Is Doppler ultrasound of additional value to gray-scale ultrasound in differentiating malignant and benign thyroid nodules?

Abstract

SUMMARYThe objective of this study was to evaluate whether Doppler ultrasound (DUS) is of additional value to gray-scale ultrasound (GSUS) in predicting the benign or malignant nature of thyroid nodules. A total of 1,502 solid thyroid nodules ≥ 10 mm were evaluated. Suspicious vascularity (predominantly or exclusively central blood flow) was observed in only 5% of the nodules. This finding showed 96% specificity, but only 15% sensitivity. GSUS alone showed sensitivity and specificity of 88.7% and 68.2%, respectively, which did not improve with the addition of DUS (sensitivity of 89.4% and specificity of 66.4%). In non-suspicious nodules on GSUS, the type of vascularity on DUS did not modify the risk of malignancy, which was low. In suspicious nodules on GSUS, suspicious vascularity on DUS increased the risk of malignancy, but non-suspicious vascularity did not reduce this risk. DUS provided no additional value to GSUS in predicting the benign or malignant nature of thyroid nodules. Arch Endocrinol Metab. 2015;59(1):79-83

Ultrasonography Classification of the American Thyroid Association for Predicting Malignancy in Thyroid Nodules >1cm with Indeterminate Cytology: A Prospective Study

“…The "undefined" category corresponded to iso-or hyperechoic nodules with some suspicious finding, that is, irregular margins, microcalcifications, a taller than wide shape, and rim calcifications with a small extrusive soft tissue component [16]. The type of blood flow of all thyroid nodules was evaluated before FNA: type 0, no vascularity; type 1, peripheral vascularity; type 2, peripheral and intranodular vascularity; type 3, exclusively or predominantly intranodular vascularity, which is considered suspicious of malignancy [12,[17][18][19]. US/Doppler was performed by radiologist experienced in thyroid imaging (A.L.S.)…”

Diagnostic Accuracy of Contrast-Enhanced Ultrasound Enhancement Patterns for Thyroid Nodules

“…Therefore, biopsy was relied on to get the final diagnosis, and is considered the diagnostic criterion standard [8, 9], but biopsy is invasive and has some risk for patients. Previous studies showed that 48–75% of patients who undergo biopsy are subsequently found to have benign lesions [10,11], the overall dissatisfaction rate for FNA is between 10–20% [12], and 2% of samples obtained by CNB are inadequate for histological diagnosis [8]. How to reduce the number of unnecessary biopsies is an area of current research.…”

Is Doppler ultrasonography of value for the differentiation between noninvasive follicular thyroid neoplasm with papillary‐like nuclear features (NIFTP) and invasive encapsulated follicular variant of papillary thyroid carcinoma?

“…Although a higher frequency of nodules with exclusively or predominantly intranodular vascularity (type 3) on Doppler US was observed in iEFVPTC, the difference was not significant. This vascularity, which is suspicious of malignancy, 4,7 was found in a minority of nodules that were NIFTP, but was also uncommon in iEFVPTC. Thus, NIFTP is very similar to iEFVPTC in terms of Doppler US appearance.In conclusion, Doppler US does not contribute to the distinction between NIFTP and iEFVPTC.…”

“…2 The type of blood flow of all thyroid nodules was evaluated before FNA: type 0, no vascularity; type 1, peripheral vascularity; type 2, peripheral and intranodular vascularity; type 3, exclusively or predominantly intranodular vascularity, which is considered suspicious of malignancy. 4,7 Fisher's exact test or the chi-squared test was used to detect differences in the proportion of cases. A P-value of <.05 was considered to be significant.…”