Prognostic Role of Tumor Budding in Carcinoma Tongue: A Systemic Review and Meta-Analysis

Introduction Tumor budding is defined as a cluster of cells that invade the stroma. This has recently been studied to be associated with lymph node metastasis (LNM) and poor overall survival (OS) rate. The reliability and reproducibility of this histopathological feature make it a valid prognostic indicator in tongue carcinomas, which often have an unpredictable prognosis. The objective of this study was to group the studies that elucidate the prognostic role of tumor budding in tongue cancers. Methods A systematic database search was performed in MEDLINE, Embase, and Google Scholar for relevant studies that reported tumor budding in tongue cancer. The relevant articles were independently screened by two authors for selection and data extraction. As a result, a list of such studies, clinical trials, and references, published in English up to March 2020, was obtained, and a total of 1448 patients in nine studies were included in this meta-analysis. Statistical analysis was conducted using RevMan software 5.3 (The Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen). Results A higher tumor budding score was significantly correlated with LNM (hazard ratio (HR): 3.07; 95% confidence interval (CI): 2.08-4.52; p≤.00001) and poor OS (HR: 2.40; 95% CI: 1.84-3.14; p≤.00001) in tongue cancer. Conclusions Our present study demonstrates that tumor budding is an independent predictor of LNM and OS in tongue cancer. Tumor budding should be considered a parameter in future oncological staging systems.