Triple-negative breast cancer: what the radiologist needs to know

DCE-MRI Radiomic analysis in triple negative ductal invasive breast cancer. Comparison between BRCA and not BRCA mutated patients: Preliminary results

OBJECTIVE

The research aimed to determine whether and which radiomic features from breast dynamic contrast enhanced (DCE) MRI could predict the presence of BRCA1 mutation in patients with triple-negative breast cancer (TNBC).

MATERIAL AND METHODS

This retrospective study included consecutive patients histologically diagnosed with TNBC who underwent breast DCE-MRI in 2010-2021. Baseline DCE-MRIs were retrospectively reviewed; percentage maps of wash-in and wash-out were computed and breast lesions were manually segmented, drawing a 5 mm-Region of Interest (ROI) inside the tumor and another 5 mm-ROI inside the contralateral healthy gland. Features for each map and each ROI were extracted with Pyradiomics-3D Slicer and considered first separately (tumor and contralateral gland) and then together. In each analysis the more important features for BRCA1 status classification were selected with Maximum Relevance Minimum Redundancy algorithm and used to fit four classifiers.

RESULTS

The population included 67 patients and 86 lesions (21 in BRCA1-mutated, 65 in non BRCA-carriers). The best classifiers for BRCA mutation were Support Vector Classifier and Logistic Regression in models fitted with both gland and tumor features, reaching an Area Under ROC Curve (AUC) of 0.80 (SD 0.21) and of 0.79 (SD 0.20), respectively. Three features were higher in BRCA1-mutated compared to non BRCA-mutated: Total Energy and Correlation from gray level cooccurrence matrix, both measured in contralateral gland in wash-out maps, and Root Mean Squared, selected from the wash-out map of the tumor.

CONCLUSIONS

This study showed the feasibility of a radiomic study with breast DCE-MRI and the potential of radiomics in predicting BRCA1 mutational status.

A Radiomics Model Based on Synthetic MRI Acquisition for Predicting Neoadjuvant Systemic Treatment Response in Triple-Negative Breast Cancer

Purpose To determine if a radiomics model based on quantitative maps acquired with synthetic MRI (SyMRI) is useful for predicting neoadjuvant systemic therapy (NAST) response in triple-negative breast cancer (TNBC). Materials and Methods In this prospective study, 181 women diagnosed with stage I-III TNBC were scanned with a SyMRI sequence at baseline and at midtreatment (after four cycles of NAST), producing T1, T2, and proton density (PD) maps. Histopathologic analysis at surgery was used to determine pathologic complete response (pCR) or non-pCR status. From three-dimensional tumor contours drawn on the three maps, 310 histogram and textural features were extracted, resulting in 930 features per scan. Radiomic features were compared between pCR and non-pCR groups by using Wilcoxon rank sum test. To build a multivariable predictive model, logistic regression with elastic net regularization and cross-validation was performed for texture feature selection using 119 participants (median age, 52 years [range, 26-77 years]). An independent testing cohort of 62 participants (median age, 48 years [range, 23-74 years]) was used to evaluate and compare the models by area under the receiver operating characteristic curve (AUC). Results Univariable analysis identified 15 T1, 10 T2, and 12 PD radiomic features at midtreatment that predicted pCR with an AUC greater than 0.70 in both the training and testing cohorts. Multivariable radiomics models of maps acquired at midtreatment demonstrated superior performance over those acquired at baseline, achieving AUCs as high as 0.78 and 0.72 in the training and testing cohorts, respectively. Conclusion SyMRI-based radiomic features acquired at midtreatment are potentially useful for identifying early NAST responders in TNBC. Keywords: MR Imaging, Breast, Outcomes Analysis ClinicalTrials.gov registration no. NCT02276443 Supplemental material is available for this article. © RSNA, 2023 See also the commentary by Houser and Rapelyea in this issue.

Identification of triple-negative breast cancer and androgen receptor expression based on histogram and texture analysis of dynamic contrast-enhanced MRI

BACKGROUND

Triple-negative breast cancer (TNBC) is highly malignant and has a poor prognosis due to the lack of effective therapeutic targets. Androgen receptor (AR) has been investigated as a possible therapeutic target. This study quantitatively assessed intratumor heterogeneity by histogram analysis of pharmacokinetic parameters and texture analysis on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to discriminate TNBC from non-triple-negative breast cancer (non-TNBC) and to identify AR expression in TNBC.

METHODS

This retrospective study included 99 patients with histopathologically proven breast cancer (TNBC: 36, non-TNBC: 63) who underwent breast DCE-MRI before surgery. The pharmacokinetic parameters of DCE-MRI (K^trans, K_ep and V_e) and their corresponding texture parameters were calculated. The independent t-test, or Mann-Whitney U-test was used to compare quantitative parameters between TNBC and non-TNBC groups, and AR-positive (AR+) and AR-negative (AR-) TNBC groups. The parameters with significant difference between two groups were further involved in logistic regression analysis to build a prediction model for TNBC. The ROC analysis was conducted on each independent parameter and the TNBC predicting model for evaluating the discrimination performance. The area under the ROC curve (AUC), sensitivity and specificity were derived.

RESULTS

The binary logistic regression analysis revealed that K_{ep_Range} (p = 0.032) and V_{e_SumVariance} (p = 0.005) were significantly higher in TNBC than in non-TNBC. The AUC of the combined model for identifying TNBC was 0.735 (p < 0.001) with a cut-off value of 0.268, and its sensitivity and specificity were 88.89% and 52.38%, respectively. The value of K_{ep_Compactness2} (p = 0.049), K_{ep_SphericalDisproportion} (p = 0.049), and V_{e_GlcmEntropy} (p = 0.008) were higher in AR + TNBC group than in AR-TNBC group.

CONCLUSION

Histogram and texture analysis of breast lesions on DCE-MRI showed potential to identify TNBC, and the specific features can be possible predictors of AR expression, enhancing the ability to individualize the treatment of patients with TNBC.

Intramammary edema of invasive breast cancers on MRI T2-weighted fat suppression sequence: Correlation with molecular subtypes and clinical-pathologic prognostic factors

OBJECTIVE

To investigate the associations between different patterns of intramammary edema on preoperative 3.0 T magnetic resonance imaging (MRI) T₂-weighted fat suppression sequence and invasive breast cancer molecular subtypes and clinical-pathologic prognostic factors.

METHODS

Between May 2014 and December 2020, 191 patients with invasive breast cancer who had undergone preoperative MRI and mastectomy or breast-conserving surgery were retrospectively enrolled. The relationships between different patterns of intramammary edema and invasive breast cancer molecular subtypes and clinical-pathologic features were evaluated using the Student's t-test or Mann-Whitney U test and the χ2 test or Fisher's exact test.

RESULTS

Patients with luminal B (HER2 positive), HER2-enriched and triple negative breast cancers respectively had different patterns of intramammary edema (P < 0.001). There was a significant association between intramammary edema and clinical-pathologic factors, including larger tumor size, higher Ki-67 index, lymph node metastasis and lymphovascular invasion (all P < 0.001).

CONCLUSIONS

Intramammary edema may provide added values of predicting molecular subtypes and clinical-pathologic prognosis, enhancing the ability to individualize the treatment of patients with invasive breast cancer.

Triple-negative breast cancer on contrast-enhanced MRI and synthetic MRI: A comparison with non-triple-negative breast carcinoma

PURPOSE

This study aimed to compare the characteristics of triple-negative breast cancer (TNBC) with non-TNBC on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and synthetic MRI.

METHOD

This retrospective study included 79 patients with histopathologically proven breast cancer (TNBC: 16, non-TNBC: 63) who underwent synthetic MRI. Using synthetic MR images, we obtained T1 and T2 relaxation times in breast lesions before (Pre-T1, Pre-T2, Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD) contrast agent injection. Subsequently, we calculated the ΔT1 (Pre-T1 - Gd-T1), ΔT2 (Pre-T2 - Gd-T2), Pre-T1/T2, and Gd-T1/T2. We compared the aforementioned quantitative values, as well as several morphologic features between TNBCs and non-TNBCs that were identified on DCE-MRI.

RESULTS

The multivariate analyses revealed that the Pre-T2 (P = 0.037) and the presence of rim enhancement (P-RIM) (P = 0.034) were significant and independent predictors of TNBC. The area under the receiver operating characteristics curve for all breast cancers was greater when a combination of Pre-T2 and P-RIM (Pre-T2＋P-RIM; Method 3, AUC (area under the curve) = 0.858) was used to distinguish between TNBCs and non-TNBCs versus the use of either Pre-T2 alone (Method 1, AUC = 0.786) or P-RIM alone (Method 2, AUC = 0.747).

CONCLUSIONS

Pre-T2 obtained using synthetic MRI and P-RIM identified on DCE-MRI allowed the differentiation between TNBCs and non-TNBCs. However, these results are preliminary and need to be verified by further studies.

Added value of histogram analysis of apparent diffusion coefficient maps for differentiating triple-negative breast cancer from other subtypes of breast cancer on standard MRI

Background

Triple-negative breast cancers generally occur in young women with remarkable potential to be aggressive. It will be of great help to detect this subtype of tumor early. To retrospectively evaluate the performance of histogram analysis of apparent diffusion coefficient (ADC) maps in distinguishing triple-negative breast cancer (TNBC) from other subtypes of breast cancer (non-TNBC), when combined with magnetic resonance imaging (MRI) features.

Materials and methods

From February 2014 to December 2018, 192 patients were included in this study taking preoperative standard MRI (s-MRI) and DWI. Seventy-six of them were pathologically confirmed with TNBC and rest 116 with other subtypes. First, their clinical-pathological features and morphological characteristics on MRI were assessed, including tumor size, foci quantity, tumor shape, margin, internal enhancement, and time-signal intensity curve types, in addition to the signal intensity on T2-weighted images. Second, whole-lesion apparent diffusion coefficient (ADC) histogram analysis was executed. Finally, both univariate and multivariate regression analyses were applied to identify the most useful variables in separating TNBCs from non-TNBCs, and then their effects were evaluated following receiver operating characteristic curve analysis.

Result

Multivariate regression analysis indicated that circumscribed margin, rim enhancement, and ADC₉₀ were important predictors for TNBC. Increased area under curve (AUC) and improved specificity can be obtained when combined s-MRI and DWI (circumscribed margin+rim enhancement+ADC₉₀>1.47×10⁻³ mm²/s) is taken as the criterion, other than s-MRI (circumscribed margin+rim enhancement) alone (s-MRI+DWI vs s-MRI; AUC, 0.833 vs 0.797; specificity, 98.3% vs 89.7%; sensitivity, 68.4% vs 69.7%).

Conclusion

Circumscribed margin and rim enhancement on s-MRI and ADC₉₀ are three important elements in detecting TNBC, while ADC histogram analysis can provide additional value in this detection.

CC chemokines are differentially expressed in Breast Cancer and are associated with disparity in overall survival

Despite recent advances, breast cancer (BrCa) still affects many women and the impact is disproportional in African Americans (AA) compared to European Americans (EA). Addressing socioeconomic and behavioral status has not been enough to reduce disparity, suggesting contribution of biological differences in BrCa disparity. Our laboratory was first to show involvement of CC chemokines in BrCa. In this study, using ONCOMINE, TCGA, bc-GenExMiner and KMplotter, we examined the association of CC chemokines in BrCa outcomes and disparity. We show over-expression of CCL5, -7, -11, -17, -20, -22 and -25 in BrCa tissues. High mRNA levels of CCL7, -8, -17, -20 and -25 predicted a decrease in overall survival (OS). CCL7 and CCL8 were associated with decreased relapse-free survival. Expression of CCL17 and CCL25 was associated with decreased OS in AA. In EA, CCL8 was associated with decreased OS. Expression of CCL5, -7, -8, -17, -20 and -25 was highest in TNBC. Expression of CCL11 and CCL22 was associated with HER2. CCL7, -8, -17, -20 and -25 were elevated in AAs. In conclusion, our analysis suggests significant association of CC-chemokines in BrCa progression, OS and disparate disease outcome in AA compared to EA patients.

Differences in Multi-Modal Ultrasound Imaging between Triple Negative and Non-Triple Negative Breast Cancer

The objective of this study was to identify multi-modal ultrasound imaging parameters that could potentially help to differentiate between triple negative breast cancer (TNBC) and non-TNBC. Conventional ultrasonography, ultrasound strain elastography and 3-D ultrasound (3-D-US) findings from 50 TNBC and 179 non-TNBC patients were retrospectively reviewed. Immunohistochemical examination was used as the reference gold standard for cancer subtyping. Different ultrasound modalities were initially analyzed to define TNBC-related features. Subsequently, logistic regression analysis was applied to TNBC-related features to establish models for predicting TNBC. TNBCs often presented as micro-lobulated, markedly hypo-echoic masses with an abrupt interface (p = 0.015, 0.0015 and 0.004, compared with non-TNBCs, respectively) on conventional ultrasound, and showed a diminished retraction pattern phenomenon in the coronal plane (p = 0.035) on 3-D-US. Our findings suggest that B-mode ultrasound and 3-D-US in multi-modality ultrasonography could be a useful non-invasive technique for differentiating TNBCs from non-TNBCs.

Role of MRI in the staging of breast cancer patients: does histological type and molecular subtype matter?

OBJECTIVE

To assess the role of MRI in the pre-operative staging of patients with different histological types and molecular subtypes of breast cancer, by the assessment of the dimensions of the main tumour and identification of multifocal and/or multicentric disease.

METHODS

The study included 160 females diagnosed with breast cancer who underwent breast MRI for pre-operative staging. The size of the primary tumour evaluated by MRI was compared with the pathology (gold standard) using the Pearson's correlation coefficient (r). The presence of multifocal and/or multicentric disease was also evaluated.

RESULTS

The mean age of patients was 52.6 years (range 30-81 years). Correlation between the largest dimension of the main tumour measured by MRI and pathology was worse for non-special type/invasive ductal carcinoma than for other histological types and was better for luminal A and triple-negative than for luminal B and Her-2 molecular subtypes. Multifocal and/or multicentric disease was present in 48 patients (30.0%), and it was more common in breast carcinomas classified as Her-2 molecular subtype. There was no statistically significant difference in the frequency of multifocal and/or multicentric tumours identified only by MRI in relation to histological type or molecular subtype.

CONCLUSION

The results of this retrospective study demonstrated that histological types and molecular subtypes might influence the MRI assessment of breast cancers, especially in the evaluation of tumour size.

ADVANCES IN KNOWLEDGE

The real benefit of MRI for treatment planning in patients with breast cancer may be different according to the histological type and molecular subtype.

Mammographic and sonographic features of triple-negative invasive carcinoma of no special type

The aim of this study was to compare the mammography, ultrasound (US) and histologic features of triple-negative (TN) invasive carcinoma of no special type (NST) to non-TN invasive carcinoma of NST. The second aim was to assess whether the distinct imaging characteristics of TN breast cancer would persist after controlling for the histologic features. A total of 344 invasive carcinomas of NST in 337 patients from January 2007 to February 2008 were included in this study. Two radiologists retrospectively reviewed the mammography and US findings using the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) lexicon and our institution's criteria. On mammography, TN invasive carcinoma of NST most commonly presented as a mass with round shape and non-spiculated margin. On US, it was more likely to have internal hypoechogenicity, an abrupt boundary and posterior acoustic enhancement. TNBC lacked major suspicious imaging findings such as an irregular shape, spiculated margin and calcification.

Invasive ductal carcinoma of the breast in a 14-year-old girl

Breast cancer is rare in children and adolescents. In particular, there are very few cases of invasive ductal carcinoma in childhood. We report a case of invasive ductal carcinoma of the breast in a 14-year-old girl presenting as a palpable mass. While the tumor demonstrated a relatively benign appearance on ultrasound, magnetic resonance imaging revealed typical malignant features. Several polymorphisms of single nucleotide variation were observed on gene analysis. The patient underwent breast conserving surgery and received subsequent concurrent chemo-radiation therapy. An awareness that ductal carcinoma of the breast rarely occurs in children is important to detect early stage breast cancer.

Correlation between imaging and prognostic factors: molecular classification of breast cancers

The new molecular classification of breast cancers defines cancer sub-groups with a distinct prognosis and response to treatment. Studies on the literature deal with the imaging of each tumour sub-type. The radiologist should be familiar with them in order to adapt the care of an aggressive sub-type. In view of the current knowledge, the following have been significantly more often observed: mammographical spiculated mass with echogenic halo in luminal A sub-type; architectural distortion in luminal B sub-type; an irregular mass with indistinct margin comprising microcalcifications, with an abrupt interface in the sonography, or non-sonographic mass in the HER2 sub-type; a very hypoechogenic, lobulated mass with indistinct or microlobulated margin, with an abrupt interface, sometimes pseudo-benign, in the triple-negative sub-type.

MR imaging features of triple-negative breast cancers

Triple-negative (TN) breast cancers, which are associated with a more aggressive clinical course and poorer prognosis, often present with benign imaging features on mammography and ultrasound. The purpose of this study was to compare the magnetic resonance imaging features of TN breast cancers with estrogen (ER) and progesterone (PR) positive, human epidermal growth factor receptor (HER2) negative cancers. Retrospective review identified 140 patients with TN breast cancer who underwent a preoperative breast MRI between 2003 and 2008. Comparison was made to 181 patients with ER+/PR+/HER2- cancer. Breast MRIs were independently reviewed by two radiologists blinded to the pathology. Discrepancies were resolved by a third radiologist. TN cancers presented with a larger tumor size (p = 0.002), higher histologic grade (<0.001), and were more likely to be unifocal (p = 0.018) compared with ER+/PR+/HER2- tumors. MRI features associated with TN tumors included mass enhancement (p = 0.026), areas of intratumoral high T2 signal intensity (p < 0.001), lobulated shape (p < 0.001), rim enhancement (p < 0.001), and smooth margins (p = 0.005). Among the TN tumors with marked necrosis, 26% showed a large central acellular zone of necrosis.

Imaging features of sporadic breast cancer in women under 40 years old: 97 cases

OBJECTIVES

To evaluate characteristic features of mammography, ultrasound and magnetic resonance imaging (MRI) of sporadic breast cancer in women <40 years and to determine correlations with pathological and biological factors.

METHODS

A retrospective review of radiological, clinicopathological and biological features of sporadic breast cancers for women under 40 years at our institution between 2007-2012 covering 91 patients. Mammography was available for 97 lesions, ultrasound for 94 and MRI for 38.

RESULTS

The most common imaging features were masses, nearly all classified BI-RADS 4 or 5. On mammography microcalcifications alone accounted for 31 %, all suspicious. There were 42.6 % luminal B, 24.5 % luminal A, 19.1 % HER2-enriched and 10.6 % triple-negative (TN) tumours by immunohistochemistry. HER2 overexpression was correlated with the presence of calcifications at mammography (P = 0.03). TN cancers more often had an oval shape and abrupt interface at ultrasound and rim enhancement on MRI. MRI features were suspicious for all cancers and rim enhancement of a mass was a significant predictor of triple-negative tumours (P = 0.01).

CONCLUSIONS

The imaging characteristics of cancers in patients under 40 years without proven gene mutations do not differ from their older counterparts, but appear correlated to phenotypic profiles, which have a different distribution in young women compared to the general population.

Correlation between imaging and molecular classification of breast cancers

The histological type of tumour according to the WHO: ductal, lobular, rare forms, is correlated with specific aspects of the imaging based on each type. This morphological classification was improved by knowledge of the molecular anomalies of breast cancers, resulting in the definition of cancer sub-groups with distinct prognoses and different responses to treatment: luminal A, luminal B, HER2 positive, basal-like, triple-negative. Studies are beginning to deal with the appearance of each sub-type in the imaging. It is now important for the radiologist to be familiar with them.

Triple-negative breast cancers: associations between imaging and pathological findings for triple-negative tumors compared with hormone receptor-positive/human epidermal growth factor receptor-2-negative breast cancers

BACKGROUND

Triple-negative (TN) breast cancers have high malignancy potential and are often characterized by early systemic relapse. Early detection is vital, but there are few comprehensive imaging reports. Here we describe mammography, ultrasound, and magnetic resonance imaging (MRI) findings of TN breast cancers, investigate the specific features of this subtype, and compare the characteristics of TN breast cancers with those of hormone receptor (HR)-positive/human epidermal growth factor receptor (HER)-2-negative breast cancers.

MATERIALS AND METHODS

From July 2009 to June 2011, mammography and ultrasound findings of 210 patients with pathologically confirmed TN (n = 105) and HR-positive/HER-2-negative breast cancers (n = 105) were retrospectively reviewed from our institutional database. Ultrasound vascularity was notified in 88 cases and elasticity scores were notified in 49 cases overall. Thirty-five patients underwent MRI (22 TN and 13 HR-positive/HER-2-negative). Mammograms, ultrasound, and MRI were reviewed according to the Breast Imaging-Reporting and Data System (BI-RADS) lexicon and classification.

RESULTS

TN breast cancers were more likely to show round, oval, or lobulated masses with indistinct margins on mammography than HR-positive/HER-2-negative breast cancers. On ultrasound, TN tumors were more likely than HR-positive/HER-2-negative breast cancers to show circumscribed or microlobulated margins and no posterior acoustic features or posterior enhancement-positive. On MRI, TN cancers exhibited suspicious aspects more often than HR-positive/HER-2-negative cancers, often with rim enhancement-positiveHER-2 (84.6% of masses were classified BI-RADS 5).

CONCLUSION

This study is the first to describe findings on mammography, ultrasound, and MRI for TN breast cancers with a matched HR-positive/HER-2-negative control group. Several distinctive morphological features of these aggressive tumors are identified that can be used for earlier diagnosis and treatment, and ultimately to improve outcomes.

Triple-negative invasive breast cancer on dynamic contrast-enhanced and diffusion-weighted MR imaging: comparison with other breast cancer subtypes

OBJECTIVES

To determine the MRI features of triple-negative invasive breast cancer (TNBC) on dynamic contrast-enhanced MR imaging (DCE-MRI) and diffusion-weighted MR imaging (DWI) in comparison with ER-positive/HER2-negative (ER+) and HER2-positive cancer (HER2+).

METHODS

A total of 271 invasive cancers in 269 patients undergoing preoperative MRI and surgery were included. Two radiologists retrospectively assessed morphological and kinetic characteristics on DCE-MRI and tumour detectability on DWI. Apparent diffusion coefficient (ADC) values of lesions were measured. Clinical and MRI features of the three subtypes were compared.

RESULTS

Compared with ER+ (n = 119) and HER2+ (n = 94), larger size, round/oval mass shape, smooth mass margin, and rim enhancement on DCE-MRI were significantly associated with TNBC (n = 58; P < 0.0001). On DWI, mean ADC value (× 10(-3) mm(2)/s) of TNBC (1.03) was higher than the mean ADC values for ER+ and HER2+ (0.89 and 0.84; P < 0.0001). There was no difference in tumour detectability (P = 0.099). Tumour size (P = 0.009), mass margin (smooth, P < 0.0001; irregular, P = 0.020), and ADC values (P = 0.002) on DCE-MRI and DWI were independent features of TNBC.

CONCLUSIONS

In addition to the morphological features, higher ADC values on DWI were independently associated with TNBC and could be useful in differentiating TNBC from ER+ and HER2+.

KEY POINTS

• Triple-negative breast cancers (TNBC) lack oestrogen/progesterone receptors and HER2 expression/amplification. • TNBCs are larger, better defined and more necrotic than conventional cancers. • On MRI, necrosis yields high T2-weighted signal intensity and ADCs. • High ADC values can be useful in diagnosing TNBC.

Radiological features of triple-negative breast cancers (73 cases)

OBJECTIVES

Triple-negative breast cancers generally occur in young women and they have the potential to be aggressive. It is important for this subtype of tumour to be detected early. We studied the appearance of 73 tumours on mammography, sonography and MRI in order to determine what specific features they showed on imaging.

PATIENTS AND METHODS

From July 2009 to December 2010, we retrospectively reviewed mammogram and sonogram images of 73 triple-negative cancers. Colour Doppler had been used to depict vascularisation in 34 cases and elastography score calculated in 17 cases. Sixteen patients had undergone MRI. The radiological description of these different modalities draws on the BI-RADS lexicon and categorisation.

RESULTS

On mammography, triple-negative cancers often presented as a round mass (59.3%) or an oval or lobulated mass (65%), with circumscribed (15%), microlobulated (12.5%), indistinct (55%) or occasionally spiculated margins (15%). On sonography, the vast majority of these cancers appeared as masses (92.8%) with occasional posterior acoustic attenuation (22.6%). MRI showed more suspicious images than the standard examinations, notably rim-enhancement (eight out of 12 masses).

CONCLUSION

. Radiological images appear as lobulated masses more readily, while on sonography posterior enhancement is shown more often than attenuation, and MRI finds rim-enhancement.