Response evaluation of neoadjuvant therapy in
MIBC
: clinical trial‐derived evidence to guide practice
Roberto Contieri, Bas W.G. van Rhijn, Richard Cathomas, Anja Lorch, Daniela Oprea‐Lager, Paramananthan Mariappan, Francesco Sanguedolce, Antoine G. van der Heijden, Laura S. Mertens, Objectives
To review how response to neoadjuvant therapy (NAT) is assessed in clinical trials of muscle‐invasive bladder cancer (MIBC), and to determine whether trial‐derived evidence can inform response evaluation in contemporary practice.
Subjects/Patients and Methods
We searched PubMed, Embase and ClinicalTrials.gov through August 2025 for randomised controlled trials (RCTs) of neoadjuvant chemotherapy, chemo‐immunotherapy or immunotherapy in non‐metastatic MIBC (cT2–T4a N0–1 M0), and for prospective single‐arm chemo‐immunotherapy or immunotherapy trials. We extracted data on imaging modality and coverage, endoscopic and biomarker‐based assessment, timing, correlation with final pathology and diagnostic accuracy. Given heterogeneity in definitions and reporting, no meta‐analysis was performed.
Results
We identified 22 studies, including 14 RCTs. Most incorporated response evaluation, yet methods differed widely. Computed tomography (CT) was the most frequent modality in RCTs, whereas bladder magnetic resonance imaging (MRI) predominated in recent single‐arm immunotherapy trials. Timing was inconsistent and usually post‐treatment; only two trials performed interim assessment. Endoscopic evaluation was concentrated in bladder‐preservation trials, and circulating tumour DNA (ctDNA) was used selectively. Only five studies correlated restaging with final pathology; multiparametric MRI scored with nacVI‐RADS predicted pathological complete response with 72%–83% accuracy. No trial reported imaging accuracy for distant metastases after NAT.
Conclusion
Response assessment after NAT in MIBC remains insufficiently standardised. Trial‐derived evidence supports cross‐sectional imaging before radical local treatment, with CT the most established modality, largely reflecting trial‐design conventions and availability rather than demonstrated diagnostic superiority; bladder MRI is more accurate for local restaging. Emerging biomarkers such as ctDNA require validation. Harmonising timing, modalities and response definitions is needed to enable evidence‐based treatment adaptation.