Can gemcitabine instillation ablate solitary low-risk non-muscle-invasive bladder cancer? Results of a phase II marker lesion study.

Purpose: The purpose of this phase II study was to evaluate whether low-risk non-muscle-invasive bladder cancer can be ablated with intravesical gemcitabine in a marker lesion study.

Patients And Methods: The study had a Simon II-stage design. Thirteen patients were to be recruited for stage I. In the event of ≥4 responses, another 30 patients were to be recruited. Patients were given gemcitabine 2,000 mg intravesically once per week for 6 weeks and the response was assessed with endoscopic, histological, and urine cytological findings.

Results: Fourteen patients evaluated for efficacy completed the study; complete responses were achieved by 2 patients (14.3%), both of these patients had lesions of <1 cm. Eleven patients (78.6%) were non-responders and 1 patient (7.1%) had progressive disease. Since the response rate in stage I was below the minimal pre-defined limit, the study was stopped.

Conclusions: This study shows that intravesical gemcitabine does not merit further study in this patient population. A tumor size of >1 cm may be a critical factor in accounting for the low response rate.