Significance of Vascular Endothelial Growth Factor Expression in the Bladder Urothelial Carcinoma and Its Association with Tumor Grade and Invasiveness

Iran J Pathol. 2021 Fall;16(4):362-369. doi: 10.30699/IJP.20201.138671.2518. Epub 2021 Jul 6.

Abstract

Background & objective: Vascular Endothelial Growth Factor (VEGF) is one of the newer molecular markers that acts as a central mediator of tumor angiogenesis and is essential for tumor growth, progression, and metastasis. So anti-angiogenic drugs can be used as anticancer therapy. Treatments with anti-VEGF (Bevacizumab) therapy have been proved to improve relapse-free survival in many tumors. Urinary bladder tumor has become emerging cancer globally among elderly individuals. So, the identification and development of novel biomarkers for effective treatment of urinary bladder carcinoma is essential. The present study aimed to investigate the immunohistochemical expression of VEGF in urothelial carcinoma of urinary bladder and to assess its association with tumor grade and muscle invasiveness.

Methods: This cross-sectional study was conducted in the Department of Pathology, Chittagong Medical College, Chattogram from September 2018 to August 2020. Fifty-six formalin-fixed paraffin-embedded tissue blocks of urinary bladder carcinoma were prepared for both histopathological and immunohistochemical examination. Each slide was evaluated by at least two pathologists.

Results: Weak to strong positive expression of VEGF were observed in 52 cases (92.86%). The proportion of tumors positive for VEGF expression was higher among patients with high grade and non-muscle invasive bladder carcinoma.

Conclusion: We found that VEGF expression has a significant association with tumor grade and an inverse association with muscle invasion. These findings may be useful for selecting the subset of patients likely to respond to anti-VEGF targeted therapy.

Keywords: Angiogenesis; Bevacizumab; Muscle-invasion; Urothelial carcinoma; Vascular endothelial growth factor.