Abstract
Objectives
To develop a radiomics score using ultrasound images to predict thyroid malignancy and to investigate its potential as a complementary tool to improve the performance of risk stratification systems.
Methods
We retrospectively included consecutive patients who underwent fine-needle aspiration (FNA) for thyroid nodules that were cytopathologically diagnosed as benign or malignant. Nodules were randomly assigned to a training and test set (8:2 ratio). A radiomics score was developed from the training set, and cutoff values based on the maximum Youden index (Rad_maxY) and for 5%, 10%, and 20% predicted malignancy risk (Rad_5%, Rad_10%, Rad_20%, respectively) were applied to the test set. The performances of the American College of Radiology (ACR) and the American Thyroid Association (ATA) guidelines were compared with the combined performances of the guidelines and radiomics score with interpretations from expert and nonexpert readers.
Results
A total of 1624 thyroid nodules from 1609 patients (mean age, 50.1 years [range, 18–90 years]) were included. The radiomics score yielded an AUC of 0.85 (95% CI: 0.83, 0.87) in the training set and 0.75 (95% CI: 0.69, 0.81) in the test set (Rad_maxY). When the radiomics score was combined with the ACR or ATA guidelines (Rad_5%), all readers showed increased specificity, accuracy, and PPV and decreased unnecessary FNA rates (all p < .05), with no difference in sensitivity (p > .05).
Conclusion
Radiomics help predict thyroid malignancy and improve specificity, accuracy, PPV, and unnecessary FNA rate while maintaining the sensitivity of the ACR and ATA guidelines for both expert and nonexpert readers.
Key Points
• The radiomics score yielded an AUC of 0.85 and 0.75 in the training and test set, respectively.
• For all readers, combining a 5% predicted malignancy risk cutoff for the radiomics score with the ACR and ATA guidelines significantly increased specificity, accuracy, and PPV and decreased unnecessary FNA rates, with no decrease in sensitivity.
• Radiomics can help predict malignancy in thyroid nodules in combination with risk stratification systems, by improving specificity, accuracy, and PPV and unnecessary FNA rates while maintaining sensitivity for both expert and nonexpert readers.
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Abbreviations
- ACR:
-
American College of Radiology
- ATA:
-
American Thyroid Association
- AUC:
-
Area under the receiver operating characteristic curve
- FNA:
-
Fine-needle aspiration
- NPV:
-
Negative predictive value
- PPV:
-
Positive predictive value
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Acknowledgments
This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2019R1A2C1002375). The funders had no role in study design, data collection, and analysis; decision to publish; or preparation of the manuscript.
Funding
This study was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2019R1A2C1002375). The funders had no role in study design, data collection, and analysis; decision to publish; or preparation of the manuscript.
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The scientific guarantor of this publication is Jin Young Kwak, M.D., PhD.
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The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article.
Statistics and biometry
One of the authors (Hye Sun Lee, PhD ) has significant statistical expertise.
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Written informed consent was waived by the Institutional Review Board.
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Institutional Review Board approval was obtained.
Study subjects or cohorts overlap
Among our study population, 507 thyroid nodules in 507 patients were included in a previous study which developed and evaluated the performance of a deep learning–based US computer-aided diagnosis system (Reference: Park VY, Han K, Seong YK et al (2019) Diagnosis of Thyroid Nodules: Performance of a deep learning convolutional neural network model vs. radiologists. Sci Rep 9:17843.).
Methodology
• retrospective
• diagnostic or prognostic study
• performed at one institution
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Park, V.Y., Lee, E., Lee, H.S. et al. Combining radiomics with ultrasound-based risk stratification systems for thyroid nodules: an approach for improving performance. Eur Radiol 31, 2405–2413 (2021). https://doi.org/10.1007/s00330-020-07365-9
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DOI: https://doi.org/10.1007/s00330-020-07365-9