[Visual diagnosis while performing transurethral resection of bladder tumors: power or myth?]

The gold standard for diagnosis and immediate therapy of bladder cancer is a transurethral resection (TURB) followed by histopathologic evaluation. The aim of this study was to assess the reliability of visual diagnosis by the operating urologist concerning dignity (malignant/benign) and staging compared to histopathologic evaluation. This is especially crucial since early mitomycin C instillation is based on the urologist's first impression.

This prospective study included 311 cases of TURB from five German institutions. Surgeons were asked to estimate dignity of the neoplasm, tumor stage, and grade according to a standardized questionnaire.

The subjective estimation/visual diagnosis of the operating urologist achieved a sensitivity with respect to identifying malignant tumors as such of 97%, while specificity was only 41%. Accordingly, the positive (PPV) and negative predictive values (NPV) were 76% and 88%, respectively. In general, muscle invasive cancer was predicted more often than confirmed by pathology (PPV 52%). However, whenever muscle invasive cancer was excluded by the urologist, this was confirmed by the pathologist in most the cases (NPV 95%). The educational degree did not influence the reliability and predictive value of visual diagnosis.

This study shows that urologists cannot reliably distinguish benign from malignant lesions of bladder mucosa-regardless of their educational degree. A reliable diagnosis of a pathologist is definitely needed to plan final therapeutic steps.