Urine test could reduce kidney cancer scan frequency

[WORLD] Researchers propose that a simple urine test could accurately detect reoccurring kidney cancer in patients recovering from surgery, perhaps sparing them from frequent follow-up scans. The AUR87A trial, coordinated by Swedish researchers, involved 134 patients treated in 23 institutions across the United Kingdom, Europe, the United States, and Canada.

All were identified as clear cell renal cell carcinoma (ccRCC), the most prevalent type of kidney cancer, which had not progressed beyond the kidney and could be treated surgically. Most individuals had their kidneys removed totally.

Kidney cancer is among the top 10 most common cancers worldwide, with over 400,000 new cases diagnosed annually. Clear cell renal cell carcinoma accounts for roughly 70% of these cases, making early detection of recurrence critical for improving survival rates. Current surveillance methods rely heavily on imaging, which can be costly, time-consuming, and expose patients to repeated radiation.

This kind of cancer returns in approximately one-fifth of persons, usually within one to two years. Patients are monitored by computed tomography (CT) scans, the frequency of which is determined by their particular risk level.

For the study, the participants had CT scans as part of their normal post-operative surveillance, as well as a urine test every three months. These tests examined the profiles of specific sugar molecules found in urine, known as glycosaminoglycans, and assigned patients a GAGome score out of 100.

Glycosaminoglycans are long chains of sugars that play a role in cell signaling and tissue structure. Abnormal levels or patterns of these molecules have previously been linked to various cancers, including prostate and bladder cancer. The GAGome score represents a novel application of this biomarker, offering a non-invasive way to monitor kidney cancer progression.

After 18 months, cancer had reappeared in 15% of the participants. The study discovered that the urine test successfully indicated recurrence in 90% of these patients. It also correctly ruled out returning cancer in slightly more than half of the patients who stayed cancer-free.

While the specificity of the test—its ability to correctly identify patients without recurrence—was around 50%, researchers emphasize that its high sensitivity (90%) makes it a valuable tool for ruling out false negatives. Combining the urine test with selective imaging could significantly reduce unnecessary scans while ensuring timely detection of relapse.

According to Saeed Dabestani, an associate professor at Lund University and consultant urologist at Kristianstad Central Hospital in Sweden, CT scans can detect small tumors that cannot be biopsyed. It is unclear whether these lesions indicate cancer recurrence. Frequent scans are the only option for regularly monitoring patients, although they can be uncomfortable and provide little benefit.If you have a urine test that can properly detect whether the cancer has returned, you can better assess risk and reduce the number of scans required.

“Based on the results we have so far, it’s likely that we could safely halve the number of scans that patients have to undergo.” The study was presented at the European Association of Urology (EAU) Congress in Madrid, Spain, and accepted for publication in the journal European Urology Oncology.

If further validated, this urine test could become part of routine post-operative care for kidney cancer patients, aligning with a growing trend toward liquid biopsies in oncology. Similar tests are already in use for bladder cancer surveillance, highlighting the potential for broader adoption across urological cancers.

Researchers are currently recruiting a second group of patients for the AUR87A study, and results are expected towards the end of the year.