Men with lower urinary tract symptoms involving dysfunction in voiding, or voiding and storage, are at higher risk of bladder cancer than men without these forms of urinary dysfunction, according to a study recently published in Urology.1 The voiding dysfunction most strongly associated with bladder cancer risk was frequent urinary hesitancy; authors also observed a stronger link between lower urinary tract symptom severity and noninvasive bladder cancer compared with invasive bladder cancer.
“The different observations with noninvasive and invasive are difficult to interpret,” lead investigator Dominique Michaud, ScD, told Urology Practice Management. “We tried to address the possibility of detection bias—that is, that symptoms result in [more urological testing and in turn] more diagnosis of noninvasive cancers—but it was unclear that it was all detection bias.”
Dr Michaud, Professor of Public Health and Community Medicine, Tufts University School of Medicine, Boston, and colleagues believe that if these findings are confirmed, lower urinary tract symptoms could be used to identify men who may be at higher risk of bladder cancer.
The researchers used data from 30,183 men in the Health Professionals Follow-Up Study—an ongoing study initiated in 1986 to evaluate hypotheses about men’s health—from years 1992, 1994, 1998, and 2000. They examined the associations between bladder cancer risk and forms of lower urinary tract symptoms in a multivariate analysis that adjusted for age, total fluid intake, intake of fruits and vegetables, intake of bacon, smoking status, pack-years of smoking, and diabetes status.
The results indicated that compared with no lower urinary tract symptoms, voiding dysfunction and mixed voiding–storage dysfunction were significantly associated with elevated risk of bladder cancer, with relative risks (RRs) of 1.58 and 1.87, respectively. This result was demonstrated using analysis that ruled out symptoms that may have developed as a result of diagnosed cancer.
Results also demonstrated that men who have urinary hesitancy ≥50% of the time have a 2.21-fold elevated risk for bladder cancer compared with men who have no urinary hesitancy. The investigators showed in a separate analysis that men with urinary hesitancy ≥50% of the time also have the highest overall American Urological Association Symptom Index score among all men who experienced any of 7 types of urinary symptoms ≥50% of the time.
No other categories of urinary symptoms were significantly associated with bladder cancer. Furthermore, when the first 2 years of follow-up data were excluded to rule out symptoms occurring in patients who had been diagnosed with bladder cancer, there was a significantly elevated risk of noninvasive bladder cancer among men with mixed voiding–storage dysfunction, with an RR of 3.36. Associations were also significant between moderate lower urinary tract symptoms and severe lower urinary tract symptoms and noninvasive cancer, with RRs of 1.87 and 2.62, respectively.
An analysis that excluded the first 4 years of follow-up data uncovered elevated risks for noninvasive bladder cancer in men with mild lower urinary tract symptoms (RR = 2.69), storage dysfunction alone (RR = 2.99), and mixed voiding–storage dysfunction (RR = 6.08). Dr Michaud and colleagues noted that the results fit with the fact that voiding dysfunction leads to extended contact time between potential carcinogens in the urine and the cells lining the bladder.
“Results suggest that the presence of severe urinary hesitancy might indicate higher volume of postvoid residual urine, which can increase the contact time of potential carcinogens in urine and the bladder urothelium and the risk of bladder cancer,” they concluded.
- Zhou J, Kelsey KT, Smith S, et al. Lower urinary tract symptoms and risk of bladder cancer in men: results from the Health Professionals Follow-Up Study. Urology. 2015 Apr 8 [Epub ahead of print].