[Intravesical radioimmunotherapy of carcinoma in situ of the urinary bladder after BCG failure].

Background: In failure to respond to bacillus Calmette-Guérin (BCG) in patients with carcinoma in situ (CIS) of the urinary bladder, radical cystectomy remains the mainstay after BCG failure.

Objectives: The aim of this pilot study was to evaluate tolerability and safety of the α‑emitter radioimmunoconjugate instillation in patients after BCG failure.

Materials And Methods: Nine patients were included. After emptying the bladder via a transurethral catheter, Bi-213-anti-EGFR-mAb was instilled. Treatment was terminated by emptying of the radioimmunoconjugate from the bladder 120 min after instillation. Efficacy was evaluated via endoscopy and histology 6 weeks after instillation.

Results: All patients showed excellent toleration of the treatment without any side effects. Treatment resulted in complete eradication of tumor cells in 3 patients and persistent tumor detection in the other 6 patients.

Conclusions: Intravesical instillation of Bi-213-anti-EGFR-mAb is a promising therapeutic option for treatment of in situ bladder cancer after BCG failure for patients who wish to preserve the bladder.