Many researchers have studied the expression of Ki67 & P53 in both positive and negative HP gastritis, gastric ulcer, and cancer. In this study, the expression of Ki67 & P53 were assessed only in positive HP gastritis and the expression of Ki67 & P53 were detected in 83.3% of cases, a higher percentage more than many other studies, such as: Azza et al (25) study in which Ki67 & P53 expression were 54.5%, 72.7% respectively, Cesar et al (26) study in which P53 expression was 45%, Afaf et al (27) study in which P53 expression was 32.7%, while in Morales-Fuentes et al (28) study, the P53 expression was 91% which is more than this study. The differences could be due to the different sample size of the cases taken by the studies, different genetic background, variation in food types between the nations, etc. It is worth saying that despite the similarity of the overall percentage of positive cases for the two markers in the present study, there were positive cases for Ki67 and negative for P53 and vice versa in six cases, and only two cases were negative for both markers.
In this study, the age range from 14-84 years with mean 46 years ± 17.2, male to female ratio was 7:8, in Morales-Fuentes et al (28) study the range of age was 55-81 years and male to female ratio 5:6, while in Azza et al (25) study the patients mean age was 53 years ± 5.1 and male to female ratio 1.75:1, and in Zainab et al (29) study the patients’ age range was 11 - 82 years (mean of 46.5 years) with a male to female ratio of 1.38:1. Ki67 & P53 expressions in this study were significantly detected more in age group (42-55) years, also the expression of both Ki67 & P53 were seen in females more than males .This discrepancy of results among different studies might be due to bias in data collection of some researches.
In the present study, 86.2% of the studied cases with chronic infiltration of inflammatory cells showed positive Ki67 & P53 expression, while in the study by Afaf et al (27) 32.7% of these cases had positive expression of P53.
Ki67 & P53 were expressed in 92% of cases with infiltration of PMN cells, while in the study by Afaf et al (27) 66.7% of these cases had positive expression of P53.
Furthermore, 92.3% of cases with atrophy had positive Ki67 & P53 expression, while in the study by Afaf et al (27) 26.1% only of the cases had positive P53 expression.
Although they are few detected in this study, all cases with intestinal metaplasia showed positive P53 expression, and only half of them showed Ki67 expression, while in Mahmoudzadeh et al (23) study 60%, 55% only of these cases had positive P53, Ki67 expression respectively, while in Afaf et al (27) study 31.7% only of these cases had positive P53 expression. On the contrary to the results of this study, Forones et al. (30) found in their study that all samples with intestinal metaplasia had negative expression of P53, and they supposed that the mutation of P53 occur in latter stages of gastric carcinogenesis. The explanation of the reason for the lack of the presence of the intestinal metaplasia in large number of cases in this research is belong to exclusion of negative cases of HP, and as it is known, this bacterium does not colonize in the intestinal metaplastic tissues.
Regarding the cases with dysplasia, again all of them showed positive expression of P53, while only 2/3 of them showed Ki67expression ,while in Mahmoudzadeh et al (23) study 57.89%, 26.31% only of these cases had positive expression respectively.