Globally, about 400,000 people are diagnosed with kidney cancer each year. Clear cell renal cell carcinoma is the most common form of kidney cancer among adults, accounting for around 80 per cent of all kidney cancer cases. About one-fifth of those who undergo curative surgery face a relapse within five years. To check for recurrence, the patients need to be scanned– normally using computer tomography – one to two times per year. Scanning entails both radiation exposure and anxiety for many patients.
However, a new international study involving 134 patients from 23 hospitals in ten countries, shows that a simple urine test could halve the number of scans. The urine is analysed to identify certain types of sugar molecules called glycosaminoglycans. The composition of these molecules can serve as biomarkers, known as a GAGome test, in the detection of cancer recurrence.
“The GAGome test is based on a set of biomarkers, rather than just one molecule, which provides a more robust foundation for making decisions about treatment. If the test comes back negative, we are more or less certain that there is no recurrence, but if the test is positive, we must continue to investigate,” says Saeed Dabestani, associate professor at Lund University and senior urology consultant at Kristianstad Central Hospital.
He led the study in which patients who had curative surgery underwent scans, supplemented by regular urine tests, as part of their standard follow-up. The GAGome test was shown to be extremely sensitive regarding the detection of recurrence and could correctly identify 90 per cent of the patients whose cancer had come back. More importantly, emphasises Saeed Dabestani, is that a negative GAGome test resulted in a highly reliable 97 per cent chance that the patient had not had a relapse.
He considers that the test provides significant advantages over simply using scanning:
“A scan often captures small changes that are not large enough for taking a tissue sample and therefore we don’t know if they are signs that the cancer has returned. Our only option is then to carry out more frequent scans, which cause anxiety for the patients and often have little benefit. Using urine tests enables us to better assess the risk, offer more effective checks and potentially halve the number of scans.”
The new test could mean identification of cancer recurrence at an earlier stage, a reduction in radiation exposure and patient anxiety, and lower healthcare costs. However, more research is needed to ascertain if ultimately it will save more lives.
“Further research is needed to confirm the effectiveness of the GAGome test in clinical practice. Our study therefore includes a further group of participants who will be assessed towards the end of 2025 to confirm our current results.”
The GAGome test is being developed by a Swedish diagnostics company and has not yet been approved for clinical use in diagnostic procedures.
