Yes. That makes sense.
If a tumor shrinks, and shrinks a lot , then yes, of course I would expect it to correlate better with OS than a tumor that shrinks by a little bit. Unless special circumstances apply, such as primary tumor shrinkage happening at the same time as a metastatic process is happening.
But what is more important than depth of response is duration of response. Which that study does not look at.
And a durable response (measures by tumor shrinkage) that persists over an extended period of time, would be a better predictor than DpR.
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