Purpose: The BTA stat double dagger test is a rapid, noninvasive, qualitati
ve urine test that detects bladder tumor associated antigen (human compleme
nt factor H related protein) in wine. We compared BTA stat test to voided u
rine cytology in patients monitored for bladder cancer in a prospective tri
al, and determined whether this test is effective in detection of recurrenc
e not seen by regular cystoscopy.
Materials and Methods: A total of 445 consecutive patients with bladder can
cer were studied. A voided urine sample was obtained before cystoscopy and
divided for culture, cytology and BTA stat testing. In cases of a positive
BTA stat test but negative cystoscopy, excretory urography or renal ultraso
und, random biopsies and collected ureteral urine samples for ureteral cyto
logy were obtained. The overall sensitivity and specificity as well as posi
tive and negative predictive values for BTA stat test, cytology and their c
ombination were calculated.
Results: Of the 445 patients 118 (26.5%) had bladder cancer recurrence on c
ystoscopy, which was detected by BTA stat test and cytology in 63 (53.4%) a
nd 21 (17.8%), respectively. Of the remaining 327 patients not having recur
rent tumor on cystoscopy 81 (24.8%) had a positive BTA stat test. Excretory
urography or renal ultrasound and random biopsies in 48 (59.3%) of these p
atients revealed 7 recurrences, making the total number of recurrent tumors
125 of 412 (30.3%). The overall sensitivities and specificities for the BT
A stat test, cytology and their combination were 56.0%, 19.2%, 60.0% and 85
.7%, 98.3% and 85.0%, respectively.
Conclusions: The sensitivity for detection of recurrent tumor on BTA stat t
est is superior to that of voided urine cytology in all bladder cancer cate
gories, whereas the specificity of voided urine cytology is higher than tha
t for BTA stat test. However, a sixth of the patients with apparent false-p
ositive BTA stat test results chosen for further investigation had recurren
t tumors that were not found on routine cystoscopy. Although the sensitivit
y and specificity were highest when both tests were used, the differences w
ere not significant overall. Therefore, the BTA stat test could potentially
replace urine cytology for followup of superficial bladder cancer.