Human epidermal growth factor receptor 2: a significant indicator for predicting progression in non-muscle-invasive bladder cancer especially in high-risk groups.

PURPOSE

Current pathological and clinical parameters provide important prognostic information. However, they are still limitations for predicting the true malignant potential of a specific cancer. The aim of this study was to validate the predicting role of HER-2 expression and demonstrated that combination of the high-risk factors with HER-2 expression is more valuable for determining which non-muscle-invasive bladder cancer (NMIBC) is more aggressive.

MATERIALS AND METHODS

In total, 238 patients treated by transurethral resection of the bladder tumor were histopathologically confirmed to be NMIBC. Two experienced uropathologists re-reviewed the slides. HER-2 expression was evaluated by immunohistochemistry and scored for intensity and area of staining. The association of HER-2 staining with tumor recurrence and progression was evaluated by univariate and multivariate analyses and Kaplan-Meier survival curves.

RESULTS

In multivariable analyses, HER-2 expression was an independent risk factor for predicting tumor progression (HR 2.64, p = 0.024). Combining the EORTC risk scores with HER-2 expression status led to more accurate prediction of progression, especially in patients with intermediate- and high-risk EORTC scores (p < 0.0001, log-rank test).

CONCLUSIONS

HER-2 positivity is prognostic for predicting progression to muscle invasion in NMIBC. Combination of the high-risk factors with HER-2 expression is more valuable for determining which NMIBC is more aggressive.