Mount Sinai Study Offers Hope for Bladder Cancer Patients to Avoid Surgery

New York, NY (February 19, 2026) — Researchers at the Icahn School of Medicine at Mount Sinai have reported promising findings that may redefine treatment for patients with muscle-invasive bladder cancer. A study published in the Proceedings of the National Academy of Sciences demonstrates that highly sensitive testing of tumor-derived DNA in blood and urine can help identify patients who may safely preserve their bladder without compromising cancer outcomes.

The Challenge of Muscle-Invasive Bladder Cancer Treatment

Muscle-invasive bladder cancer, an aggressive form of the disease, is traditionally treated with chemotherapy followed by radical cystectomy – the complete removal of the bladder. This is a life-altering procedure with significant impacts on quality of life. However, clinical observations have long suggested that a substantial number of patients have no detectable cancer remaining at the time of surgery, prompting questions about the necessity of such aggressive treatment for all.

A New Approach to Bladder Preservation

“Our goal is to move beyond a one-size-fits-all approach,” said Matthew D. Galsky, MD, Professor of Medicine (Hematology and Medical Oncology) at the Icahn School of Medicine, Deputy Director of the Mount Sinai Tisch Cancer Center and first author of the study. “We are working toward a future where treatment decisions are guided by precise molecular tools that tell us which patients truly need surgery, and which patients may be cured without losing their bladder.”

Detecting Residual Cancer with ctDNA and utDNA

Cancer cells release fragments of DNA into bodily fluids. Researchers can detect these fragments – known as circulating tumor DNA (ctDNA) in blood and urine tumor DNA (utDNA) in urine – using highly sensitive assays to identify traces of residual cancer that may be invisible on traditional scans or biopsies.

Study Findings: Durable Results and Predictive Power

The study analyzed plasma ctDNA and urine utDNA from patients in a clinical trial evaluating a bladder-sparing treatment strategy. Patients who achieved a complete clinical response (no detectable cancer based on tests including bladder biopsies) after systemic therapy were allowed to forgo immediate bladder removal. The results revealed:

• Three-year bladder-intact survival reached 69 percent in patients who achieved a complete clinical response, highlighting the potential for durable bladder preservation in carefully selected individuals.
• Molecular testing can predict metastatic risk. Patients with detectable ctDNA before systemic therapy had a significantly higher likelihood of developing metastatic disease.
• Only 4.5 percent of patients with undetectable baseline ctDNA developed metastases, suggesting ctDNA is a powerful prognostic indicator.
• Patients with undetectable ctDNA before or after treatment demonstrated a low risk of metastatic recurrence.

Complementary Insights from Blood and Urine Testing

The study also showed that plasma and urine DNA testing provide complementary insights. Urine tumor DNA proved more sensitive than blood-based ctDNA for detecting residual disease confined to the bladder. Detectable urine tumor DNA in patients who otherwise showed no evidence of cancer was associated with shorter bladder-intact survival, suggesting urine-based testing can uncover hidden cancer.

“These findings display that blood and urine DNA testing provide complementary information,” Dr. Galsky explained. “Together, they offer a powerful new way to identify patients most likely to benefit from bladder preservation.”

Personalized Care and the Future of Bladder Cancer Treatment

Radical cystectomy, while often curative, requires urinary diversion and can significantly affect daily functioning and quality of life. More precise tools to assess residual disease could spare some patients from unnecessary surgery while maintaining excellent cancer control.

“This research represents an important step toward personalized care in muscle-invasive bladder cancer,” said Dr. Galsky. “As therapies and diagnostics improve, we must ensure we are not overtreating patients who may already be cured.”

The researchers emphasize that these results establish a scientific foundation for incorporating ctDNA and utDNA monitoring into clinical decision-making. Ongoing studies are underway to validate the approach in additional patient cohorts.

Study Collaboration

This study was led by researchers at the Icahn School of Medicine at Mount Sinai and the Mount Sinai Tisch Cancer Center, in collaboration with Johns Hopkins University’s Ludwig Center for Cancer Genetics and Therapeutics. Researchers from institutions including the University of Michigan, City of Hope Comprehensive Cancer Center, Oregon Health & Science University, the University of Utah, the Keck School of Medicine of USC/Norris Comprehensive Cancer Center, the University of Pennsylvania Abramson Cancer Center, and the University of Wisconsin Carbone Cancer Center also contributed.

Full study: https://www.pnas.org/doi/10.1073/pnas.2533449123

About the Icahn School of Medicine at Mount Sinai

The Icahn School of Medicine at Mount Sinai is internationally renowned for its research, education, and clinical care programs. It is the academic partner for the seven member hospitals of the Mount Sinai Health System, providing care to New York City’s diverse patient population. The school offers MD, PhD, MD-PhD, and master’s degree programs, with over 1,200 students enrolled. It also has the largest graduate medical education program in the country, with more than 2,700 clinical residents and fellows.

Ranked 11th nationwide in National Institutes of Health (NIH) funding, the Icahn School of Medicine at Mount Sinai is among the 99th percentile in research dollars per investigator. More than 4,500 scientists, educators, and clinicians work within its academic departments and multidisciplinary institutes, with an emphasis on translational research and therapeutics. Mount Sinai Innovation Partners facilitates the real-world application and commercialization of medical breakthroughs made at Mount Sinai.