Urine test detects bladder cancer up to 10 years before clinical signs
A compelling new study from the World Health Organization’s International Agency for Research on Cancer (IARC) is suggesting a simple biomarker in urine may be an effective predictive test for bladder cancer, signaling the disease's presence up to 10 years before clinical signs appear.
Bladder cancer is a challenging type of cancer to catch in its early stages. The best diagnostic technique currently available is an invasive imaging procedure called cystoscopy. Several urine-based biomarkers are currently under investigation but none have been clinically verified to the point they are widely recommended. And even then, these urine-based tools may only be effective in surveilling active cases and not detecting early instances of the disease.
For several years researchers have known mutations in the telomerase reverse transcriptase (TERT) gene are incredibly common in many cases of bladder cancer. These TERT mutations can be detected in urine samples but until now it hasn’t been clear whether this biomarker is an effective early detection tool.
To investigate this possibility, the IARC scientists collaborated with a team of Iranian researchers working on a long-term research project called the Golestan Cohort Study. The project began in 2004, recruiting over 50,000 healthy subjects for a long-term health study. A bio-specimen bank of blood, urine, hair and nail samples was created at the beginning of the project, offering researchers a valuable baseline for study.
“With the collection of urine samples at enrolment for 50,045 Iranian individuals and a follow-up of more than 10 years, the Golestan Cohort study is one of the few prospective population-based cohorts that provide the opportunity to asses urinary biomarkers for the pre-clinical detection of bladder cancer,” explains Reza Malekzaded, co-senior author on the new study, and principal investigator of the Golestan Cohort Study.
From the study cohort, 38 individuals ultimately went on to develop bladder cancer and TERT mutations could be detected in 46.7 percent of these subjects. And perhaps even more importantly, no TERT mutations were detected in a control group of 152 matched cancer-free subjects.
“Our results provide the first evidence from a prospective population-based cohort study of the potential of urinary TERT promoter mutations as promising non-invasive biomarkers for the early detection of bladder cancer,” says Ismail Hosen, co-first author on the study.
The researchers do admit this is an early pilot study, with a small cohort of bladder cancer subjects, so the predictive nature of TERT mutations will need further verification before it even comes close to clinical use. However, this is an extraordinarily promising, simple, and inexpensive test for bladder cancer that, if validated in larger studies, could offer clinicians a valuable new tool in catching this cancer at its earliest stages.
The new research was published in the journal EbioMedicine.