Utility of the BTA stat test kit for bladder cancer screening

Our study evaluated the BTA (bladder tumor antigen) stat test kit as a primary screening device for the detection of transitional-cell carcinoma (TCC) of the bladder, with direct comparison by voided urine cytology (VUC) on the same specimens. The unfixed voided urine of 100 patients with no history of bladder cancer who had signs and symptoms of dysuria, incontinence, and gross hematuria and microhematuria were tested using the one-step BTA stat test kit before processing via the cytospin technique for fluid cytological evaluation. The patients in the study were followed for up to 12 mo with repeated urine cytological testing, cystoscopy, and bladder biopsy when clinically indicated. Nineteen cases tested positive, and 81 cases tested negative on the BTA stat test. VUC diagnosed three cases as unequivocally positive for TCC, 93 cases as negative, and four cases in which unqualified atypical urothelial cells were noted. TCC was confirmed by cystoscopy and bladder biopsy in three of three cases diagnosed by VUC and in three of 19 cases that tested positive by the BTA stat test. These findings resulted in an 84% false-positive rate for the BTA stat test and no false-positive cases for VUC during the 12-mo follow-up period. The results indicate that the sensitivity and specificity of BTA stat test are comparable to those of VUC; however, owing to a relatively high false-positive rate, it can at best act as an adjunct to urine cytological study for bladder cancer screening.