Omission of postoperative radioiodine,
does it really help with Noninferior 5-year recurrence-free status in low-risk differentiated thyroid cancer?
research showsGrade B. Five-year recurrence-free rates were 97.9% without ablation and 96.3% with ablation; the absolute difference was 0.5 points (95% CI -2.2 to 3.2), within the prespecified 5-point margin.
ads claimDoing less benefits patients when recurrence is not increased because hospitalization, salivary injury, radiation exposure, and concern about second cancers can be avoided.
Useful facts when choosing a product
- Postoperative radioiodine selection remains a real clinical debate in Korea.
- IoN was funded by Cancer Research UK.
What the research actually shows
① Defect: noninferiority design. ② This matches the listed noninferiority-design item. ③ The paper states, 'Non-inferiority was assessed with a margin of 5 percentage points'; the 0.5-point difference (95% CI -2.2 to 3.2) stayed within it. ④ Noninferiority naturally tests omission, but a stricter margin or superiority-centered design was feasible, so it was counted as avoidable. Central electronic minimization, consistent ITT and PP analyses, and the registered 5-year endpoint were reported, while treatment masking was not feasible.
Why this is classified as B (76)
A 504-person publicly funded hard-outcome trial met its margin, but single-trial noninferiority evidence gives B with 76 points.
Counterpoint. Applicability is strongest for pT1-pT2 and N0/Nx disease without adverse features.
Rejudgment record. Source checked — Large publicly funded hard-outcome RCT meeting a prespecified 5-point margin
| Endpoint | H | Hard endpoint - actual events such as death |
| Replication | R1 | Single confirmatory trial |
| Independence | I2 | Decisive evidence is publicly or non-profit funded |
| Effect size | E+ | Meets the clinically important threshold |
The scoring table and the verdict agree (B).
Sub-claim grades by effect
This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.
| Effect (sub-claim) | Grade | Basis |
|---|---|---|
| Noninferior 5-year recurrence-free status | B | The 5-point margin was met. |
Cross-check — AI research and Codex final gate
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| IoN 2025 | Multicenter randomized noninferiority trial | 504 | Cancer Research UK | 5-year recurrence-free status | 97.9% vs 96.3%; difference 0.5 points (95% CI -2.2 to 3.2), noninferiority P=0.033 | Pivotal evidence |
Receipt — 1 References
All 1 cited sources were verified for existence at the original page (as of 2026-08-26).
Final verification and publication gate: Codex · Verification cutoff: 2026-08-26 · Corrections: none
Cite this verdict
[Chamgap] Benefit of Omitting Postoperative Radioiodine for Noninferior 5-Year Recurrence-Free Status in Low-Risk Differentiated Thyroid Cancer — Evidence Grade B·76. 1 cited sources checked. Source: https://chamgap.com/en/verdicts/general/omit-radioiodine-low-risk-differentiated-thyroid-cancer-recurrence-free/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.