Bladder Cancer Screening in a High Risk Asymptomatic Population Using a Point of Care Urine Based Protein Tumor Marker

Purpose: We evaluated whether screening high risk asymptomatic individuals with a bladder tumor marker can lead to earlier detection and resultant down staging of bladder cancer. Materials and Methods: Subjects at high risk for bladder cancer based on age and smoking or occupational status were solicited from 2 well patient clinics from March 2006 to November 2007. NMP22® BladderChek® testing was performed on voided urine samples. Those with positive test results underwent office cystoscopy and cytology testing. Participants were contacted for followup at 12 months after study enrollment to evaluate for unrecognized bladder cancer. Results: A total of 1,175 men and 327 women underwent BladderChek testing. Mean participant age was 62.5 years (range 46 to 92). Based on 10-year or greater smoking history 1,298 participants were enrolled while 513 were enrolled based on a greater than 15-year high risk occupation for bladder cancer. Positive BladderChek testing was observed in 85 (5.7%) participants and 69 agreed to undergo cystoscopy. Three types of lesions were diagnosed including multifocal, high grade Ta (1); Ta, low grade tumor (1) and marked atypia (1). Followup was available in 1,309 subjects. Mean followup was 12 months (range 0.9 to 25.5) and 2 of 1,309 participants had low grade noninvasive bladder cancer. Evaluation of patient records revealed that 73.4% of participants had urinalysis within 3 years before screening. Conclusions: NMP22 BladderChek for screening an asymptomatic, high risk population can detect noninvasive cancers but the low prevalence of bladder cancer in this population did not permit assessment of intervention efficacy. Frequent use of urinalyses in high risk persons may attenuate future efforts to study the effects of bladder cancer screening tests.