Who should read this?
People who have had bladder cancer surgery, or are planning it, and want to understand whether a blood test can help guide decisions about additional treatment.
Which cancer is this about?
Muscle-invasive bladder cancer after surgery, using ctDNA (circulating tumour DNA) to help guide adjuvant treatment decisions.
Why this matters
After bladder cancer surgery, some people are cured and need no further treatment. Others have microscopic cancer cells that cannot be seen on scans and may later cause recurrence.
ctDNA blood testing aims to detect this molecular residual disease earlier than imaging, allowing treatment to be targeted to those most likely to benefit.
Treatment studied
In the IMvigor011 study, ctDNA testing (using the Signatera platform) was used to identify higher-risk patients (ctDNA-positive). Those patients were then randomised to:
• Atezolizumab (immunotherapy)
versus
• Placebo
Results (ctDNA-positive patients)
Disease-free survival:
Median 9.9 months with atezolizumab vs 4.8 months with placebo
Hazard ratio 0.64 (95% CI 0.47–0.87)
Overall survival:
Median 32.8 months with atezolizumab vs 21.1 months with placebo
Hazard ratio 0.59 (95% CI 0.39–0.90)
Key takeaway
ctDNA blood testing after bladder cancer surgery helps identify who is at higher risk of recurrence.
In patients with positive ctDNA, adjuvant immunotherapy significantly improved disease-free and overall survival compared with placebo.