LUGPA’s President-Elect Neal D. Shore, MD, FACS, authored the following article for the USA Today supplement, “The Fight Against Cancer.”
The statistics are staggering: bladder cancer is the fifth-most commonly occurring cancer in the United States; approximately 77,000 new cases will be diagnosed in 2016.
Most commonly, blood in the urine (hematuria) is the presenting symptom of bladder cancer. The majority of cases do not penetrate deeply within the bladder wall, however, and thus only very rarely will spread (metastasize). Of note, low-grade bladder cancer lesions may often recur, despite attempted biopsy removal, in about 50 to 80 percent of patients after their initial treatment.
An expensive diagnosis
As it requires lifelong surveillance, bladder cancer thus becomes one of the most expensive cancers to treat on a per-patient basis. It is estimated that $4.1 billion is spent each year to treat bladder cancer in the United States alone. With this ongoing requirement for interventional patient procedures (cystoscopy, tumor resection, anesthesia, etc.) there is an ongoing significant burden on patient care and the health care economy.
Accordingly, early diagnosis and effective surveillance and treatment strategies are key components to the treatment of bladder cancer. It is important that we continue to identify alternative diagnostic tools which are less invasive than cystoscopy, yet remain effective in evaluating the findings of hematuria for both initial and recurrent bladder cancer.
“It is estimated that $4.1 billion is spent each year to treat bladder cancer in the United States alone.”
Getting less invasive
While the current diagnostic pathway for bladder cancer includes several options, the gold standard is still cystoscopy, which is an invasive procedure and may be associated with varying degrees of discomfort and anxiety for the patient. This “cystophobia” has led to the subsequent development of other less invasive diagnostic tests.
Some of the currently available urine-based tests have been limited by subjective interpretation, and their respective low specificity and sensitivity. The limited statistical value of these tests is exacerbated by an additional high rate of equivocal or atypical results. Hence, there exists an opportunity for an objective, non-invasive genomic diagnostic test, which could provide a meaningful improvement for both the initial evaluation, as well as the ongoing assessment for recurrent bladder cancer.
Genomic test efficiency
Recent advances in urine-based testing have led to the development of non-invasive genomic tests for the diagnosis of bladder cancer. As the genomic tests are based on detecting a specific gene signature from bladder cancer tumors, they are objective tests that have demonstrated high rates of sensitivity and specificity. Clinical trials have shown that these tests have high negative predictive values (over 97 percent) while simultaneously being able to identify 97 percent of high-grade tumors. In addition, genomic tests have been shown to be very effective at diagnosing upper tract tumors.
Early diagnosis and effective surveillance should improve cure rates, enhance survival, decrease unnecessary procedures, and lessen the health economic burden of bladder cancer. Genomic diagnostic tests can play a valuable role in this effort either as an adjunct to cystoscopy, or perhaps as an alternative to cystoscopy in appropriate patients. As genomic tests have been developed to optimize patient evaluation and management across the entire continuum of bladder cancer pathology, genomic tests will continue to have an important role in the diagnosis and surveillance for the U.S. bladder cancer population.