Value of intravesical sonography in tumor classification of bladder carcinoma

The possibility of a T classification for bladder carcinoma by intravesical sonography was investigated in a 3-year field study (1982-1985) at the Urological Clinic, Bonn University. In a total of 571 patients with histologically verified bladder cancer, the sonographic classification was compared with the histological T category. There was an agreement of 70.1%. While the infiltration of superficial tumors (above all of large tumors) was frequently overestimated (28.7%), understaging predominated in invasive carcinomas (20.9%). The overall precision of conventional staging techniques was 67%. Ultrasonography showed a marked superiority, above all in infiltrative papillary tumors of low diameter (precision 76% compared to 12% with the conventional T classification). The sensitivity of the method with regard to the detection of tumor infiltration (90%) was also markedly higher than that of earlier techniques (66%). Particularly helpful in the evaluation of more deeply infiltrating tumors, intravesical sonography constitutes a major extension of the diagnostic spectrum for T classification of bladder carcinoma.