Evaluation of effect of treatment for invasive bladder cancer by ultrasonography with intra-arterial infusion of carbon dioxide microbubbles.

Abstract

The purpose of this study was to evaluate the diagnostic usefulness of the ultrasonography with intra-arterial infusion of carbon dioxide microbubbles (CO2) for invasive bladder cancer. Twelve patients with muscle-invading bladder cancer who were treated by concurrent radiotherapy and intra-arterial infusion of daily low dose of cisplatin using an implanted infusion port were included. A total of 30 studies was performed during the treatment to evaluate the visualization of the tumor and effect of the treatment compared with conventional ultrasonography, computed tomography, or cystoscopy. Satisfactory visualization of the tumor in CO2 ultrasonography was obtained in all patients, in particular in those with flat tumor or prostatic invasion. The enhancement effect of CO2 on the tumor, which was maintained well in the late period of the treatment, made possible evaluation of the therapeutic effect. With respect to the evaluation of local response, disagreement between clinical response and the evaluation of CO2 ultrasonography was observed in two patients with definite differentiation between wall edema and residual tumor after treatment being difficult. Carbon dioxide ultrasonography is easy to perform in patients treated with arterial infusion therapy using an implanted infusion port and provides practical information in evaluating therapeutic effect.