# Immune-related response criteria (irRC)

Source: https://onco.cc/terms/irrc/  
OnCo record `irrc` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

The immune-related response criteria were the first rules to recognise that a tumour treated with immunotherapy can grow, or show new spots, before it responds.

## Summary

Using phase 2 data on ipilimumab in advanced melanoma, Wolchok and colleagues (Clinical Cancer Research 2009) described four response patterns: shrinkage without new lesions; durable stable disease, sometimes followed by slow decline; response after an initial increase in tumour burden; and response in the presence of new lesions. All were associated with favourable survival. The immune-related response criteria were defined to capture the last two, which RECIST and WHO criteria would have called progression. iRECIST later took over this role in most trials.

## Fields

- Kind: Term
- Last checked: 2026-11-04
- Also known as: irRC; immune-related response criteria

## Sources

- Wolchok et al., Guidelines for the evaluation of immune therapy activity in solid tumors: immune-related response criteria (Clin Cancer Res 2009): https://doi.org/10.1158/1078-0432.ccr-09-1624

## Connected records

- terms: [imRECIST (immune-modified RECIST)](https://onco.cc/terms/imrecist/), [iRECIST (response criteria for immunotherapy trials)](https://onco.cc/terms/irecist/), [RECIST](https://onco.cc/terms/recist/)
- cancers: [Melanoma](https://onco.cc/cancers/melanoma/)
- technologies: [Immune checkpoint inhibitors](https://onco.cc/technologies/checkpoint-inhibitor/)

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JSON: https://onco.cc/api/v1/entities/irrc.json