The risk of the disease in the future was assessed by analyzing the presence of mutations in 10 genes. (Photo: reproduction)
The researchers first tested the test’s effectiveness on urine samples from participants in the Golestan Cohort Study, which gathered data from more than 50,000 people. After ten years of follow-up, 40 volunteers were diagnosed with bladder cancer. The new test was applied to samples from 29 of these participants and to 98 samples from other participants, which could be used as controls.
The results showed that the test could predict future bladder cancer with 66% effectiveness, 12 years before clinical diagnosis. With 7 years in advance, the effectiveness rose to 86%. In the control population, the test was exactly negative in 96% of patients who did not develop cancer in the future.
Test validation was performed on 70 bladder cancer patients and 96 controls from Massachusetts General Hospital and Ohio State University. These samples were collected prior to the cystoscopy but on the day the patients received their diagnosis. Genetic mutations were identified in samples from 71% of participants whose tumors were detected during cystoscopy. Precision for negative results was 94%.
The results were consistent both in individuals with known risk factors for bladder cancer undergoing cystoscopy and in those with no evidence of disease. Risk factors for this type of tumor include genetics, smoking, or environmental exposure to known carcinogens.
“Research of this nature is very encouraging as it shows that our ability to identify molecular changes in liquid biopsies such as urine that may indicate cancer is constantly improving,” commented Joost Boormans, urologist at Erasmus University Medical Center in Rotterdam, the Netherlands, in a statement.
Despite the promising results, Boormans does not believe this type of test will be used to perform mass screening for bladder cancer. Rather, the test is more likely to be used in high-risk patients or to assess the risk of recurrence in patients who already have the disease.
Bladder cancer occurs mainly in older people, about 90% of patients with this type of cancer are older than 55 years, with an average age of 73 years at diagnosis.
There are three types of bladder cancers. They are divided into the cell types where the tumor starts. The non-invasive ones have not yet invaded deeper layers. Invasive cancers are more likely to spread and more difficult to treat.
The main symptom of the disease is associated with changes in the urine, the first of which is the presence of blood. Other symptoms include urinating more frequently than usual, a feeling of pain or burning, an urge to urinate even when your bladder is not full, and a weaker than normal urinary stream.
In more serious cases, the symptoms can advance and cause other types of manifestations, such as the closing of the urinary canal and consequently the impossibility of the person to urinate, lumbar pain, loss of appetite, weakness, swelling in the feet and legs, bone pain, loss of weight loss, and even a decrease in the functioning of the kidneys.
Risk factors for developing the disease include genetics, exposure to radiation therapy, medications, and other substances; age – the disease is more common after the age of 40 -; drink little liquid; chronic bladder inflammation and smoking.
Treatment varies according to the degree of the disease, and may include surgery, chemotherapy and radiotherapy.