Long‐term predictive value of highly sensitive thyroglobulin measurement
Authors' conclusion
Except for patients with distant metastases, both TgAb negative and TgAb positive patients with an undetectable nonstimulated hsTg measurement have a very good prognosis. The high net present value of unstimulated hsTg testing means that further diagnostic procedures can be omitted in such patients.
Study context
- Population
- Differentiated thyroid cancer (DTC) patients referred for treatment and follow-up from 2004 onwards, with ≥1 posttreatment thyroglobulin (Tg) measured ≥3 months after I-131 ablation
- Participants
- 461 patients
- Exposure
- Unstimulated highly sensitive thyroglobulin (hsTg) ≥0.1 ng/ml vs stimulated Tg ≥1.0 ng/ml as reference
- TgAb-negativen = 410
- TgAb-positiven = 51
- Outcome
- Predictive value of unremarkable nonstimulated hsTg for stimulated Tg, diagnostic whole-body scintigraphy, recurrence and DTC-related death
Methodological detailsdiagnostic accuracy
- Diagnostic accuracy
Main finding
As reported in the abstract
Unstimulated hsTg ≥0.1 ng/ml for stimulated Tg ≥1.0 ng/ml
| Group | Sensitivity | Specificity | PPV | NPV |
|---|---|---|---|---|
| TgAb-negative | 90.0% | 94.1% | 77.6% | 97.6% |
| TgAb-positive | 75% | 97% | 75% | 97% |
Sensitivity
TgAb-negative90.0%
TgAb-positive75%
Specificity
TgAb-negative94.1%
TgAb-positive97%
PPV
TgAb-negative77.6%
TgAb-positive75%
NPV
TgAb-negative97.6%
TgAb-positive97%
Observational data: associations, not effects.
Further findings
Stimulated Tg ≥1.0 ng/ml by unstimulated Tg category, TgAb-negative
- Unstimulated Tg <0.1 ng/ml
- 2.0%
- Unstimulated Tg ≥0.1 but <1.0 ng/ml
- 77.6%
Discrimination of DTC-related death risk
- Unstimulated Tg ≥0.1 ng/ml: not significant
- P = 0.06
- Unstimulated Tg ≥1.0 ng/ml: significant
- P = 0.012
- Stimulated Tg ≥1.0 ng/ml: significant
- P = 0.029
- Excluding patients with distant metastases at diagnosis nullifies this significance
Original publication
Long‐term predictive value of highly sensitive thyroglobulin measurement. Clin Endocrinol (Oxf). Published 1 November 2022. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →