Prognostic importance of FGF2 and FGFR1 expression for patients affected by ameloblastoma

BackgroundFibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) have been investigated in different human neoplasms and were shown to play important roles in the pathogenesis of these diseases; however, very few are known regarding their prognostic importance in the context of ameloblastoma. Therefore, the aim of this study was to investigate whether the expression of FGF2 and FGFR1 is associated with ameloblastoma clinical behavior. MethodsFifty-eight cases of ameloblastoma arranged in tissue microarray were submitted to immunohistochemistry against FGF2 and FGFR1. Clinicopathological parameters regarding sex, age, tumor size, duration and location, treatment, recurrences, radiographic features, cortical disruptions, and follow-up data were obtained from patients' medical records and correlated with the molecules expression. Univariate and multivariate Cox regression analyses were used to investigate the prognostic potential of the biomarkers. ResultsForty-four cases (75.9%) exhibited cytoplasmic positivity for FGF2 in central and peripheral epithelial cells, 46 of 58 (79.3%) showed FGFR1 cytoplasmic positivity predominantly in the columnar peripheral cells, and 43 cases (74.1%) were positive for both. Expression of FGF2 and FGF2+FGFR1 was associated with tumor recurrences (P=.05). However, univariate and multivariate analyses did not demonstrate a significant influence of FGF2, FGFR1, or FGF2+FGFR1 in the 5-year disease-free survival (DFS) rate (P=.27, P=.33, and P=.25, respectively). ConclusionCytoplasmic expression of FGF2 and FGF2+FGFR1 is associated with ameloblastoma recurrence, but FGF2 and FGFR1 are not determinants of a lower DFS.