HiLo
Showed a third of the usual radioactive iodine dose ablates the thyroid remnant just as well, with fewer side effects and less time in isolation.
Ablation success 85% in both dose groups (NEJM 2012); recombinant TSH avoided hypothyroid symptoms. Low-dose ablation became standard for intermediate-risk disease, and the trial paved the way to omitting ablation altogether in low-risk disease.
Setting
Differentiated thyroid cancer needing ablation: low-dose (1.1 GBq) vs high-dose (3.7 GBq) radioiodine, with recombinant TSH or thyroid hormone withdrawal
Phase
Phase 3
Sponsor
Cancer Research UK
Registry
Headline result
Ablation success 85.0% (1.1 GBq) vs 88.9% (3.7 GBq), non-inferior.
Reported
2012
Enrolled
438
Replication
ESTIMABL1 (France) replicated low-dose non-inferiority simultaneously.
In plain words
What these results mean for people, not percentages
Successful ablationprimaryother endpoint
- 85 vs 88.9 out of 100 reached this endpoint with 1.1 GBq compared with 3.7 GBq; 3.9 fewer per 100.
- On this measure the first group did worse, not better.
- This endpoint is not one of the standard survival or response measures; read it alongside the trial's primary result.
- These results apply to the people the trial enrolled: Differentiated thyroid cancer needing ablation: low-dose (1.1 GBq) vs high-dose (3.7 GBq) radioiodine, with recombinant TSH or thyroid hormone withdrawal. People in a different situation may not see the same effect.
Numbers are from the trial as recorded here; see the source links in the table below. This is orientation, not medical advice: ask your team how closely the trial population matches you.