigate the clinical significance of their expression in the occurrence and development of gastric MALTL. METHODS: 47 samples of gastric MALTL diagnosed pathologically in the department of pathology of the PLA General Hospital from March 1993 to June 2005 were collected. By using immunohistochemical methods, the expression of p16 protein and Ki-67 antigen was detected in 20 samples of normal gastric tissue and the 47 samples of gastric MALTL. RESULTS: The positive rate of p16 protein was 21.3% (10/47) and 90.0% in gastric MALTL and normal gastric tissue respectively. The positive rate of p16 protein in gastric MALTL was lower than that in normal gastric tissue (P < 0.05). The expression of p16 was related to the degree of lymph node metastasis. The positive rate of Ki-67 labelling index (LI) in gastric MALTL was higher than that in normal gastric tissue. A negative correlation was found between the expression of p16 protein and Ki-67 LI (P < 0.05). CONCLUSIONS: Detection p16 and Ki-67 may help to predict the possibility of lymph node metastasis and prognosis in gastric MALTL.