Ultrasound findings and histological features of ductal carcinoma in situ detected by ultrasound examination alone

The value of radiomics model based on ultrasound image features in the differentiation between minimal breast cancer and small benign breast masses

BACKGROUND

Female breast cancer has surpassed lung cancer as the most common cancer, and is also the main cause of cancer death for women worldwide. Breast cancer <1 cm showed excellent survival rate. However, the diagnosis of minimal breast cancer (MBC) is challenging.

OBJECTIVE

The purpose of our research is to develop and validate an radiomics model based on ultrasound images for early recognition of MBC.

METHODS

302 breast masses with a diameter of <10 mm were retrospectively studied, including 159 benign and 143 malignant breast masses. The radiomics features were extracted from the gray-scale ultrasound image of the largest face of each breast mass. The maximum relevance minimum reduncancy and recursive feature elimination methods were used to screen. Finally, 10 features with the most discriminating value were selected for modeling. The random forest was used to establish the prediction model, and the rad-score of each mass was calculated. In order to evaluate the effectiveness of the model, we calculated and compared the area under the curve (AUC) value, sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the model and three groups with different experience in predicting small breast masses, and drew calibration curves and decision curves to test the stability and consistency of the model.

RESULTS

When we selected 10 radiomics features to calculate the rad-score, the prediction efficiency was the best, the AUC values for the training set and testing set were 0.840 and 0.793, which was significantly better than the insufficient experience group (AUC = 0.673), slightly better than the moderate experience group (AUC = 0.768), and was inferior to the experienced group (AUC = 0.877). The calibration curve and decision curve also showed that the radiomics model had satisfied stability and clinical application value.

CONCLUSION

The radiomics model based on ultrasound image features has a satisfied predictive ability for small breast masses, and is expected to become a potential tool for the diagnosis of MBC, and it is a zero cost (in terms of patient participation and imaging time).

Artificial intelligence for non-mass breast lesions detection and classification on ultrasound images: a comparative study

BACKGROUND

This retrospective study aims to validate the effectiveness of artificial intelligence (AI) to detect and classify non-mass breast lesions (NMLs) on ultrasound (US) images.

METHODS

A total of 228 patients with NMLs and 596 volunteers without breast lesions on US images were enrolled in the study from January 2020 to December 2022. The pathological results served as the gold standard for NMLs. Two AI models were developed to accurately detect and classify NMLs on US images, including DenseNet121_448 and MobileNet_448. To evaluate and compare the diagnostic performance of AI models, the area under the curve (AUC), accuracy, specificity and sensitivity was employed.

RESULTS

A total of 228 NMLs patients confirmed by postoperative pathology with 870 US images and 596 volunteers with 1003 US images were enrolled. In the detection experiment, the MobileNet_448 achieved the good performance in the testing set, with the AUC, accuracy, sensitivity, and specificity were 0.999 (95%CI: 0.997-1.000),96.5%,96.9% and 96.1%, respectively. It was no statistically significant compared to DenseNet121_448. In the classification experiment, the MobileNet_448 model achieved the highest diagnostic performance in the testing set, with the AUC, accuracy, sensitivity, and specificity were 0.837 (95%CI: 0.990-1.000), 70.5%, 80.3% and 74.6%, respectively.

CONCLUSIONS

This study suggests that the AI models, particularly MobileNet_448, can effectively detect and classify NMLs in US images. This technique has the potential to improve early diagnostic accuracy for NMLs.

Ultrasound diagnosis of non-mass MRI-detected lesions

Magnetic resonance imaging (MRI)-detected lesions are often category 2 or 3 lesions on initial ultrasound examination. In addition, in the case of new non-mass lesions detected on MRI, one would expect to find lesions with ductal dilatation with minimal secretory accumulation, single short lesions with ductal dilatation, cyst-like lesions less than 5 mm in size, mammary gland-like lesions less than 8 mm in size, and very indistinct lesions. Detection is expected to be even more difficult. Currently, there are no clear uniform criteria for the indication of second-look ultrasonography (US) for MRI-detected lesions, so it is not possible to make a general comparison, but recent studies have indicated that the ratio of mass to non-mass MRI-detected lesions is 7:3. And it has been pointed out that the percentage of malignancy is about 30% for each. Before about 2012, the US detection rate was about 70%, and MRI-guided biopsies of undetected lesions showed a small percentage of malignant lesions. Therefore, some observers believe that lesions not detected on US should be followed up, while others believe that MRI-guided biopsy should be performed. Recently, however, the use of surrounding anatomical structures as landmarks for second-look US has increased the detection rate to as high as 87-99%, and the percentage of malignancy remains the same. In addition, recent surveillance of high-risk breast cancer requires careful management of MRI-detected lesions. In this review, we will discuss the literature on MRI-detected lesions and describe ultrasound techniques to accurately detect small lesions and reliably reveal pale lesions based on their structural differences from their surroundings.

The Japan Society of Ultrasonics in Medicine guidelines on non-mass abnormalities of the breast

It is possible to appropriately diagnose non-mass abnormalities by elucidating ultrasound non-mass abnormality findings and sharing the concept. If non-mass abnormalities can be diagnosed early, the number of curable cases could increase, leading to fewer breast cancer deaths. The Japan Society of Ultrasonics in Medicine (JSUM) Terminology/Diagnostic Criteria Committee has classified non-mass abnormalities into five subtypes: hypoechoic area in the mammary gland, abnormalities of the ducts, architectural distortion, multiple small cysts, and echogenic foci without a hypoechoic area. We herein define the findings for each of these subtypes and present a summary of the JSUM guidelines on non-mass abnormalities of the breast generated based on those findings.

Features of ductal carcinoma in situ ultrasound images

Ultrasound images of ductal carcinoma in situ (DCIS) show a wide range of variations from mass to non-mass lesions. This article describes the characteristics of ultrasound images of DCIS based on the BC-02 study conducted by The Japanese Association of Breast and Thyroid Sonology (JABTS). In the BC-02 study, ultrasound images of 705 DCIS cases were classified by imaging findings. The results showed that non-mass abnormalities accounted for 60% of all lesions and masses for 40%. Looking at each subclassification, hypoechoic areas in the mammary gland were the most common (50% of the total), followed by solid masses (31%), mixed masses (9%), and abnormalities of the ducts (8%). These four classifications accounted for 98% of the total. Echogenic foci without a hypoechoic area, architectural distortion, and clustered microcysts were very rare, accounting for about 1% of the total. The ultrasound images of DCIS were characterized by a wide range of variations from masses to non-masses abnormalities, with hypoechoic areas in the mammary gland being the most common, followed by solid masses.

Non-mass Breast Lesions: Could Multimodal Ultrasound Imaging Be Helpful for Their Diagnosis?

Objective: To develop a prediction model for discriminating malignant from benign breast non-mass-like lesions (NMLs) using conventional ultrasound (US), strain elastography (SE) of US elastography and contrast-enhanced ultrasound (CEUS). Methods: A total of 101 NMLs from 100 patients detected by conventional US were enrolled in this retrospective study. The characteristics of NMLs in conventional US, SE and CEUS were compared between malignant and benign NMLs. Histopathological results were used as the reference standard. Binary logistic regression analysis was performed to identify the independent risk factors. A multimodal method to evaluate NMLs based on logistic regression was developed. The diagnostic performance of conventional US, US + SE, US + CEUS and the combination of these modalities was evaluated and compared. Results: Among the 101 lesions, 50 (49.5%) were benign and 51 (50.5%) were malignant. Age ≥45 y, microcalcifications in the lesion, elasticity score >3, earlier enhancement time and hyper-enhancement were independent diagnostic indicators included to establish the multimodal prediction method. The area under the receiver operating characteristic curve (AUC) of US + SE + CEUS was significantly higher than that of US (p < 0.0001) and US + SE (p < 0.0001), but there was no significant difference between the AUC of US + SE + CEUS and the AUC of US + CEUS (p = 0.216). Conclusion: US + SE + CEUS and US + CEUS could significantly improve the diagnostic efficiency and accuracy of conventional US in the diagnosis of NMLs.

Ultrasound evaluation of ductal carcinoma in situ of the breast

PURPOSE

To assess the role of ultrasound (US) in detecting and characterizing ductal carcinoma in situ (DCIS) of the breast and to investigate the correlation between ultrasonographic and biological features of DCIS.

METHODS

In total, 171 patients (mean age 44; range 39-62) with 178 lesions were retrospectively evaluated by two independent radiologists searching for US mass or non-mass lesions. Immunohistochemistry analysis was performed to determine estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expression. The US detection rate and pattern distribution among the lesion types were evaluated. The χ² test was used to evaluate the correlation between the US findings and the biological factors. Statistical significance was indicated by p values < 0.05. Inter-observer agreement was calculated by Kohen's k test.

RESULTS

US detected 35% (63/178) of all lesions. Fifty-two (83%) lesions were classified as mass lesions, and 11 (17%) as non-mass lesions (p < 0.0001). Among the mass lesions, the most common shape was irregular (79%; p < 0.0001), with 45 (87%) lesions having indistinct margins. Hypoechogenicity was the most common echo pattern (49 cases, 94%; p < 0.0001). Microcalcifications were found in 23 cases (37%; p = 0.004) and were associated with mass lesions in 15 cases (65%) and with non-mass lesions in 8 cases (35%) (p = 0.21). An almost perfect inter-observer agreement (k = 0.87) was obtained between the two radiologists. A significant ER expression was found in mass lesions (83%; p < 0.0001), with no significant PR (p = 0.89) or HER2 expression (p = 0.81). Among the lesions with microcalcifications, only 7 out of 23 cases (30%) were positive for HER2 (p = 0.09).

CONCLUSION

DCIS represents a heterogeneous pathological process with variable US appearance (mass-like, non-mass-like, or occult). The most common US finding is represented by mass-type, hypoechogenic lesions with indistinct margins. A significant ER expression exists among mass-type lesions, while microcalcifications seem not to be associated with HER2 expression.

Ultrasonographic features of ductal carcinoma in situ: analysis of 219 lesions

Background

The purpose of this paper is to clarify the ultrasonographic features and classification of ductal carcinoma in situ (DCIS), and to evaluate the ability of ultrasonography in the prediction of DCIS.

Methods

The clinical data, gray-scale ultrasound images and pathological results of 219 DCIS lesions that detected in 203 consecutive patients who underwent ultrasonography and surgery in our hospital from January 1, 2014 to December 31, 2019 were collected retrospectively. Ultrasonographic features and classification of DCIS were summarized, and the accuracy of ultrasonography in predicting different ultrasonographic findings of DCIS were compared.

Results

Among the 219 DCIS lesions, 91 (41.6%) presented as mass-like lesions and 128 (58.4%) were non-mass-like lesions. For the 91 mass-like DCIS lesions, 79 were hypoechoic solid masses, 12 were cystic-solid structures. For the 128 non-mass-like DCIS lesions, 114 were hypoechoic areas, 10 were ductal dilatation accompanied with intraductal solid components, and 4 were multiple punctate echogenic foci only. The diagnostic accuracy of ultrasound for the 219 DCIS lesions was 81.7% (179/219). The diagnostic accuracy of mass-like DCIS lesions was 90.1% (82/91), which was significantly higher than that in non-mass-like DCIS lesions [75.8% (97/128), P=0.007]. The diagnostic accuracy of hypoechoic solid masses was significantly higher than those of the other ultrasonographic findings (P=0.002). Ducts abnormalities were detected in 45 (20.5%) lesions and punctate echogenic foci in 134 (61.2%) lesions. The diagnostic accuracy of lesions with ducts abnormalities was 93.3% (42/45), which was significantly higher than that in lesions without ducts abnormalities [78.7% (137/174), P=0.024]. The diagnostic accuracy of lesions with punctate echogenic foci was 92.5% (124/134), which was significantly higher than that in lesions without punctate echogenic foci [64.7% (55/85), P=0.000].

Conclusions

DCIS lesions can effectively be recognized as mass-like lesions and non-mass-like lesions by ultrasound. Hypoechoic areas and hypoechoic solid masses were the most common ultrasonographic features of DCIS. Ducts abnormalities and punctate echogenic foci were helpful for the diagnosis of DCIS.

Characteristics of ultrasonographic images of ductal carcinoma in situ with abnormalities of the ducts

Purpose

Although the number of ductal carcinoma in situ (DCIS) cases has increased with the spread of breast cancer screening in Japan, there are very few reports that summarize ultrasound image features of DCIS. The Japan Association of Breast and Thyroid Sonology (JABTS) investigated the incidence of DCIS with masses and non-mass abnormalities and the characteristics of US images in a retrospective, multicenter, observational study (JABTS BC-02 study). The purpose of this report is to clarify the proportion of DCIS with abnormalities of the ducts with each ultrasound finding and the characteristics of US images.

Methods

The JABTS BC-02 study population was comprised of patients who were examined by ultrasonography, underwent surgery, and were histopathologically diagnosed with DCIS at each study site between January 2008 and December 2012. The US images of DCIS and pathology and clinical information were retrospectively collected from 16 institutions in Japan. The US images were evaluated by 22 experts on the Central Image Interpretation Committee of JABTS.

Results

Abnormalities of the ducts were noted in 78 (10.5%) of 705 US images of DCIS. Of the 78 cases, the distribution of abnormalities of the ducts was focal or segmental. The second characteristic was the presence of internal echoes in dilated ducts. All cases were accompanied by intraductal solid echoes, and 40 cases (51.3%) were accompanied by echogenic foci. In addition, intraductal solid echoes were continuous or multiple in 72 cases (92.4%), and the shape of the solid echoes was broad-based and/or irregular in 62 cases (79.5%).

Conclusion

DCIS cases with duct abnormalities on ultrasound were investigated in this study. The important characteristics were as follows: (1) the distribution of ductal dilatation was focal or segmental, (2) solid parts were present in the dilated ducts, (3) the distribution of internal echoes was continuous or multiple, (4) the shape of solid echoes was broad-based and/or irregular, and (5) internal echoes were sometimes accompanied by echogenic foci. Accurate evaluation of these findings may be useful for diagnosing DCIS. Although the duct abnormalities are included in “ASSOCIATED FEATURES” in ACR BI-RADS ATLAS (USA), we emphasize that this concept is very important for understanding US characteristics of DCIS.

Ductal Carcinoma in Situ: Current Concepts in Biology, Imaging, and Treatment

Ductal carcinoma in situ (DCIS) of the breast is a group of heterogeneous epithelial proliferations confined to the milk ducts that nearly always present in asymptomatic women on breast cancer screening. A stage 0, preinvasive breast cancer, increased detection of DCIS was initially hailed as a means to prevent invasive breast cancer through surgical treatment with adjuvant radiation and/or endocrine therapies. However, controversy in the medical community has emerged in the past two decades that a fraction of DCIS represents overdiagnosis, leading to unnecessary treatments and resulting morbidity. The imaging hallmarks of DCIS include linearly or segmentally distributed calcifications on mammography or nonmass enhancement on breast MRI. Imaging features have been shown to reflect the biological heterogeneity of DCIS lesions, with recent studies indicating MRI may identify a greater fraction of higher-grade lesions than mammography does. There is strong interest in the surgical, imaging, and oncology communities to better align DCIS management with biology, which has resulted in trials of active surveillance and therapy that is less aggressive. However, risk stratification of DCIS remains imperfect, which has limited the development of precision therapy approaches matched to DCIS aggressiveness. Accordingly, there are opportunities for breast imaging radiologists to assist the oncology community by leveraging advanced imaging techniques to identify appropriate patients for the less aggressive DCIS treatments.

Long-term Surveillance of Ductal Carcinoma in Situ Detected with Screening Mammography versus US: Factors Associated with Second Breast Cancer

Background The relationship between method of breast cancer screening (mammography or US) and survival outcome in patients with screening-detected ductal carcinoma in situ (DCIS) has not been determined. Purpose To investigate whether different methods of breast cancer screening are associated with different survival outcomes in patients with screening-detected DCIS and to evaluate clinical-pathologic and imaging factors associated with second breast cancer. Materials and Methods We retrospectively identified women who underwent surgery to treat DCIS initially detected with screening mammography or US between July 2004 and December 2011 in a single institution. Overall survival (OS) and disease-free survival (DFS) were assessed. Factors associated with second breast cancer (invasive carcinoma or DCIS) were found with multivariable Cox proportional hazards regression analysis. Subgroups were analyzed according to screening method. Results A total of 814 women (median age, 47 years; age range, 25-81 years) were included; 627 underwent treatment for screening mammography-detected DCIS (mammography-detected group), and 187 underwent treatment for screening US-detected DCIS (US-detected group). During follow-up (median, 7 years; interquartile range, 5-8 years), 26 ipsilateral and 26 contralateral second breast cancers (6.4%, 52 of 814) were found, with 44 in the mammography-detected group and eight in the US-detected group. The overall 5-year OS and DFS rates were 100% and 95.3%, respectively. DFS rates did not differ according to screening method (P = .21, 5-year DFS rates were 94.9% in the mammography-detected group and 96.5% in the US-detected group). In the mammography-detected group, higher nuclear grade (intermediate grade: hazard ratio [HR], 5.7; 95% confidence interval [CI]: 1.3, 24.3; P = 0.02) (high grade: HR, 8.0; 95% CI: 1.9, 34.2; P = .01) and dense breast (HR, 3.5; 95% CI: 1.1, 11.4; P = 0.04) were associated with second breast cancer. In the US-detected group, human epidermal growth factor receptor 2 positivity was associated with second breast cancer (HR, 9.2; 95% CI: 2.2, 38.5; P = .002). Conclusion Disease-free survival of patients who underwent treatment for screening-detected ductal carcinoma in situ (DCIS) did not differ according to screening detection method. In patients with screening mammography-detected DCIS, higher nuclear grade and dense breast were associated with second breast cancer, and in patients with screening US-detected DCIS, human epidermal growth factor 2 positivity was associated with second breast cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Fowler in this issue.

Ultrasonographic features of pure ductal carcinoma in situ of the breast: correlations with pathologic features and biological markers

Purpose

The purpose of this study was to evaluate the ultrasonographic features of pure ductal carcinoma in situ (DCIS) of the breast and to evaluate the correlations of ultrasonographic features with pathologic and biological features.

Methods

A total of 141 lesions in 138 women with pure DCIS who underwent preoperative breast ultrasonography were retrospectively reviewed. Ultrasonographic features were analyzed using the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS) ultrasonography lexicon and the diagnostic criteria of the Japan Society of Ultrasonics in Medicine. Pathologic features including the nuclear grade and presence of comedonecrosis were evaluated. Biological markers including estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) status, as well as the Ki-67 index, were recorded. Ultrasonographic features were compared with pathologic findings and biological markers using the chi-square test. P-values of <0.05 were considered to indicate statistical significance.

Results

Of the 141 lesions, 75 (53.2%) were mass lesions, 56 (39.7%) were non-mass lesions, and 10 (7.1%) were not visible. The most common feature of the mass pattern was a mass with irregular shape (32.6%), an indistinct margin (27.7%), and hypoechogenicity (37.6%). Microcalcifications were observed in 48 cases (36.6%) as an associated feature. Calcifications outside of a mass were more common than calcifications within a mass. Ultrasonographic microcalcifications and ductal changes were frequently observed in non-mass lesions. Ultrasonographic non-mass lesions were associated with high-grade DCIS (P=0.004) and the presence of comedonecrosis (P=0.006). Microcalcifications were significantly associated with high-grade DCIS (P<0.001), the presence of comedonecrosis (P<0.001), an elevated Ki-67 (P<0.001), and HER2 positivity (P=0.003).

Conclusion

The most common ultrasonographic feature of pure DCIS was an irregular, hypoechoic mass with an indistinct margin. Ultrasonographic microcalcifications and ductal changes were more frequent in non-mass lesions, which were correlated with poor prognostic factors, such as a high nuclear grade, comedonecrosis, HER2 positivity, and an elevated Ki-67 index.

Ultrasound Image Classification of Ductal Carcinoma In Situ (DCIS) of the Breast: Analysis of 705 DCIS Lesions

The Japan Association of Breast and Thyroid Sonology (JABTS) proposed, in 2003, a conceptual classification system for non-mass abnormalities to be applied in addition to the conventional concept of masses, to facilitate detecting ductal carcinoma in situ (DCIS) lesions. The aim of this study was to confirm the utility of this system and to clarify the distribution of these findings in DCIS lesions. Data on 705 surgically treated DCIS lesions from 16 institutions in Japan were retrospectively reviewed. All 705 DCIS lesions could be classified according to the JABTS classification system. The most frequent findings were hypo-echoic areas in the mammary gland (48.6%), followed by solid masses (28.0%) and duct abnormalities (10.2%) or mixed masses (8.1%). Distortion (1.3%), clustered microcysts (1.4%) and echogenic foci without a hypo-echoic area (2.5%) were uncommon. These results suggest that the concept of non-mass abnormalities is useful in detecting DCIS lesions.

Breast Cancer Detection in a Screening Population: Comparison of Digital Mammography, Computer-Aided Detection Applied to Digital Mammography and Breast Ultrasound

Purpose

We aimed to compare the detection of breast cancer using full-field digital mammography (FFDM), FFDM with computer-aided detection (FFDM+CAD), ultrasound (US), and FFDM+CAD plus US (FFDM+CAD+US), and to investigate the factors affecting cancer detection.

Methods

In this retrospective study conducted from 2008 to 2012, 48,251 women underwent FFDM and US for cancer screening. One hundred seventy-one breast cancers were detected: 115 invasive cancers and 56 carcinomas in situ. Two radiologists evaluated the imaging findings of FFDM, FFDM+CAD, and US, based on the Breast Imaging Reporting and Data System lexicon of the American College of Radiology by consensus. We reviewed the clinical and the pathological data to investigate factors affecting cancer detection. We statistically used generalized estimation equations with a logit link to compare the cancer detectability of different imaging modalities. To compare the various factors affecting detection versus nondetection, we used Wilcoxon rank sum, chi-square, or Fisher exact test.

Results

The detectability of breast cancer by US (96.5%) or FFDM+CAD+US (100%) was superior to that of FFDM (87.1%) (p=0.019 or p<0.001, respectively) or FFDM+ CAD (88.3%) (p=0.050 or p<0.001, respectively). However, cancer detectability was not significantly different between FFDM versus FFDM+CAD (p=1.000) and US alone versus FFDM+CAD+US (p=0.126). The tumor size influenced cancer detectability by all imaging modalities (p<0.050). In FFDM and FFDM+CAD, the nondetecting group consisted of younger patients and patients with a denser breast composition (p<0.050). In breast US, carcinoma in situ was more frequent in the nondetecting group (p=0.014).

Conclusion

For breast cancer screening, breast US alone is satisfactory for all age groups, although FFDM+ CAD+US is the perfect screening method. Patient age, breast composition, and pathological tumor size and type may influence cancer detection during screening.

Additional diagnostic value of shear-wave elastography and color Doppler US for evaluation of breast non-mass lesions detected at B-mode US

OBJECTIVE

To evaluate the diagnostic value of shear-wave elastography (SWE) and colour Doppler ultrasound (US) for evaluation of breast non-mass lesions (NMLs) detected by B-mode US.

METHODS

This retrospective study enrolled 116 NMLs (42 benign, 74 malignant). For each lesion, B-mode US, SWE and colour Doppler US were performed. Mean elasticity (E mean), maximum elasticity (E max) and vascularity were assessed by SWE and Doppler US. Diagnostic performances of B-mode US, SWE and Doppler US were calculated to differentiate benign and malignant NMLs.

RESULTS

In benign NMLs, average E mean and E max were lower, and low vascularity (no flow or only one vessel flow) was more frequent (P < 0.001). When BI-RADS category 4a NMLs were downgraded to category 3 with 'E mean of 85.1 kPa or less' and/or 'low vascularity', specificities increased (69.0-90.5 %; P < 0.001), without significant loss in sensitivities (97.3-100 %). When these 4a NMLs were downgraded by the combination of SWE and Doppler US, all downgraded NMLs (59.3 %, 19/32) were confirmed as benign.

CONCLUSIONS

Addition of SWE and colour Doppler US to B-mode US improved diagnostic performances in differentiating benign and malignant NMLs. This study suggests that the combination of SWE and colour Doppler may help patients with BI-RADS category 4a NMLs avoid unnecessary biopsies.

KEY POINTS

• B-mode US features of malignant and benign NMLs may overlap. • SWE and colour Doppler provides useful information about breast NMLs. • SWE and colour Doppler may decrease unnecessary biopsies of breast NMLs.

Correlation between sonographic findings and clinicopathologic and biologic features of pure ductal carcinoma in situ in 691 patients

OBJECTIVE

The objective of our study was to compare the sonographic features of pure ductal carcinoma in situ (DCIS) lesions with the initial clinical presentation and histopathologic findings.

MATERIALS AND METHODS

The images and records of 691 patients with pure DCIS who underwent preoperative mammography and whole-breast sonography as part of staging workup in a single institution from January 1, 1996, through July 31, 2009, were reviewed. The BI-RADS sonography lexicon was used when reviewing the sonographic studies. Histopathologic features recorded included estrogen receptor (ER) status, nuclear grade, and presence or absence of comedonecrosis. Statistical comparisons were made using the Student t test, chi-square test, Fisher exact test, Kruskal-Wallis or Wilcoxon rank sum test, multiple logistic regression analysis, and Pearson correlation coefficient.

RESULTS

A total of 304 (44%) tumors were visible on mammography and sonography; 315 (46%), on mammography only; 58 (8%), on sonography only; and 14 (2%), on neither mammography nor sonography. The most common sonographic appearance of DCIS was an irregular hypoechoic mass with indistinct margins and normal posterior features that was indistinguishable from invasive carcinoma. Patients with symptomatic high-nuclear-grade DCIS, dense breasts, and comedonecrosis were younger and had larger tumors on sonography than asymptomatic women with nondense breasts and low-nuclear-grade and noncomedo DCIS. Women with ER-negative DCIS were older and had larger tumors on sonography than women with ER-positive DCIS. ER-negative tumors were more frequently visible on sonography than ER-positive tumors (p=0.007). High-grade DCIS (p<0.0001) and comedo DCIS (p<0.0001) presented more frequently as microcalcifications, architectural distortion, and ductal changes on sonography than low-grade DCIS or noncomedo DCIS.

CONCLUSION

Of the 691 pure DCIS lesions, 362 (52%) were visible on sonography and presented most commonly as a mass. Lesion visibility of DCIS on sonography was not related to nuclear grade or the presence of comedonecrosis.

Diagnostic evaluation of ductal carcinoma in situ of the breast: ultrasonographic, mammographic and histopathologic correlations

The aims of the study described here were to illustrate the spectrum of ultrasonographic features of ductal carcinoma in situ (DCIS) and to evaluate the ability of ultrasonography (US) to predict the grade and recurrence of DCIS on the basis of mammographic and histopathologic findings. We retrospectively evaluated the ultrasonographic features of 129 DCIS lesions from 127 consecutive women and compared these with their mammographic and histopathologic features. The mean size of DCISs on ultrasonography and mammography (MMG) was 3.67 ± 1.40 and 4.00 ± 1.74 cm, respectively, which do not differ statistically (p = 0.09). Despite the statistical difference in Breast Imaging Reporting and Data System (BI-RADS) classification on US and MMG (p = 0.000), the median BI-RADS classification is category 4c on both US and MMG (p = 0.01). There was no statistically significant difference in the distribution of microcalcification on MMG and US. Clusters <5 mm in greatest diameter are easily seen on MMG. At US, a scattered/linear distribution on MMG had a higher level of visibility than clustered distribution on MMG. The correlation between tumor size and DCIS with micro-invasion evaluated using US is higher than that obtained using MMG (p = 0.001 and 0.024, respectively). When US was used for the detection of DCIS, diagnostic accuracy was significantly associated with higher Van Nuys groups, the presence of micro-invasion and comedo carcinoma (p = 0.000, 0.022 and 0.011, respectively). However, mammographic diagnostic accuracy was found not to associate with higher Van Nuys groups, the presence of micro-invasion and comedo carcinoma (p = 0.054, 0.093 and 0.256, respectively). Ultrasonography may play an important role both in detecting DCIS and in evaluating its histopathologic features. Detection of DCIS using MMG alone may be suboptimal for patients with dense breasts, especially among Chinese women.

Breast carcinomas: variations in sonoelastographic appearance

Background

This study assessed factors influencing the sonoelastographic presentation of breast carcinoma.

Methods

A prospective collaborative study was conducted by the Santa Casa de São Paulo and CTC-Center, on 540 breast lesions in women referred for percutaneous breast biopsy. Eighty-four carcinomas showing lesions on ultrasonography were included. These lesions were classified into four sonoelastographic scores, where scores of 1, 2, and 3 were considered false-negative, and a score of 4 was considered true-positive. Scores were compared against histopathologic results, which were divided into two groups, ie, soft lesions (group 1) and hard lesions (group 2). False-negative and true-positive results were also assessed for variation according to patient age and mean lesion diameter.

Results

Of the 84 lesions studied, nine yielded false-negative results on sonoelastography and 75 yielded true-positive results. In terms of histopathologic classification, eight were assigned to group 1 and 76 to group 2. The chi-squared test showed a correlation between sonoelastographic scores and histopathologic lesion type. No statistically significant differences were observed according to patient age or largest lesion diameter.

Conclusion

Our results revealed an association between sonoelastographic presentation of breast lesions and histology. False-negative results on sonoelastography were influenced by histologic type of lesion and not by lesion size or patient age.

Breast ultrasonography: state of the art

Ultrasonography (US) is an indispensable tool in breast imaging and is complementary to both mammography and magnetic resonance (MR) imaging of the breast. Advances in US technology allow confident characterization of not only benign cysts but also benign and malignant solid masses. Knowledge and understanding of current and emerging US technology, along with the application of meticulous scanning technique, is imperative for image optimization and diagnosis. The ability to synthesize breast US findings with multiple imaging modalities and clinical information is also necessary to ensure the best patient care. US is routinely used to guide breast biopsies and is also emerging as a supplemental screening tool in women with dense breasts and a negative mammogram. This review provides a summary of current state-of-the-art US technology, including elastography, and applications of US in clinical practice as an adjuvant technique to mammography, MR imaging, and the clinical breast examination. The use of breast US for screening, preoperative staging for breast cancer, and breast intervention will also be discussed.

Potential role of shear-wave ultrasound elastography for the differential diagnosis of breast non-mass lesions: preliminary report

OBJECTIVES

To report our preliminary experience with shear-wave elastography (SWE) for non-mass lesions (NMLs) in the breast and suggest a potential ancillary role of SWE for BI-RADS Category 4a NMLs in reducing the number of unnecessary benign biopsies.

METHODS

A total of 310 breast lesions in 286 consecutive women who had been scheduled for US-guided automated gun biopsy or vacuum-assisted biopsy between June and December 2012 were initially included in this study. Finally, 33 women with 34 breast lesions classified as NMLs constituted our study population. Diagnostic performances of each quantitative SWE parameter were calculated. Histological diagnosis was used as a reference standard.

RESULTS

Among the 34 breast NMLs, 22 (65%) were benign and 12 (35%) were malignant. Emean value with cut-off set at 41.6 kPa had the highest Az value 0.788 (95% CI, 0.625-0.951), showing sensitivity of 83.3% and specificity of 68.2%. By applying an Emean value of 41.6 kPa or less as a criterion for downgrading soft BI-RADS category 4a NMLs to category 3 NMLs, 15 unnecessary biopsies could have been eliminated from the 19 BI-RADS category 4a lesions (79%).

CONCLUSIONS

SWE features could increase positive predictive values and reduce unnecessary benign biopsies of category 4a NMLs.

KEY POINTS

• Ultrasound elastography is increasingly used to assess the stiffness of breast lesions • Shear-wave elastography provides useful information about non-mass breast lesions • Shear-wave elastography may render some biopsies of non-mass breast lesions unnecessary.

A prospective study about abnormal ductal dilatations without associated masses on breast US: what is the significance for us?

RATIONALE AND OBJECTIVES

Ductal changes are described as a finding of surrounding tissues in breast masses according to the Breast Imaging Reporting and Data System - Ultrasound. However, ductal changes are often found as an isolated finding without a mass on ultrasound. The purpose of this study was to investigate the clinical significance of abnormal ductal dilatations without masses on breast ultrasound.

MATERIALS AND METHODS

From August 2006 to August 2008, 75 pathologically verified pure ductal dilatations without associated masses on breast ultrasound were collected. Ultrasound findings including the diameter and length of the duct, the presence of ductal wall thickening and intraluminal content, the echo pattern of intraluminal content, and distribution were evaluated. The ultrasound findings were correlated with clinical and pathologic features, and radiologic differences between benign and malignant lesions were assessed using Fisher's exact tests.

RESULTS

Of the 75 cases with abnormal ductal dilatations, seven (9%) were malignant, and four (5%) were atypical ductal hyperplasia. Ductal dilatations were longer in malignancies than in benign lesions (P < .05). Ductal wall thickening was more frequent in malignancies (100%) and atypical ductal hyperplasia (50%) than in other benign lesions (3%) (P < .05). Hypoechoic intraluminal content was more common in malignancies (86%) and atypical ductal hyperplasia (50%) than in other benign lesions (8%) (P < .05). Furthermore, a segmental distribution was more frequent in malignancies (43%) than in benign lesions (1%). Clinical symptoms were also frequent in malignancies (86%) than in benign lesions (4%) (P < .05).

CONCLUSIONS

Abnormal ductal dilatations without masses have a 9% malignancy rate, and these would be recommended to undergo biopsy as suspicious abnormalities according to Breast Imaging Reporting and Data System - Ultrasound. Ultrasound has an essential role in the assessment of abnormal ducts for distinguishing benign and malignant ductal changes.

Characteristics of breast cancers detected by ultrasound screening in women with negative mammograms

Screening ultrasound (US) can increase the detection of breast cancer. However, little is known about the clinicopathologic characteristics of breast cancers detected by screening US. A search of the database for patients with breast cancer yielded a dataset in 6837 women who underwent breast surgery at Seoul National University Hospital (Korea). Of 6837 women, 1047 were asymptomatic and had a non-palpable cancer. Two hundred fifty-four women with 256 cancers detected by US (US-detected cancer) and 793 women with 807 cancers detected by mammography (MG-detected cancer) were identified. The imaging, clinicopathologic, and molecular data were reviewed. Univariate and multivariate analyses were carried out. Women with US-detected cancer were younger and were more likely to undergo breast-conserving surgery and to have node-negative invasive cancer (P < 0.0001). By multivariate analysis, the significant independent characteristics were tumor size, mammographic density, final assessment category according to the American College of Radiology Breast Imaging Reporting and Data System, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and molecular subtype. Compared to tumors that were > 2 cm in size, tumors that were ≤ 1 cm in size were 2.2-fold more likely to be US-detected cancers (P = 0.02). Compared to the luminal A subtype tumors (estrogen receptor [ER]+, PR+, HER2-), luminal B subtype tumors (ER+, PR+, HER2+) were less likely to be in the US-detected cancer group (P < 0.01). Women with dense breasts were more likely to have US-detected cancer (P < 0.01) versus those with non-dense breasts. Screening US-detected cancers were less likely to be diagnosed as category 5 instead of category 4 (P < 0.01). In conclusion, women with US-detected breast cancer are more likely to have small-sized invasive cancer and more likely associated with the luminal A subtype.

The impact of preoperative magnetic resonance imaging on surgical treatment and outcomes for ductal carcinoma in situ

BACKGROUND

Although magnetic resonance imaging (MRI) is a useful imaging modality for invasive cancer, its role in preoperative surgical planning for ductal carcinoma in situ (DCIS) has not been established. We sought to determine whether preoperative MRI affects surgical treatment and outcomes in women with pure DCIS.

PATIENTS AND METHODS

We reviewed consecutive records of women diagnosed with pure DCIS on core biopsy between 2000 and 2007. Patient characteristics, surgical planning, and outcomes were compared between patients with and without preoperative MRI. Multivariable regression was performed to determine which covariates were independently associated with mastectomy or sentinel lymph node biopsy (SLNB).

RESULTS

Of 149 women diagnosed with DCIS, 38 underwent preoperative MRI. On univariate analysis, patients undergoing MRI were younger (50 years vs. 59 years; P < .001) and had larger DCIS size on final pathology (1.6 cm vs. 1.0 cm; P = .007) than those without MRI. Mastectomy and SLNB rates were significantly higher in the preoperative MRI group (45% vs. 14%, P < .001; and 47% vs. 23%, P = .004, respectively). However, there were no differences in number of re-excisions, margin status, and margin size between the two groups. On multivariate analysis, preoperative MRI and age were independently associated with mastectomy (OR, 3.16, P = .018; OR, 0.95, P = .031, respectively), while multifocality, size, and family history were not significant predictors.

CONCLUSION

We found a strong association between preoperative MRI and mastectomy in women undergoing treatment for DCIS. Additional studies are needed to examine the increased rates of mastectomy as a possible consequence of preoperative MRI for DCIS.

Contrast-enhanced ultrasonographic findings of different histopathologic types of breast cancer

BACKGROUND

The new application of contrast-enhanced ultrasonography (CEUS) in the diagnosis of breast masses has evolved quickly only in recent years. Nevertheless, mixed results owing to the overlap in characteristics of benign and malignant lesions are simultaneously discovered by most studies, partially attributed to different histopathologic characteristics of breast cancer.

PURPOSE

To explore the characteristics of different histopathologic types of breast cancer at real-time gray-scale CEUS and evaluate its diagnostic value.

MATERIAL AND METHODS

One hundred and one histopathologically confirmed malignant lesions were included. We retrospectively reviewed the contrast-enhanced ultrasonographic findings including morphologic features, quantitative parameters, and correlated them with histopathology. True-positive rate was calculated to assess the diagnostic performance of CEUS.

RESULTS

The 101 malignancies displayed irregular shape (72 [71%]), poorly-defined margin (73 [72%]), penetrating or tortuous surrounding vessels (79 [78%]), heterogeneous enhancement (84 [83%]), including focal perfusion defects (24 [24%]). For each histopathologic type, 87% (58/67) of invasive ductal carcinoma (IDC) showed heterogeneous enhancement. Of all the 24 perfusion defects, IDC account for 88% (21/24). Low average peak intensity (PI) of 4.9 was detected in this type. Ductal carcinoma in situ (DCIS) excellently showed the features of irregular shape (82% [14/17]), poorly-defined margin (82% [14/17]), heterogeneous enhancement (94% [16/17]). While 83% (5/6) of medullary carcinoma exhibited regular shape, well-defined margin, homogenous enhancement, and high average PI value of 9.6. Invasive lobular carcinoma showed similar enhancement pattern to that of IDC. Intraductal papillary carcinoma displayed high average PI value of 8.1. The overall true-positive rate for conventional US and CEUS was 88%, 86%, respectively. DCIS, medullary carcinoma, and intraductal papillary carcinoma achieved an improved true-positive rate (94%, 100% and 100%, respectively).

CONCLUSION

The imaging characteristics of CEUS are variable in different histopathologic types of breast cancer. CEUS does not appear to be superior to conventional ultrasound as a diagnostic tool overall, however, it is a useful adjunct to conventional ultrasound in diagnosing some special types of breast cancer.

Computer-aided diagnosis for the classification of breast masses in automated whole breast ultrasound images

New automated whole breast ultrasound (ABUS) machines have recently been developed and the ultrasound (US) volume dataset of the whole breast can be acquired in a standard manner. The purpose of this study was to develop a novel computer-aided diagnosis system for classification of breast masses in ABUS images. One hundred forty-seven cases (76 benign and 71 malignant breast masses) were obtained by a commercially available ABUS system. Because the distance of neighboring slices in ABUS images is fixed and small, these continuous slices were used for reconstruction as three-dimensional (3-D) US images. The 3-D tumor contour was segmented using the level-set segmentation method. Then, the 3-D features, including the texture, shape and ellipsoid fitting were extracted based on the segmented 3-D tumor contour to classify benign and malignant tumors based on the logistic regression model. The Student's t test, Mann-Whitney U test and receiver operating characteristic (ROC) curve analysis were used for statistical analysis. From the Az values of ROC curves, the shape features (0.9138) are better than the texture features (0.8603) and the ellipsoid fitting features (0.8496) for classification. The difference was significant between shape and ellipsoid fitting features (p = 0.0382). However, combination of ellipsoid fitting features and shape features can achieve a best performance with accuracy of 85.0% (125/147), sensitivity of 84.5% (60/71), specificity of 85.5% (65/76) and the area under the ROC curve Az of 0.9466. The results showed that ABUS images could be used for computer-aided feature extraction and classification of breast tumors.

Value of the correct diagnostic pathway through conventional imaging (mammography and ultrasound) in evaluating breast disease

PURPOSE

This study evaluated the role of the correct diagnostic pathway through conventional imaging in evaluating breast disease.

MATERIALS AND METHODS

Six hundred patients aged between 35 and 75 years were enrolled in the study. All patients underwent detailed history and clinical examination, ultrasound (US) and mammography. US scans were repeated after mammography. All suspicious lesions were studied by cytological and histological characterisation and magnetic resonance (MR) imaging.

RESULTS

The first US scan showed 147 solid lesions, 67 lesions characterised by posterior acoustic shadowing and 193 areas of heterogeneous echostructure. The second US scan, performed after mammography, confirmed 123/147 solid nodular lesions, 53/67 lesions characterised by posterior acoustic shadowing and 183/193 areas of heterogeneous echostructure; it also showed 13 nodular lesions not seen on the first scan and two cases of nodular lesions with irregular calcifications.

CONCLUSIONS

Our experience suggests that US not performed in conjunction with mammography gives rise to incorrect diagnostic interpretations (either false positive or false negative results). The detection rate of the US scan performed after mammography increases from 4.16% to 5.5%.