Key Clinical Summary:

• Design/Population: The RETAIN-2 trial evaluating response-adapted active surveillance following neoadjuvant dose-dense MVAC plus nivolumab in patients with clinical T2/T3 muscle-invasive bladder cancer, with integrated ctDNA analysis from RETAIN-1 and RETAIN-2.
• Key Outcomes: RETAIN-2 met its primary endpoint, with approximately 60% to 68% of active surveillance patients remaining metastasis-free with an intact bladder at follow-up. Post-neoadjuvant therapy ctDNA clearance strongly predicted metastatic control but did not reliably detect local-only recurrence.
• Clinical Relevance: Response-adapted bladder preservation appears feasible in selected patients with muscle-invasive bladder cancer. ctDNA may guide systemic risk stratification and identify patients who can safely defer immediate cystectomy, though additional strategies are needed to monitor for local recurrence.

Pooja Ghatalia, MD, Fox Chase Cancer Center, Philadelphia, Pennsylvania, discusses results from the phase 2 RETAIN-2 trial and integrated ctDNA analysis from RETAIN-1 and RETAIN-2 evaluating response-adapted bladder preservation in muscle-invasive bladder cancer. 

RETAIN-2 met its primary endpoint of 2-year metastasis-free survival, demonstrating that active surveillance is feasible in selected patients. Integrated ctDNA findings show strong prognostic value for metastatic risk, although ctDNA does not reliably detect local-only bladder recurrence.

Dr Ghatalia presented these results at the 2026 American Society of Clinical Oncology (ASCO) Genitourinary Cancers Symposium in San Francisco, California.

Source: 

Ghatalia P, Ross EA, Zibelman MR, et al. Circulating tumor DNA (ctDNA) to guide response-adapted bladder preservation in muscle invasive bladder cancer (MIBC): Integrated analysis of the RETAIN trials. Presented at ASCO GU. February 26 - 28, 2026. San Francisco, California. LBA632.