Clinicopathological and prognostic significance of VEGF, PDGF-B, and HER2/neu expression in gallbladder cancer.

AIM: Gallbladder cancer (GBC) is usually diagnosed in advanced stages with poor survival. The molecular mechanisms of GBC still remain unexplored. Several angiogenesis factors play a pivotal role in tumor progression. We aimed to study the expression of VEGF, PDGF-B, and human epidermal growth factor receptor 2 (HER2/neu) and its association with clinicopathological features and survival in GBC.

MATERIALS AND METHODS: VEGF, PDGF-B, and HER2/neu expression was studied by immunohistochemistry (IHC) after histological evaluation in 91 GBC cases. The relationship between these markers and clinicopathological features and survival was explained through the Cox regression model and Kaplan-Meier method.

RESULTS: VEGF, PDGF-B, and HER2/neu overexpressed in 45, 79, and 68% GBC cases, respectively. VEGF was significantly overexpressed in GBC without gall stones (GS) (p = 0.007) and with moderately and poorly differentiated tumors (p = 0.012). HER2/neu was significantly overexpressed in GBC with GS (p = 0.022). Median overall survival (OS) was 39 months (95% CI: 23-55). In univariate analysis, histological type (adenocarcinoma and papillary) vs. others (signet ring/mucinous/adenosquamous) (p = 0.004), depth of tumor infiltration (p = 0.017), distant metastasis (p = 0.012), and adjuvant therapies (chemotherapy/radiotherapy) (p = 0.083) were associated with poor prognosis. Multivariate survival analysis showed histological type (p = 0.004) and distant metastasis (p = 0.032) to be independent prognostic factors for OS. Histological type (p = 0.002), distant metastasis (p = 0.003), and depth of tumor infiltration (T3-T4) (p = 0.012) showed poor median survival. Poor survival was seen in VEGF and HER2/neu positive cases.

CONCLUSION: Overexpression of VEGF, PDGF-B, and HER2/neu might be possible prognostic biomarkers in GBC. Poor survival of VEGF and HER2/neu positive cases indicates the possibilities of using their blockers as therapeutic agents.