Evaluation of a bladder tumor antigen test for the diagnosis of lower urinary tract malignancies in dogs

Objective-To evaluate the use of a human bladder tumor antigen test for diagnosis of lower urinary tract malignancies in dogs. Sample Population-Urine samples from dogs without urinary tract abnormalities (n = 18) and from dogs with lower urinary tract neoplasia (20) or nonmalignant urinary tract disease (16). Procedure-Test results were compared among groups and among 3 observers. The effects of urine pH and specific gravity, degree of hematuria, and storage temperature and time of urine samples on test results were also assessed. Results-Test sensitivity and specificity were 90 and 94.4%, respectively, for differentiating dogs with lower urinary tract neoplasia from dogs without abnormalities. However, specificity decreased to 35% for differentiating dogs with neoplasia from dogs with nonmalignant urinary tract disease. In dogs with neoplasia, results were significantly affected by degree of hematuria. However, addition of blood to urine from dogs without hematuria had no significant effect on test results. Although intraobserver variation was significant, urine pH, specific gravity, or storage time or temperature had no significant effect on results. Conclusions and Clinical Relevance-Although this bladder tumor antigen test was sensitive for differentiating dogs with malignancies of the lower, urinary tract from dogs without urinary tract disease, it was not specific for differentiating dogs with neoplasia from dogs with other lower urinary tract abnormalities. It cannot, therefore, be recommended as a definitive diagnostic aid for the detection of lower urinary tract malignancies in dogs.