Welcome back to Rad Onc Smart Review.This is Episode 10, Tumor Assays: Growth Delay & TCD50.In our previous episodes, we delved into the cellular responses to radiation, looking at survival curves and models like the LQ model, often derived from in vitro cell culture experiments. But how do tumors respond within the complex environment of a living organism? Today, we're moving from the petri dish to in vivo models, exploring the key experimental assays used to measure how solid tumors respond to radiation treatment, including methods that assess tumor control, cell survival, and growth perturbations.