BACKGROUND: In Egypt, schistosomal infestation is a leading cause of bladder cancer. A mutation in the fibroblast growth factor receptor 3 (FGFR-3) gene is the most common and most specific genetic abnormality in bladder cancer. Similarly, cyclooxygenase-2 (COX-2) is an inducible, pro-inflammatory enzyme with previous studies showing higher expression in schistosomal-associated bladder cancer.
AIM OF THE STUDY: The aim of the study was to evaluate the immunohistochemical expression of FGFR3 and COX2 in bladder carcinoma and correlates their expression to the associated schistosomal infestation to implicate possible therapeutic treatments.
MATERIALS AND METHODS: This retrospective study included a total of 90 cases of archived, formalin fixed, paraffin-embedded tissue blocks that included variable subtypes and grades of urothelial carcinomas. Immunohistochemistry for expression of FGFR-3 and COX2 was performed using a standard avidin-biotin-peroxidase system.
RESULTS: About 73.3% of the total cases (66 cases) showed variable positive reactivity for FGFR3, of which 33.3% (22 cases) were associated with bilharzia infection. A statistically significant correlation was detected between FGFR-3 and tumor size, grade, histologic subtype, LN status, lymphovascular invasion, and stage. About 83.3% of the total cases (75 cases) showed variable positive immunoreactivity for COX-2, of which 37.3% (28 cases) were bilharzial-associated. A positive correlation was established between COX-2 and grade, concomitant in situ changes and cases associated with bilharzia infection.
CONCLUSION: FGFR-3 can be used as a prognostic marker for low-grade urothelial tumors. Results also portray that COX-2 has an inflammatory inciting role in bladder carcinoma development, especially in patients with a history of schistosomiasis (bilharziasis). Both COX-2 and FGFR-3 should be explored further for its use alone or in combination with conventional treatment, to reduce the recurrence rate and progression of superficial (low grade) tumors.
Positive fibroblast growth factor receptor 3 immunoreactivity is associated with low-grade non-invasive urothelial bladder cancer
