Clinical Significance of BTA Stat Test in the Diagnosis of Bladder Cancer

Kim, Sun Il; Chung, Byung Ha; Hong, Sung Joon

Abstract

PURPOSE: We compared the sensitivity and specificity of BTA stat test with those of voided urine cytology and bladder washing cytology in the detection of bladder cancer.
MATERIALS AND METHODS
Voided urine samples were obtained from 114 persons and were tested for BTA stat test. Cytology was performed with the same urine of those who were suspected of having bladder cancer and those on follow-up after treatment of bladder cancer. Cytology reports of either class IV or V were considered positive. Cystoscopy and bladder washing cytology were performed subsequently.
RESULTS
Cystoscopy revealed bladder cancer in 34 patients. Overall sensitivity of BTA stat test was 88% versus 41% of voided urine cytology (p<0.001). BTA stat test was more sensitive than bladder washing cytology in a subset of 24 patients by 88% to 58% (p<0.05). Specificity of BTA stat test was 74% in 39 persons who were either healthy (10) or had urologic diseases other than bladder cancer (29). Specificity was 61% versus 95% of voided urine cytology in 41 follow-up patients without gross evidence of recurrence(p<0.001). Four patients had both false positive BTA and cytology: 2 received TURB for recurrent bladder cancer 6 months later and the others showed repeated positive cytology without evidence of recurrence 3 and 6 months later.
CONCLUSIONS
BTA stat test is superior to cytology (voided and washing) in detecting bladder cancer, but is not reliable enough to substitute cystoscopy. It may somehow allow some flexibility to a strict follow-up cystoscopy schedule in carefully selected cases. Longer follow-up is needed with false positive cases to determine whether BTA stat test is capable of predicting recurrence.