BACKGROUND: Stomach cancer is rated as the third malignant neoplasm in the world, being the second most frequent cause of death. However, its incidence has been declining in the last few years in countries like the United States, England and Australia, and in countries where its incidence has always been high - Japan, China, Korea and in the Eastern part of Asia, which has an estimated 780 cases per year per 100,000 inhabitants. AIM: To describe the cytophotometric expression of Ki-67 and CD-34 with comparison to their expression in stomach adenocarcinomas. METHODS: 60 paraffin blocks containing specimens of gastric adenocarcinomas, were initially selected in the Pathology services of the Gama Hospital - Brasília, DF an at the Dom Orione Hospital - Araguaiana, TO. The immunohistochemistry process using Ki-67 and CD-34 was performed at the Laboratório de Citologia e Histopatologia Ltda. -CITOLAB, Curitiba, PR. A total of 35 paraffin blocks were selected among the other 60 previously selected, being used in histological studies as well as for the immunohistochemistry process. These were analyzed using the computerized image cytophotometric system (SAMBA 4000) at the Institute of Medical Research of the Hospital Universitário Evangélico de Curitiba. The parameters studies and analyzed through this system were the labeling index and optical density for both of the tumoral markers being independently analyzed and latter compared with each other. RESULTS: Of the 35 slides, 15(42,85%) showed the expression of Ki-67; 26 (74,28%) of CD-34 and 12 slides (34,28%) showed the expression of both markers. When the labeling indexes between Ki-67 and CD-34 were compared, a significant difference was observed (P<0,001) favoring CD-34. When the optical density of the two markers was compared, a significant difference (P<0,001) was also observed, favoring CD-34. CONCLUSIONS: The average labeling index for Ki-67 was of 36,85%, where as the optical density was of 29,33 pixels. CD-34 showed a labeling index of 84,86% and an average 49,84 pixels regarding the optical density. When the labeling index and optical density were compared between both of the markers, a significant difference was established favoring CD-34 in both of the parameters analyzed.
Stomach neoplasm; Immunohistochemistry; CD-34
