# Radioiodine-refractory (RAI-R) thyroid cancer

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

## TL;DR

Thyroid cancer that no longer takes up radioactive iodine, or keeps growing despite it. This is when kinase inhibitor pills come in.

## Summary

Defined by absence of uptake on a diagnostic scan, progression within 12 months of treatment, or cumulative activity >22.2 GBq (600 mCi) without control. Affects ~5-15% of differentiated thyroid cancers, often with BRAF V600E or TERT promoter mutations. Median survival historically 3-5 years; lenvatinib, sorafenib, and genotype-directed drugs (RET, NTRK, BRAF) apply.

## Fields

- Kind: Term
- Last checked: 2026-09-07

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Thyroid_cancer
- ClinicalTrials.gov NCT01321554: SELECT: https://clinicaltrials.gov/study/NCT01321554
- ClinicalTrials.gov NCT00984282: DECISION: https://clinicaltrials.gov/study/NCT00984282

## Connected records

- cancers: [Follicular thyroid cancer](https://onco.cc/cancers/follicular-thyroid-cancer/), [Papillary thyroid cancer](https://onco.cc/cancers/papillary-thyroid-cancer/), [Thyroid cancer](https://onco.cc/cancers/thyroid/)
- technologies: [Radioiodine therapy and whole-body iodine scanning](https://onco.cc/technologies/radioiodine-therapy/)
- trials: [DECISION](https://onco.cc/trials/decision-sorafenib/), [SELECT](https://onco.cc/trials/select-lenvatinib/)
- drugs: [Radioactive iodine (I-131)](https://onco.cc/drugs/radioactive-iodine/)
- pairings: [MAPK inhibitor redifferentiation → radioiodine](https://onco.cc/pairings/redifferentiation-rai/)

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JSON: https://onco.cc/api/v1/entities/rai-refractory.json