Early results of bladder-cancer screening in a high-risk population of heavy smokers.

OBJECTIVE: To report first results of an early bladder-cancer detection programme, and to evaluate the detection rate and the diagnostic value of the tests used. SUBJECTS AND METHODS: Urine samples of 183 screened subjects with a history of smoking of > or =40 pack-years were collected for analysis with a urinary dipstick test for haematuria, the nuclear matrix protein-22 test (BladderChek, Matritech, Inc., Newton, MA, USA), voided urine cytology and a molecular cytology test (UroVysion, Abbott Molecular Inc., Des Plaines, IL, USA). Participants with at least one positive test result had a further evaluation including cystoscopy and radiological imaging. The subjects' risk factors, test results and histological findings were analysed.
RESULTS: In all, 75 subjects had at least one positive test result and were evaluated further; abnormal histological findings were detected in 18 (24% of those who had cystoscopy, 9.8% of the original 183), 15 of those in the urinary bladder, with pTaG1 (one), carcinoma in situ (two), dysplastic lesions (11) and one an inverted papilloma. In the upper urinary tract, two urothelial tumours (pTaG1 and pTxN2G3) and one renal cell carcinoma (pT1G2) were detected by computed tomography. In summary, six of 183 subjects (3.3%) had a histologically confirmed malignant tumour and another 12 (6.6%) were identified with a possible pre-cancerous lesion of the urinary tract. The urinary dipstick, BladderChek, cytology and UroVysion detected (i.e. were true-positive in) nine (50%), one (6%), seven (39%) and 11 (61%) of the 18 tumours found, while they failed to detect nine (50%), 17 (94%), 11 (61%) and seven (39%) of these lesions, respectively. Omitting the urine dipstick test, the BladderChek, cytology or UroVysion from the test setting could have spared 40, five, two or one subjects(s) from unnecessary invasive interventions; however, three, none, two or six lesions, would have been missed. More positive screening tests per subject was associated with a higher probability of a (pre)-malignant lesion.
CONCLUSION: Screening a high-risk group with a history of smoking of > or =40 pack-years showed a significant proportion (3.3%) with malignancy. These first results are encouraging and warrant continuation of the screening programme. In this series the most efficient screening tool was the combination of UroVysion, cytology and urinary dipstick testing. Of special scientific interest will be the follow-up of those patients with a possible pre-cancerous lesion.