Early Evaluation of Relative Changes in Tumor Stiffness by Shear Wave Elastography Predicts the Response to Neoadjuvant Chemotherapy in Patients With Breast Cancer
Neoadjuvant chemotherapy plays an important role in comprehensive therapy for breast cancer, but response prediction is imperfect. Shear wave elastography (SWE) is a novel technique that can quantitatively evaluate tissue stiffness. In this study, we sought to investigate the application value of SWE for early prediction of the response to neoadjuvant chemotherapy in patients with breast cancer.
We prospectively evaluated tumor stiffness in 62 patients with breast cancer using SWE, which was performed at baseline and after the second cycle of neoadjuvant chemotherapy. After chemotherapy, all of the patients underwent surgery. We investigated the correlations between the relative changes in tumor stiffness (Δ stiffness) after 2 cycles of chemotherapy and the pathologic response to the therapy.
Compared with baseline values, tumor stiffness after 2 cycles of neoadjuvant chemotherapy was significantly decreased in responders ( < .001) but not in nonresponders ( = .172). The Δstiffness was significantly higher in responders (−42.194%) than in nonresponders (−23.593%; = .001). As determined at either the baseline or after the second cycle of chemotherapy, tumor stiffness was significantly lower in responders than in nonresponders ( = .033 and .009, respectively). The Δ stiffness threshold for distinguishing between responders and nonresponders was −36.1% (72.92% sensitivity and 85.71% specificity). Furthermore, correlating Δ stiffness with clinical and pathologic characteristics, we found that estrogen and progesterone receptor expression showed statistically significant correlations with Δ stiffness (estrogen receptor, = .008; progesterone receptor, = .023).
Early evaluation of relative changes in tumor stiffness using SWE could effectively predict the response to neoadjuvant chemotherapy in patients with breast cancer and might indicate better therapeutic strategies on a timelier basis.
o August 25, 2015.
o September 22, 2015.
o December 1, 2015.
Sonographic-Pathologic Correlation for Punctate Echogenic Reflectors in Papillary Thyroid Carcinoma
What Are They?
It is commonly held that punctate nonshadowing echogenic foci on sonography, often termed microcalcifications, represent psammoma bodies. We aimed to determine the validity of this supposition by correlating the presence of punctate echogenic foci on sonography with their presence at histopathologic examination.
We examined 51 nodules (surgically proven papillary thyroid carcinoma) by sonography and histopathologic examination. On the latter, nodules were examined for evidence of psammomatous calcifications, dystrophic calcifications, and colloid. Two subspecialty-trained radiologists with 2 and 25 years of experience in sonography, respectively, reviewed the sonograms for the presence and distribution of punctate echogenic foci.
All nodules contained colloid at histologic examination. Twenty of the papillary carcinomas lacked any calcification at pathologic examination. In the remaining 31 nodules with calcifications, 13 had psammomatous calcifications only; 6 had both coarse and psammomatous calcifications; and 12 had only coarse calcifications. The presence of punctate echogenic foci on sonography was 74% sensitive, was 46% to 53% specific, and had a positive predictive value of only 45% to 48% for the presence of psammomatous calcifications. The computed 2-tailed value indicated that the punctate echogenic foci-to-psammoma body correlation was not statistically significant.
The sonographic signature commonly referred to as “microcalcifications” may represent a variety of entities, including psammomatous calcifications, dystrophic calcifications, and eosinophilic colloid; for this reason, “punctate echogenic foci” would be a more accurate term.
o September 15, 2015.
o September 30, 2015.
o October 30, 2015.
Sonographic Characteristics and Interval Changes of Subacute Thyroiditis
This study aimed to assess the sonographic characteristics and interval changes of subacute thyroiditis using follow-up sonography.
From January 2008 to December 2014, 85 patients with clinically suspected subacute thyroiditis underwent sonographic examinations by a single radiologist. Subacute thyroiditis was confirmed on the basis of the clinical, sonographic, and cytohistopathologic findings. On the initial and follow-up sonograms, the individual sonographic findings and interval changes were retrospectively investigated by the same radiologist. According to the sonographic configuration, subacute thyroiditis lesions were categorized as nodular or non-nodular. The interval changes in the lesions were classified as follows: “disappeared,” “decreased,” “increased,” “eventually smaller,” “eventually larger,” or “no interval change.”
Subacute thyroiditis was confirmed in 64 of the 85 patients. In these 64 patients, nodular (n = 39) and non-nodular (n = 35) lesions were found; 10 patients had both nodular and non-nodular lesions. Of the 64 patients, 41 underwent sonographic follow-up. In both nodular and non-nodular lesions, the common interval changes included disappeared, decreased, and eventually smaller patterns. Although the increased pattern was found only in 4 nodular lesions, there was no significant difference in the interval changes between nodular and non-nodular lesions. On follow-up sonography, a new lesion was detected in 6 patients.
The prevalence rate of nodular subacute thyroiditis lesions on sonography was high, and the interval changes in the lesions were variable.
o September 15, 2015.
o October 26, 2015.
o November 25, 2015.
Impact of Image Orientation on Measurements of Thyroid Nodule Stiffness Using Shear Wave Elastography
To assess the effect of orientation on the stiffness measurement by shear wave elastography (SWE) within a thyroid nodule.
Forty-five patients with 50 thyroid nodules were enrolled in this study. After a short sonographic examination, SWE images were acquired in transverse and longitudinal orientations. Multiple elastograms of each nodule were obtained in both orientations. Mean and maximum stiffness values were recorded from each region of interest. The overall mean and maximum stiffness values of each nodule were calculated for both orientations separately. The concordance correlation coefficient was used to assess overall agreement between measurements. A receiver operating characteristic curve analysis was conducted to assess diagnostic performance for benign versus malignant nodules.
The 45 patients included 6 men and 39 women (mean age, 53 years; range, 23–84 years). The mean stiffness values ± SD were 19.1 ± 18.4 and 20.9 ± 21.5 kPa for transverse and longitudinal measurements, respectively, with a small overall bias between the orientations (1.8 kPa; = .09). Overall agreement was good (concordance correlation coefficient, 0.93) although moderated somewhat after the stiffness values were log transformed to reduce skewness (concordance correlation coefficient, 0.76). Of the 50 nodules, 6 were classified as malignant. The area under the curve based on the mean stiffness value from longitudinal images tended to be better than for transverse images, but the difference was not statistically significant (0.93 versus 0.83; = .17).
Our study has shown that good diagnostic performance can be achieved by using SWE in longitudinal and transverse orientations. Moderate to good agreement in mean and maximum stiffness values for both orientations was observed, with only a small bias. Diagnostic performance for benign and malignant nodules was similar. The similar performance of both orientations gives flexibility in imaging patients with October 13, 2015.
o November 9, 2015.
o November 25, 2015.
Copyright © 2016 by the American Institute of Ultrasound in Medicine