Development and Validation of an MRI-Based Predictive Model for Preoperative Extrathyroidal Extension in Papillary Thyroid Carcinoma

Motivation: Papillary thyroid carcinoma (PTC) recurrence is common, and extrathyroidal extension (ETE) is a critical prognostic factor affecting treatment. Goal(s): This study aimed to develop and validate a predictive model for preoperative ETE in PTC patients using MRI features. Approach: We analyzed 140 confirmed PTC cases. MRI features were evaluated along with clinical data. We identified independent predictors of ETE and developed a predictive nomogram. Predictive performance was assessed. Results: Age, protrude_value, and ADC_Best_rate independently predicted ETE, with the nomogram showing high accuracy and utility across cohorts, MRI systems, and genders, performing better in males. Impact: Our nomogram model, incorporating age, protrude_value, and ADC_Best_rate, effectively predicted preoperative ETE in PTC patients, thereby aiding surgeons in optimizing therapeutic decision-making. ADC_Best_rate demonstrated potential as a robust indicator in MRI functional imaging.