Immunotherapy Response Assessment in Solid Tumors
Pronunciation: eye-REH-sist
Also written as: iRECIST — Immunotherapy Response Assessment in Solid Tumors
Modified response criteria specifically designed to evaluate tumor response to immunotherapy agents.
Full Definition
iRECIST represents an adaptation of traditional RECIST criteria specifically developed for assessing tumor response to immunotherapy. These criteria account for the unique response patterns seen with immune checkpoint inhibitors, including initial apparent progression followed by response (pseudoprogression) and the development of new lesions that may represent immune infiltration rather than true disease progression. The criteria require confirmation of progression on subsequent imaging to distinguish true progression from immune-mediated effects.
Usage
Usage note: Use lowercase 'i' followed by uppercase 'RECIST' when abbreviated.
In Context
- "The oncologist requested iRECIST assessment given the patient's treatment with pembrolizumab." — Clinical consultation
- "Using iRECIST criteria, the apparent progression required confirmation imaging before treatment modification." — Multidisciplinary conference