Prognostic significance of peritumoural and intratumoural budding in intestinal-type gastric adenocarcinoma.

Abstract Background and study aims Tumour budding (TB) at the invasive front, termed peritumoural budding (PTB), is an established prognostic factor for many solid tumours. However, intratumoural budding (ITB) in gastric adenocarcinoma (GAC), which is frequently observed at the tumour centre, particularly in tumour biopsy tissues, remains poorly understood. Hence, we aimed to determine the correlation of ITB with PTB and their connection with clinicopathological characteristics as well as their prognostic value in GAC. Patients and methods We investigated a total of 153 cases of GAC wherein tissues were primarily resected and their related clinicopathological data. A continuous series of paraffin-embedded tissues was stained by haematoxylin–eosin staining, and budding cells were identified by immunohistochemical staining. PTB and ITB were counted in five fields with the highest density of tumour buds. The selected area was examined under 40 high-power field. Cases were divided into low-grade TB and high-grade TB groups according to the median bud count. Results Among the 153 patients with GAC, 51 underwent simultaneous observation of ITB and PTB, which were found to have a significant positive correlation. A higher grade of ITB in tumours was associated with positive lymph node metastasis and could predict a worse prognosis. Additionally, patients with simultaneous PTB and ITB had a shorter overall survival than those with PTB alone, suggesting a worse prognosis. Conclusion PTB and ITB were found to be adverse prognostic factors and high-risk indicators of intestinal-type GAC, and ITB plays an important role in evaluating GAC prognosis in gastroscopic biopsy tissues. Additionally, TB might become a useful index for predicting GAC prognosis in the future.