Combining a visual inspection of the bladder—systematic endoscopic evaluation—with a blood test to check for the presence of circulating tumor DNA (ctDNA) may accurately predict which patients with bladder cancer still have cancer in their bladder after treatment and which do not. These findings, presented by Matthew R. Zilbelman, MD, during the 2026 ASCO Genitourinary Cancers Symposium, could someday help urologists identify which patients can safely avoid undergoing cystectomy (Abstract 837).
“These results were even more striking than I expected,” said Dr. Zibelman, Associate Professor in the Department of Hematology/Oncology and Director of Genitourinary Clinical Research at Fox Chase Cancer Center. “It suggests that using these approaches together will be much more powerful than visual inspection alone in predicting absence of disease.”
An Unmet Need for Better Prediction
Current standard of care is to treat patients with bladder cancer with chemotherapy if they can tolerate it, and then proceed to cystectomy.
“But when we actually take it out, some of these patients don’t have any cancer left,” Dr. Zibelman explained. “If we could know better beforehand who still had cancer and who didn’t, we could make more informed decisions about who might be able to safely avoid that big surgery in the first place.”
The new research builds on a previous study by Dr. Zibelman’s team in which surgeons performed cystoscopy to look for signs of cancer remaining in the bladder before surgery. This assessment missed clinically significant cancers around a quarter of the time.
For the new study, researchers tested blood samples taken from the patients on the day of surgery, looking for signs of ctDNA. While other studies have looked at ctDNA in the blood compared to tissue samples from the patients’ tumor, the new study is the largest one to measure ctDNA in blood without requiring that tissue, which would be an easier and faster process for patients and providers.
Key Findings
Combining approaches worked best, researchers found. While the ctDNA test alone correctly identified 68% of patients with residual cancer, using ctDNA and a systematic endoscopic evaluation together increased accuracy to 95%.
The combined approach identified patients who were cancer-free. When both tests were negative, 83% of patients had no cancer remaining, compared to 48% accuracy with the imaging exam alone.
Tests predicted long-term outcomes. Patients with negative ctDNA blood tests lived longer and had less cancer recurrence.
“Our larger goal is ultimately to help patients feel confident about avoiding bladder removal surgery without compromising the long-term risk of recurrence and death from bladder cancer,” Dr. Zibleman said. Researchers are currently conducting a follow-up trial to better understand how the combined approach of cystoscopy and ctDNA tests can be used to guide clinical decisions.
DISCLOSURE: For full disclosures of the study authors, visit coi.asco.org.
