PCNA EXPRESSION IN GASTRIC ADENOCARRCINOMA Objectives: To evaluate the level of PCNA expression and its relationship with the endoscopic and histopathological features of patients with gastric antral adenocarcinoma. Subjects and methods: The study was performed on 150 cases of gastric adenocarcinoma operated at Hanoi K Hospital from january 2018 to december 2019, using an crosssectional descriptive method. Results: High expression level of PCNA was found in 54,7% of gastric adenocarcinomas. High expression of PCNA in infiltrates, polyps, ulcers and polypoid was 33,3%, 50%, 53,8% and 61,1% (p > 0.05). According to Lauren's histological classification, 61,5% of intestinal type tumors had PNCA high expression compared to 29,4% of diffused types and 71,4% of mixed types, respectively (p < 0.01). High expression level of PCNA was different in papillary 100% mixed 71.4% tubular 63,6% mucinous 44.4% and signet ring cell 29,4% 1Trường Đại học Y Dược - Đại học Thái Nguyên 2Trường Đại học Khoa học - Đại học Thái Nguyên Chịu trách nhiệm chính: Trần Ngọc Thụy Email: tranngocthuyk7@gmail.com Ngày nhận bài: 26.9.2022 Ngày phản biện khoa học: 18.11.2022 Ngày duyệt bài: 28.11.2022 types (p < 0.05). High expression of PCNA in different grades: 41,4% of well-differentiated, 69,6% of moderately differentiated and 47,7% of poorly differentiated tumors (p < 0.05).