Human epidermal growth factor receptor 2 expression is more important than Bacillus Calmette Guerin treatment in predicting the outcome of T1G3 bladder cancer

Abstract

In the present study we tested the role of Human Epidermal Growth Factor Receptor-2 (HER-2) expression, as assayed by immunohistochemistry, in predicting recurrence and progression in 67 patients with T1G3 BC having undergone transurethral resection of bladder tumor (TURBT) alone (33) or TURBT + Bacillus Calmette Guerin (BCG) instillations (34). All patients had a negative restaging TURBT within 4 months after the first TURBT. At median follow-up of 75.7 months, the overall disease-free and progression-free rates were 35.8% and 73.0%, respectively. Univariate Kaplan-Meier survival analysis showed that traditional prognostic factors (sex, tumor number/size/recurrence) failed to predict disease-free and progression free survival (DFS, PFS). BCG treatment was a significant predictor of DFS (p=0.0231) but not of PFS (p=0.6901). HER-2 overexpression was a significant predictor of DFS (p=0.0013) and PFS (p=0.0322) in the overall patients population, but failed to predict PFS when patients were stratified for treatment (BCG: p=0.1290; no BCG: p=0.1696) probably due to the limited number of events. Multivariate Cox proportional-hazards regression analysis confirmed that BCG treatment was a significant predictor of DFS (p=0.012) but not of PFS (p=0.924), whereas HER-2 overexpression was a significant predictor of DFS (p=0.001) and PFS (p=0.041). These findings suggest that HER-2 status performs better than “traditional” prognostic factors as well as of BCG treatment in predicting the outcome of T1G3 BC, thus providing grounds for further testing this marker and possibly incorporating it in a panel of molecular markers that could reliably predict the behavior of this challenging disease.