title: Analysis of false-positive BTA STAT test results in patients followed up for bladder cancer.
abstract: OBJECTIVE
  To evaluate the role of a positive BTA stat Test result in patients with negative cystoscopic findings.
  
  
  METHODS
  Five hundred one consecutive patients in follow-up for bladder cancer were studied. A voided urine sample was obtained before cystoscopy and split for culture, cytology, and BTA stat testing. In the case of a positive BTA stat Test, but negative cystoscopic findings, patients underwent additional investigations.
  
  
  RESULTS
  Of 501 patients, 133 (26.5%) had bladder cancer recurrence at cystoscopy, of which the BTA stat Test detected 71 (53.4%); only 21 of the cases (17.9%) were detected by cytologic examination. Of the remaining 368 patients with no visible tumor at cystoscopy, 96 (26.1%) had a positive BTA stat Test result. Fifty-five of those (57.3%) underwent intravenous urography or renal ultrasound and random biopsies, and an additional 9 recurrences (16.4%) were detected. Of those 46 patients who had a true false-positive BTA stat Test, 3 (3 of 43, 7.0%) had recurrence at the next follow-up cystoscopy, 4 (8.7%) had a urine infection, and 8 (17.4%) had ongoing intravesical instillations; the latter two percentages were significantly higher than among those with true-negative BTA stat Test results (0% and 6.8%, respectively).
  
  
  CONCLUSIONS
  Patients with a positive BTA stat Test result but negative cystoscopic findings have about a 16% risk of an undetected recurrence. False-positive results may be due to present instillation treatment and urine infection, and the predictive value of a BTA stat Test for subsequent recurrence seems relatively low.
authors: Division of Urology, Department of Surgery, Tampere University Hospital, Tampere, Finland.
authors: M P
authors: MP
authors: Raitanen
authors: E
authors: E
authors: Kaasinen
authors: O
authors: O
authors: Lukkarinen
authors: R
authors: R
authors: Kauppinen
authors: J
authors: J
authors: Viitanen
authors: T
authors: T
authors: Liukkonen
authors: T L
authors: TL
authors: Tammela
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm / Q000652:urine*; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis / Q000652:urine; D003558:Cystoscopy; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000652:urine*; D009367:Neoplasm Staging; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000652:urine*; D014556:Urine / Q000166:cytology*
chemical_list: D000951:Antigens, Neoplasm