Partial response
Partial response · PR
Tumor shrinkage meeting prespecified partial-response criteria. Under RECIST 1.1, the target-lesion sum of diameters generally must fall by at least 30% from baseline.
How to read it
Check the response criteria, baseline and follow-up measurements, non-target lesions, new lesions and any protocol-required confirmation.
A common pitfall
Shrinkage of one lesion alone does not establish overall PR. Partial response is not cure; diagram values are illustrative.
A simplified example using the same non-nodal target lesions. Overall response also depends on other lesions, new lesions and the study criteria. Numbers are illustrative; response is not cure.
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