Testing for gene mutations in urine can predict bladder cancer as early as 12 years: Researchers
Testing for genetic mutations in urine can detect bladder cancer years before the disease shows clinical symptoms, researchers of new multi-country research have found.
The findings of the research, presented during the European Association of Urology (EAU) annual Congress in Milan recently, the researchers from France, Iran and the United States identified mutations across ten genes capable of predicting the most common type of bladder cancer up to 12 years in advance of diagnosis.
Bladder cancer, one of the most common cancers, ranks 10th among all cancers and is the 17th most common cancer in women, according to the World Cancer Research Fund International, a London-based non-profit organisation dedicated to cancer prevention.
According to the organisation, more than 573,000 new bladder cancer cases were diagnosed worldwide in 2020.
It is also worth noting that it is one of the top ten most common cancers in the United Kingdom and the fifth most common in the European Union, with over 200,000 cases reported each year.
According to the researchers, only around half of those diagnosed with the advanced disease will survive more than five years, mainly due to late diagnosis and recurrence of the disease, while detecting these cancers at an early stage increases the survival rates by more than 80% patients for at least five years.
“Having a simpler urine test that could accurately diagnose and even predict the likelihood of cancer years in advance could help to spot more cancers at an early stage and avoid unnecessary cystoscopies in healthy patients,” she added
Based on the UroAmp test, a general urine test that identifies mutations in 60 genes, developed by the Oregon Health Science University spin-out company Convergent Genomics, the researchers of the study drew from findings of previous research to identify genetic mutations linked to bladder cancer, narrowed the new test down to focus on mutations within just ten genes.
At the Tehran University of Medical Sciences in Iran, researchers trialled the new test using samples from the Golestan Cohort Study, which has tracked the health of more than 50,000 participants over ten years, all of whom provided urine samples at recruitment. 40 people within the study developed bladder cancer during that decade, and the team were able to test urine samples from twenty-nine of them. They also tested samples from 98 other similar participants as controls.
Of the 29 participants who had developed bladder cancer within the Golestan cohort, the test was able to accurately predict future bladder cancer in 19 (66%) of them, even though urine samples had been taken up to 12 years before clinical diagnosis, the researchers said.
The researcher further reported that fourteen of these participants were diagnosed with bladder cancer within seven years of urine collection, and the test was able to predict cancer in 12 (86%) of these. The test was accurately negative in 94 of the 98 participants (96%) who would not develop cancer in the future.
Among those where test was negative but who did eventually develop bladder cancer, no cancer was diagnosed until at least six years after the urine collection, the researchers reported.
The trial at Massachusetts General Hospital and Ohio State University used samples from 70 bladder cancer patients and 96 controls, taken before a cystoscopy, where some of these samples were provided by cancer patients on the day they were diagnosed rather than many years before, revealed that mutations were found in urine samples from 50 of the 70 patients (71%) whose tumours were visible during the cystoscopy.
The researchers went on to say that some of these were new diagnoses, while others were cancer recurrences, and that no mutations were found in 90 of the 96 (94%) patients who had a negative cystoscopy.
Dr Le Calvez-Kelm believes these results demonstrate the potential of a genetic urine test for the early detection of bladder cancer.
“We have clearly identified which are the most important acquired genetic mutations that can significantly increase the risk of cancer developing within ten years. Our results were consistent across two very different groups – those with known risk factors undergoing cystoscopy and individuals who were assumed to be healthy,” she said
“Should the results be replicated in larger cohorts, urine tests for these mutations could enable routine screening for high-risk groups, such as smokers or those exposed to known bladder carcinogens through their work,” Dr Le Calvez-Kelm added.
Pointing out that the test could also be used when patients come to their doctors with blood in the urine to help reduce unnecessary cystoscopies, she added, “ If we can identify bladder cancer early on before the disease has advanced, then we can save more lives.”
“Research of this nature is very encouraging as it shows that our ability to identify molecular alterations in liquid biopsies such as urine that might indicate cancer is constantly improving,” Dr Joost Boormans, a member of the EAU Scientific Congress Office and a urologist at the Erasmus University Medical Centre Rotterdam, said.
Emaphasiang that though there is a need to develop more accurate diagnostics, it is unlikely that we will have a mass screening programme for bladder cancer shortly, Dr Boormans added, “Where a urine test for genetic mutations could show its value is in reducing cystoscopies and scans in bladder cancer patients who are being monitored for recurrence, as well as those referred for blood in their urine.”
“A simple urine test would be far easier for patients to undergo than invasive procedures or scans, as well as being less costly for health services,” he further added.
