Detecting ctDNA to predict outcomes in high-grade T1 bladder cancer

T1G3R-1 Trial: Detectability and Prognostic Value of ctDNA in T1 G3 Bladder Cancer, an Exploratory Non-intervention Study.

Observational University Hospital, Basel, Switzerland · NCT07581496

This project will test whether tiny fragments of tumor DNA in urine or blood can be detected and used to predict outcomes for adults with high-grade T1 (T1G3) bladder cancer.

Quick facts

Study typeObservational
Enrollment35 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity Hospital, Basel, Switzerland Academic / other
Locations2 sites (Basel and 1 other locations)
Trial IDNCT07581496 on ClinicalTrials.gov

What this trial studies

This is an observational, non-interventional project enrolling adults with cystoscopically suspected T1G3 bladder cancer who will undergo TUR-B. Investigators will collect urine and plasma samples around standard care procedures to build a biobank for current and future ctDNA testing. The main goals are to determine how often ctDNA can be detected in these patients and whether ctDNA presence or levels relate to disease persistence or progression. No experimental treatments are given and clinical management follows routine care; patients with metastatic disease, concomitant upper-tract tumors, or confirmed non-T1G3 cancers are excluded from further sampling.

Who should consider this trial

Good fit: Adults over 18 with cystoscopically proven bladder cancer suspected to be high-grade T1 (T1G3), able to give informed consent and scheduled for TUR-B at the participating Swiss centers are ideal candidates.

Not a fit: Patients with metastatic disease, concomitant upper-tract tumors, confirmed non-T1G3 pathology, or those who are upstaged at re-TUR-B or immediate cystectomy are unlikely to benefit from this project's ctDNA sampling.

Why it matters

Potential benefit: If successful, ctDNA testing could help identify patients at higher risk who may need earlier or stronger treatment and spare low-risk patients from unnecessary procedures.

How similar studies have performed: Prior research in bladder and other cancers has shown ctDNA can be a promising biomarker for monitoring and prognosis, but its specific use in T1G3 bladder cancer is relatively novel and exploratory.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

All patients \> 18 years of age, able to give informed consent as documented by signature, with a cystoscopically proven bladder cancer, suspicious for T1 stage, estimated by the treating physician, who will undergo TUR-B

Exclusion Criteria:

Patients with metastases or concomitant upper tract tumor at diagnosis will be excluded, Patients with non T1 G3 cancers will be excluded from the study and no further sampling and analyses will take place. Patients with upstaging, either at re-TUR-B or after immediate radical cystectomy will be excluded for further ct-DNA sampling, Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. Vulnerable persons (e.g. \< 18y of age, unable to consent to the study)

Where this trial is running

Basel and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Bladder Cancer
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.