Therapy of low-grade nonmuscle-invasive bladder cancer

Nonmuscle-invasive bladder cancer (NMIBC) comprises a very heterogeneous group of malignancies; the biological behavior of these tumors depends primarily on their grading. Low-grade NMIBC are characterized by a high propensity for recurrence but a very low risk for progression to muscle invasion or metastatic disease. Thus, the first line goal of diagnostic procedures and therapy is reliable visualization and complete resection of all foci. Cytology and other urine-based markers fail due to insufficient sensitivity. A second resection might be necessary only in selected intermediate risk cases; the positive effect of maintenance instillation protocols beyond a single postoperative instillation is questionable for the majority of patients. Risk stratification, e.g., according to the EORTC or EAU proposals, also makes sense in low grade NMIBC.