Can Quantitative Diffusion-Weighted MR Imaging Differentiate Benign and Malignant Cold Thyroid Nodules? Initial Results in 25 Patients

• Published in: American journal of neuroradiology : AJNR 2009-02, Vol.30 (2), p.417-422
• Main Authors: Schueller-Weidekamm, C, Kaserer, K, Schueller, G, Scheuba, C, Ringl, H, Weber, M, Czerny, C, Herneth, A.M
• Format: Article
• Language: English
• Subjects: Adenocarcinoma, Follicular - diagnosis; Adenoma - diagnosis; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Carcinoma, Papillary - diagnosis; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging - methods; Diffusion Magnetic Resonance Imaging - standards; Female; Head & Neck; Human viral diseases; Humans; Infectious diseases; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Neoplasms - diagnosis; Nervous system; Pilot Projects; Prospective Studies; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Reproducibility of Results; Sensitivity and Specificity; Thyroid Neoplasms - diagnosis; Thyroid Nodule - diagnosis; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids
• ISSN: 0195-6108; 1936-959X
• DOI: 10.3174/ajnr.A1338

The characterization of cold nodules of the thyroid gland is mandatory because approximately 20% of these nodules are of malignant origin. The purpose of this study was to evaluate the distinction of cold thyroid nodules by using quantitative diffusion-weighted MR imaging (DWI). In 25 patients with cold nodules on scintigraphy and suggestive findings at fine-needle aspiration, thyroid carcinoma was suggested. In these patients, cold nodules and the normal parenchyma of the contralateral thyroid lobe were prospectively investigated with quantitative DWI (echo-planar imaging sequence; maximum b-value, 800 s/mm(2)) before surgery. The differences in the mean apparent diffusion coefficient (ADC) values in benign and malignant nodules were tested by using a Mann-Whitney U test. Histologically, there were 20 carcinomas with a minimum size of 8 mm and 5 adenomas. The mean ADC values (in 10(-3) mm(2)/s) differed significantly among carcinoma, adenoma, and normal parenchyma (P < .05). The ranges (95% confidence interval) of the ADC values for carcinoma (2.43-3.037), adenoma (1.626-2.233), and normal parenchyma (1.253-1.602) showed no overlap. When an ADC value of 2.25 or higher was used for predicting malignancy, the highest accuracy of 88%, with 85% sensitivity and 100% specificity, was obtained. Quantitative DWI seems to be a feasible tool with which to differentiate thyroid carcinomas from adenomas; however, further studies are required including larger numbers of patients to confirm our results.