Diagnostic value of dynamic contrast medium enhanced magnetic resonance imaging in preoperative detection of thyroid carcinoma.

Objective: To assess the diagnostic value of dynamic contrast medium-enhanced magnetic resonance imaging (DCE-MRI) in detection of thyroid carcinoma compared with fine-needle aspiration biopsy and frozen section analysis in multinodular goiter.

Design: Prospective clinical study.

Setting: University hospital.

Patients: Thirty consecutive patients with nodular goiter without any clinical risk and symptoms associated with thyroid carcinoma were studied. Twenty-five patients had euthyroid multinodular goiter, and 5 had toxic nodular goiter. Scintigraphy, ultrasonography, and DCE-MRI were performed preoperatively in all patients, as well as fine-needle aspiration biopsy and frozen section analysis in 17 patients with dominant cold nodules.

Main Outcome Measures: Contrast enhancement patterns on DCE-MRIs and histopathologic results of thyroidectomy specimens were correlated. The sensitivity, specificity, diagnostic accuracy, and positive and negative predictive values of DCE-MRI and the results of fine-needle aspiration biopsy and preoperative frozen section analysis to detect thyroid carcinoma were compared.

Results: Thyroid carcinoma was found in 11 patients (36.7%), but was clinically significant in only 4 (13.3%). Delayed washout pattern of contrast enhancement significantly correlated with a histologic diagnosis of thyroid carcinoma (P < .001). The conditional probability of thyroid cancer in a patient with multinodular goiter with a delayed washout pattern was 0.78. The sensitivity and diagnostic accuracy of DCE-MRI to detect thyroid carcinoma was higher compared with fine-needle aspiration biopsy and frozen section analysis (100% vs 50% and 85.7%, and 90% vs 70.6% and 87.5%, respectively). The negative predictive value of DCE- MRI was 100%, ruling out thyroid carcinoma in all patients with benign goiter.

Conclusion: Dynamic contrast-enhanced magnetic resonance imaging is useful to detect or exclude thyroid carcinoma with high diagnostic accuracy in patients with multinodular goiter when results of other diagnostic methods are inconclusive.