Liquid biopsy technology using circulating tumor DNA (ctDNA) emerged as a transformative biomarker-driven approach to personalized cancer therapy. The IMvigor011 trial demonstrated that ctDNA surveillance can identify muscle-invasive bladder cancer patients at high risk for recurrence after cystectomy, allowing selective treatment with adjuvant atezolizumab [1]. Among ctDNA-positive patients, atezolizumab led to markedly longer disease-free survival (9.9 vs 4.8 months) and overall survival (32.8 vs 21.1 months) compared to placebo, while sparing ctDNA-negative patients from unnecessary immunotherapy toxicity [1]. This biomarker-stratified approach represents a paradigm shift from treating all high-risk patients to treating only those with molecular evidence of residual disease.
Why it matters:
- For clinicians: ctDNA testing provides an actionable tool to personalize adjuvant therapy decisions, avoiding overtreatment in molecular responders while intensifying therapy for those at highest risk. This enables more informed patient counseling about treatment risks and benefits.
- For researchers: The success of ctDNA-guided therapy validates molecular residual disease as a critical endpoint for clinical trials and opens pathways for similar biomarker-driven strategies across other solid tumors.
References
- Powles T, Assaf ZJ, Davarpanah N, et al. ctDNA-Guided Adjuvant Atezolizumab in Muscle-Invasive Bladder Cancer. N Engl J Med. 2025;393(24):2395-2408. doi: 10.1056/NEJMoa2511885 PubMed: https://pubmed.ncbi.nlm.nih.gov/ [PMID not yet assigned in search results]