The value of breast MRI for BI-RADS category 4B mammographic microcalcification: based on the 5th edition of BI-RADS.

AIM: To investigate whether magnetic resonance imaging (MRI) can improve the positive predictive value (PPV) for Breast Imaging-Reporting and Data System (BI-RADS) category 4B mammographic microcalcification. MATERIALS AND METHODS: One hundred and eight consecutive patients with BI-RADS category 4B microcalcification without mass on mammography underwent breast MRI and subsequent histopathological confirmation between January 2009 and December 2015. Mammography and MRI findings were reviewed retrospectively, and imaging features were analysed according to the 5th edition of BI-RADS. The PPV of each descriptor was analysed to identify subgroups in which PPV could be improved by the addition of MRI. RESULTS: When the criteria of presence of enhancement on MRI was applied to category 4B microcalcification, PPV increased from 0.38 (41 of 108) to 0.82 (37 of 45) and reduced benign biopsy results by 88% (59 of 67). Four ductal carcinoma in situ lesions were missed. For amorphous microcalcification with regional or grouped distribution, MRI images increased PPV without missing malignancy. CONCLUSION: Breast MRI has the potential to improve PPV for category 4B mammographic microcalcification by reducing false-positive findings. If amorphous microcalcification with regional or grouped distribution on mammography shows no enhancement on MRI, follow-up could be considered rather than immediate biopsy. In addition, breast MRI might have the potential to guide the best site to biopsy in category 4B microcalcification.

Pretreatment MRI features associated with diagnostic accuracy of post-treatment MRI after neoadjuvant chemotherapy.

AIM: To investigate whether pretreatment magnetic resonance imaging (MRI) features are associated with diagnostic accuracy of post-treatment MRI for predicting pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) in patients with breast cancer. MATERIALS AND METHODS: From January 2005 and December 2016, 221 consecutive patients (mean age, 50 years; range, 20-81 years) who had undergone NAC, breast MRI before and after NAC, and surgery for invasive breast cancer were enrolled. Pretreatment and post-treatment MRI images were reviewed. Radiological complete response (rCR) was defined as the absence of both early and late enhancement on MRI after NAC. The association of pretreatment MRI features and post-treatment MRI diagnostic accuracy was assessed by using logistic regression analysis. RESULTS: Among 221 patients, 60 (27.1%) underwent pCR after NAC. The diagnostic accuracy of post-treatment MRI was 84.2% (186/221). False-positive diagnosis occurred in 21 cases and false-negative diagnosis occurred in 14 cases. Of pretreatment features, the presence of peritumoural oedema (odds ratio, 3; 95% confidence interval [CI]: 1.1, 8.0; p=0.03) and HER2 (human epidermal growth factor receptor 2)-positive status (odds ratio, 3.4; 95% CI: 1.2, 9.9; p=0.02) were significantly associated with false-positive MRI results. Dense fibroglandular tissue (odds ratio, 10.8; 95% CI: 1.1, 105.2; p=0.04), presence of rim enhancement (odds ratio, 7.5; 95% CI: 1.2, 38.3; p=0.02) and oestrogen receptor (ER)-positive status (odds ratio, 6.3; 95% CI: 1.2, 32.5; p=0.03) were significantly associated with false-negative MRI results. CONCLUSION: Pretreatment MRI features and cancer subtypes may be associated with diagnostic accuracy of post-treatment MRI after NAC in patients with breast cancer.

Interobserver variability and diagnostic performance in US assessment of thyroid nodule according to size.

PURPOSE: To evaluate the interobserver variability for US assessments of thyroid nodules and analyze the diagnostic performances of US assessments in thyroid nodules according to nodule size. MATERIALS AND METHODS: This was an IRB-approved retrospective study with waiver of informed consent. A total of 400 surgically-confirmed thyroid nodules were included. Nodules were divided into 4 groups by size; group 1 (nodule size < 5 mm), group 2 (5 mm ≤ nodule size < 10 mm), group 3 (10 mm ≤ nodule size < 20 mm), and group 4 (nodule size ≥ 20 mm). Three experienced (7 - 10 years) radiologists retrospectively reviewed the US images. Agreement of each US descriptor and final US assessment, and diagnostic performances were calculated in each group and compared. RESULTS: Composition represented substantial or good agreement (k = 0.719 - 0.89). Margin showed the lowest agreement (k = 0.322 - 0.365). Individual kappa values for final assessment according to nodule size were as follows: group 1 (k = 0.674), group 2 (k = 0.596), group 3 (k = 0.674), and group 4 (k = 0.673). Specificity, PPV, and accuracy were significantly different among the groups with different size (p value < 0.05) and lowest in group 1. NPV, specificity, PPV and accuracy except PPV of observer 3 increased with nodule size (p < 0.05). CONCLUSION: Interobserver agreements were relatively good (k = 0.637) in final US assessment regardless of nodule size in experienced radiologists. High false-positive rate was observed in US assessment in nodules less than 5 mm in maximum diameter.

Zooming method (x 2.0) of digital mammography vs digital magnification view (x 1.8) in full-field digital mammography for the diagnosis of microcalcifications.

The purpose of this study was to determine whether the interpretation of microcalcifications assessed on images zoomed (x 2.0) from digital mammograms is at least equivalent to that from digital magnification mammography (x 1.8) with respect to diagnostic accuracy and image quality. Three radiologists with different levels of experience in mammography reviewed each full-field digital mammography reader set for 185 patients with pathologically proven microcalcification clusters, which consisted of digital magnification mammograms (MAGs) with a magnification factor of 1.8 and images zoomed from mammograms (ZOOM) with a zoom factor of 2.0. Each radiologist rated their suspicion of breast cancer in microcalcific lesions using a six-point scale and the image quality and their confidence in the decisions using a five-point scale. Results were analysed according to display methods using areas under the receiver operating characteristic curves (A(z) value) for ZOOM and MAGs to interpret microcalcifications, and the Wilcoxon matched pairs signed rank test for image quality and confidence levels. There was no statistically significant difference in the level of suspicion of breast cancer between the ZOOM and MAG groups (A(z) = 0.8680 for ZOOM; A(z) = 0.8682 for MAG; p = 0.9897). However, MAG images were significantly better than ZOOM images in terms of visual imaging quality (p < 0.001), and the confidence level with MAG was better than with ZOOM (p < 0.001). In conclusion, the performance of radiologists in the diagnosis of microcalcifications using ZOOM was similar to that using MAGs, although image quality and confidence levels were better using MAGs.

Diagnosis of breast cancer at dynamic MRI in patients with breast augmentation by paraffin or silicone injection.

AIM: To determine the diagnostic performance of dynamic magnetic resonance imaging (MRI) for breast cancer in breasts augmented with liquid paraffin or silicone injection. MATERIALS AND METHODS: Among 62 patients with breast augmentation by liquid paraffin or silicone injection who had undergone dynamic breast MRI at our institution, 27 women, who had pathological diagnosis or at least 1-year MRI follow-up, were included in this retrospective study and their MRI images were reviewed. For enhancing lesions on MRI, the morphological features, enhancement kinetics, and BI-RADS assessment category were analysed. The lesion characteristics at MRI were correlated with the final diagnosis based on the histopathological result or at least 1-year MRI follow-up. RESULTS: Of the 27 patients, 17 enhancing lesions in 13 patients were found on MRI. All six lesions that were confirmed as malignancy showed suspicious morphological findings and type 2 or 3 enhancement kinetics, assigned to BI-RADS category 4 or 5. Of the remaining 11 benign lesions, 10 showed benign-favouring morphological findings, and all showed type 1 enhancement kinetics, assigned to BI-RADS category 2 or 4. CONCLUSION: In patients with breasts injected with foreign material, MRI was used to successfully diagnose malignant breast lesions and could be the diagnostic method of choice. Analysis of the morphological and kinetic features at MRI in conjunction with clinical findings is essential.

Molecular and functional expression of anion exchangers in cultured normal human nasal epithelial cells.

AIMS: Anions have an important role in the regulation of airway surface liquid (ASL) volume, viscosity and pH. However, functional localization and regulation of anion exchangers (AEs) have not been clearly described. The aim of this study was to investigate the regulation of AE mRNA expression level in accordance with mucociliary differentiation and the functional expression of AEs cultured normal human nasal epithelial (NHNE) cells. METHODS: Nasal mucosal specimens from three patients are obtained and serially cultured cells are subjected to morphological examinations, RT-PCR, Western blot analysis and immunocytochemistry. AE activity is assessed by pHi measurements. RESULTS: Expression of ciliated cells on the apical membrane and expression of MUC5AC, a marker of mucous differentiation, increased with time. AE2 and SLC26A4 mRNA expression decreased as mucociliary differentiation progressed, and AE4, SLC26A7 and SLC26A8 mRNA expression increased on the 14th and 28th day after confluence. Accordingly, AE4 protein expression also progressively increased. AE activity in 100 mM K(+) buffer solutions was nearly twofold higher than that in 5 mM K(+) buffer solutions. Moreover, only luminal AE activity increased about fourfold over the control in the presence of 5 microM forskolin. In the presence of 100 microM adenosine-5'-triphosphate (ATP) which evokes intracellular calcium signalling through activation of purinergic receptors, only luminal AE activity was again significantly increased. On the other hand, 500 microM 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS), an inhibitor of most SLC4 and SLC26AE isoforms, nearly abolished AE activity in both luminal and basolateral membranes. We found that AE activity was affected by intracellular cAMP and calcium signalling in the luminal membrane and was DIDS-sensitive in both membranes of cultured NHNE cells. CONCLUSION: Our findings through molecular and functional studies using cultured NHNE cells suggest that AEs may have an important role in the regulation of ASL.

Migrated foreign body granulomas on mammography after injection in the cervicofacial area.

AIM: The purpose of this study was to describe the mammographic findings of localized foreign body granulomas in women who were injected with a foreign body in the cervicofacial area to flatten wrinkles. MATERIALS AND METHODS: The teaching files of our institutions were searched, and nine mammograms of migrated foreign body granulomas located. The mammograms were analysed, including the location, shape, size, distribution and depth of the high-density nodules. All these cases had undergone sonography. RESULTS: The migrated foreign body granulomas appeared bilateral (n = 6) or unilateral (n = 3), as oval or round high-density nodules, in the upper inner and/or upper central locations. The average size of the lesions was less than 5 mm in all cases. All nine sonograms showed multiple, round cystic nodules, less than 5 mm in size, with strong posterior shadowing from far upper central to the upper inner breast. Sonography of the lower neck revealed the anatomy could not be visualized due to the strong posterior shadowing in the skin and subcutaneous fat layer. CONCLUSION: Migrated foreign body granulomas appeared on mammograms as localized, multiple oval or round high-density nodules, less than 0.5 cm in size, in the upper inner and/or upper central breast. Breast sonography, including the sonography of the suspected cervicofacial area, is helpful in verifying migrated foreign body granulomas.