Reducing Overtreatment of Indeterminate Thyroid Nodules Using a Multimodal Deep Learning Model
Shreeram Athreya, Andrew Melehy, Sujit Silas Armstrong Suthahar, Vedrana Ivezić, Ashwath Radhachandran, Vivek Sant, Chace Moleta, Henry Zheng, Maitraya Patel, Rinat Masamed, Corey W. Arnold, William Speier
TL;DR
This study tackles overtreatment of indeterminate thyroid nodules by integrating ultrasound imaging with molecular testing through an attention-based multiple instance learning framework. The multimodal AMIL model fuses US-derived features with MT outcomes to classify nodules as benign or malignant, aiming to preserve MT’s high sensitivity while reducing false positives. Across 333 cases, the ensemble approach achieved the highest AUROC (0.831) and improved PPV (0.477) compared to MT alone (0.448), suggesting fewer unnecessary surgeries. The method provides interpretable attention maps and presents a clinically meaningful step toward more precise, less invasive management of indeterminate nodules, pending prospective validation.
Abstract
Objective: Molecular testing (MT) classifies cytologically indeterminate thyroid nodules as benign or malignant with high sensitivity but low positive predictive value (PPV), only using molecular profiles, ignoring ultrasound (US) imaging and biopsy. We address this limitation by applying attention multiple instance learning (AMIL) to US images. Methods: We retrospectively reviewed 333 patients with indeterminate thyroid nodules at UCLA medical center (259 benign, 74 malignant). A multi-modal deep learning AMIL model was developed, combining US images and MT to classify the nodules as benign or malignant and enhance the malignancy risk stratification of MT. Results: The final AMIL model matched MT sensitivity (0.946) while significantly improving PPV (0.477 vs 0.448 for MT alone), indicating fewer false positives while maintaining high sensitivity. Conclusion: Our approach reduces false positives compared to MT while maintaining the same ability to identify positive cases, potentially reducing unnecessary benign thyroid resections in patients with indeterminate nodules.
