FGFR2 and favorable survival outcomes in resected poorly cohesive cell gastric cancer: Analysis from FGFR2 protein overexpression and genetic variation.

Abstract

Poorly cohesive cell gastric cancer has aggressive and heterogeneous characteristics. This study investigated the clinical significance of fibroblast growth factor receptor 2 expression and genetic variations in patients with PCC-GC. We retrospectively collected 209 surgically resected stage II and III PCC-GC cases. After FGFR2 immunostaining, we analyzed clinical data and performed targeted sequencing to assess their impact on patient survival. Among 209 patients, 89 (42.6%) were classified as stage II and 120 (57.4%) as stage III. FGFR2 overexpression varied by stage, with FGFR2 positivity observed in 61.5% of stage II cases, while FGFR2-negative cases were predominant in stage III patients (60.1%) (P = 0.037). Moreover, lymph node involvement was associated with FGFR2 expression (P = 0.009). FGFR2 positivity significantly correlated with improved disease-free survival (DFS) and overall survival and remained an independent favorable prognostic factor for DFS in multivariate analysis (P = 0.022). Targeted next-generation sequencing was performed in five selected cases, FGFR2 amplification or pathogenic alterations were not found. This study shows that FGFR2 expression was independently associated with improved DFS in PCC-GC. These findings suggest that FGFR2 may serve as a prognostic biomarker in patients with PCC-GC.