A team introduced a live tumor‑fragment platform that preserves tumor architecture to assess immunotherapy responses ex vivo. The system allows drug exposure and readout of immune‑mediated tumor killing on patient‑derived fragments, offering a potential functional diagnostic to screen therapies prior to patient treatment. The authors describe assay throughput and viability metrics and suggest the platform can complement genomic biomarkers by measuring functional tumor–immune interactions. Developers of predictive diagnostics could use the platform to de‑risk trial enrollment and accelerate combination testing.