VEGF protein expression in oesophageal cancer and associated clinicopathological and demographic features as seen at the Department of Pathology, Makerere University

Abstract

In 2020, esophageal cancer was the 10th most common cancer worldwide with an estimated 604,100 new cases and the sixth leading cause of cancer death with 544,076 deaths associated with it. Esophageal squamous cell carcinoma is the most prevalent type of esophageal cancer worldwide. Esophageal adenocarcinoma is the most common type in developed countries. According to GLOBCAN 2020, the incidence of esophageal cancer in Uganda among males and females was 8.9% and 4.2%, respectively. Vascular Endothelial Growth Factor (VEGF), a signal protein produced by cells that stimulates the process of angiogenesis, has been shown to be expressed in esophageal carcinoma tumor tissue. Studies in developed countries have found it to be associated with a poor prognosis. Currently, no study has described the expression of VEGF in esophageal cancer in Uganda. Objective: To describe VEGF protein expression in esophageal cancer and associated clinicopathological features as seen at the department of Pathology, Makerere University, Kampala, Uganda. Method: The study was a cross sectional laboratory-based study. Formalin-fixed and paraffin-embedded (FFPE) tissue blocks of patients diagnosed with esophageal cancer at the department of Pathology, Makerere University, from January 2011 to December 2021 were used. Convenient sampling was used to include tissue blocks in the study, and a sample size of 110 FFPE blocks meeting the inclusion criteria was used. Sections from each case were stained using Hematoxylin and Eosin (H&E) and Immunohistochemistry (IHC) staining for VEGF in accordance with the standard operating procedures.

Data extraction forms were used to capture variables, that is, age, sex, tumor histological subtype, grade, and VEGF protein expression, and then analysis was done using STATA version 14. For measures of association, Chi square tests with 95% confidence interval was used, and a p-value of less than 0.05 was considered statistically significant. Results The mean age of patients from whom specimens had been collected was 59 years, with a standard deviation of 11 years. Most of the patients were males, 71 (64.6%). The majority of the specimens were of conventional squamous cell histological type, 101 (91.8%) and of moderately differentiated histological grade, 58 (52.7%). The prevalence of VEGF expression was 51.8% (57/110). There was no statistically significant association between VEGF expression and age, histological type, or grade of esophageal carcinoma. Conclusion There is a 51.8% expression of VEGF among tissue blocks of esophageal cancer archived at the Department of Pathology, Makerere University, Kampala, Uganda. There is no association between VEGF protein expression and demographic factors, histopathological features of esophageal carcinoma such as age, sex, histological grade, or histological type in the sample.