Background: Targeted and immunotherapy got approval to treat locally
advanced and/or metastatic urinary bladder (UB) cancer in specific situations.
Human epidermal growth factor receptor 2 (HER2) expression is certified in UB
cancer but with controversial results regarding the impact of targeted therapies
on survival. This study explored expression of HER2 protein in UB cancer
patients in our locality and its correlation with clinical outcomes.
Methods: One hundred-thirty two samples of UB cancer collected and tested
for HER2 receptor expression using immunohistochemistry (IHC) analysis.
Together with patients medical records from 2012 through 2016 used analyze its
significance with tumor characteristics and investigate its effect on DFS, PFS
and OS. This work was conducted at Sohag University Hospital and Sohag
Cancer Center. Data was analyzed using STATA intercooled version 16 for
clinic-pathological associations.
Results: HER2 expression was positive in 65% of samples; only pathological
subtype had a significant association with HER expression intensity (p= 0.001).
No significant association found between HER2 expression and other variables
as regards age, tumor size, nodal spread or stage. As regards OS; HER2 positive
expression associated with significant longer cumulative OS (p=0.006) and in
multivariate Cox-regression analysis; it was the only factor associated with
statistically significant longer OS (p=0.04; HR=0.43). No significant association
found in the cumulative or Cox analysis for DFS and PFS (p= 0.79 and p= 0.08
respectively).
Conclusion: in this work; HER2 expression was higher in bladder cancer cases
especially in TCC. Also, patients with HER2 positive protein expression had a
significant longer OS with probability and regression positive effect. No
significant effect on DFS or PFS in the probability or Cox analysis of HER2
expression. However, these findings mandate larger prospective studies with
anti-HER2 agents included in the management of these patients