Solitary intraductal papillomas of the breast: MRI features and differentiation from small invasive ductal carcinomas

Investigation of imaging features in contrast-enhanced magnetic resonance imaging of benign and malignant breast lesions

PURPOSE

This study aimed to enhance the diagnostic accuracy of contrast-enhanced breast magnetic resonance imaging (MRI) using gadobutrol for differentiating benign breast lesions from malignant ones. Moreover, this study sought to address the limitations of current imaging techniques and criteria based on the Breast Imaging Reporting and Data System (BI-RADS).

MATERIALS AND METHODS

In a multicenter retrospective study conducted in Japan, 200 women were included, comprising 100 with benign lesions and 100 with malignant lesions, all classified under BI-RADS categories 3 and 4. The MRI protocol included 3D fast gradient echo T1- weighted images with fat suppression, with gadobutrol as the contrast agent. The analysis involved evaluating patient and lesion characteristics, including age, size, location, fibroglandular tissue, background parenchymal enhancement (BPE), signal intensity, and the findings of mass and non-mass enhancement. In this study, univariate and multivariate logistic regression analyses were performed, along with decision tree analysis, to identify significant predictors for the classification of lesions.

RESULTS

Differences in lesion characteristics were identified, which may influence malignancy risk. The multivariate logistic regression model revealed age, lesion location, shape, and signal intensity as significant predictors of malignancy. Decision tree analysis identified additional diagnostic factors, including lesion margin and BPE level. The decision tree models demonstrated high diagnostic accuracy, with the logistic regression model showing an area under the curve of 0.925 for masses and 0.829 for non-mass enhancements.

CONCLUSION

This study underscores the importance of integrating patient age, lesion location, and BPE level into the BI-RADS criteria to improve the differentiation between benign and malignant breast lesions. This approach could minimize unnecessary biopsies and enhance clinical decision-making in breast cancer diagnostics, highlighting the effectiveness of gadobutrol in breast MRI evaluations.

Unusual presentation of intraductal papilloma on the nipple: A case report

INTRODUCTION AND SIGNIFICANCE

Intraductal papilloma (IDP) is a benign breast lesion characterized by a small, delicate wart-like growth found within the milk ducts. Typically located centrally behind the nipple, IDP often presents with a serous, serosanguinous, or bloody discharge from the nipple, making it a common cause of abnormal nipple discharge. Differential diagnosis is crucial as it can be mistaken for other conditions such as pigmented Paget's disease and pigmented basal cell carcinoma.

CASE PRESENTATION

This case study depicts a 35-year-old female with a painless, pigmented mass on the nipple of her right breast that had been present for four months. Physical examination revealed a well-defined blue nodule measuring 13 × 8 mm. Although mammography and ultrasound did not detect any abnormalities in the breast tissue, a biopsy confirmed the diagnosis of intraductal papilloma. The lesion was surgically excised under local anesthesia without complications.

CLINICAL DISCUSSION

In this case, IDP presented as a blue nodule near the nipple. Despite the patient's young age and unique presentation, the diagnosis of intraductal papilloma was made based on the identified risk factors for breast tumors. Differential diagnoses considered included mammary Paget disease, nipple duct adenoma, and erosive adenomatosis of the nipple.

CONCLUSION

This case report underscores the uncommon occurrence of IDP manifesting on the nipple. A thorough evaluation incorporating medical history, physical examination, imaging studies, and cytological analysis is essential for an accurate diagnosis and to exclude malignancy. Surgical excision was successful in removing the lesion.

Comparison of Diagnostic Performance between Classic and Modified Abbreviated Breast MRI and the MRI Features Affecting Their Diagnostic Performance

Abbreviated breast magnetic resonance imaging (AB-MRI) has emerged as a supplementary screening tool, though protocols have not been standardized. The purpose of this study was to compare the diagnostic performance of modified and classic AB-MRI and determine MRI features affecting their diagnostic performance. Classic AB-MRI included one pre- and two post-contrast T1-weighted imaging (T1WI) scans, while modified AB-MRI included a delayed post-contrast axial T1WI scan and an axial T2-weighted interpolated scan obtained between the second and third post-contrast T1WI scans. Four radiologists (two specialists and two non-specialists) independently categorized the lesions. The MRI features investigated were lesion size, lesion type, and background parenchymal enhancement (BPE). The Wilcoxon rank-sum test, Fisher's exact test, and bootstrap-based test were used for statistical analysis. The average area under the curve (AUC) for modified AB-MRI was significantly greater than that for classic AB-MRI (0.76 vs. 0.70, p = 0.010) in all reader evaluations, with a similar trend in specialist evaluations (0.83 vs. 0.76, p = 0.004). Modified AB-MRI demonstrated increased AUCs and better diagnostic performance than classic AB-MRI, especially for lesion size > 10 mm (p = 0.018) and mass lesion type (p = 0.014) in specialist evaluations and lesion size > 10 mm (p = 0.003) and mild (p = 0.026) or moderate BPE (p = 0.010) in non-specialist evaluations.

False-Positive and False-Negative Contrast-enhanced Mammograms: Pitfalls and Strategies to Improve Cancer Detection

Contrast-enhanced mammography (CEM) is a relatively new breast imaging modality that uses intravenous contrast material to increase detection of breast cancer. CEM combines the structural information of conventional mammography with the functional information of tumor neovascularity. Initial studies have demonstrated that CEM and MRI perform with similar accuracies, with CEM having a slightly higher specificity (fewer false positives), although larger studies are needed. There are various reasons for false positives and false negatives at CEM. False positives at CEM can be caused by benign lesions with vascularity, including benign tumors, infection or inflammation, benign lesions in the skin, and imaging artifacts. False negatives at CEM can be attributed to incomplete or inadequate visualization of lesions, marked background parenchymal enhancement (BPE) obscuring cancer, lack of lesion contrast enhancement due to technical issues or less-vascular cancers, artifacts, and errors of lesion perception or characterization. When possible, real-time interpretation of CEM studies is ideal. If additional views are necessary, they may be obtained while contrast material is still in the breast parenchyma. Until recently, a limitation of CEM was the lack of CEM-guided biopsy capability. However, in 2020, the U.S. Food and Drug Administration cleared two devices to support CEM-guided biopsy using a stereotactic biopsy technique. The authors review various causes of false-positive and false-negative contrast-enhanced mammograms and discuss strategies to reduce these diagnostic errors to improve cancer detection while mitigating unnecessary additional imaging and procedures. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Differential Diagnosis of Benign and Malignant Breast Papillary Neoplasms on MRI With Non-mass Enhancement

RATIONALE AND OBJECTIVES

To explore the differential diagnosis of benign and malignant papillary neoplasms on MRI with non-mass enhancement.

MATERIALS AND METHODS

A total of 48 patients with surgically confirmed papillary neoplasms showing non-mass enhancement were included. Clinical findings, mammography and MRI features were retrospectively analyzed, and lesions were described according to the breast imaging report and data system (BI-RADS). Multivariate analysis of variance was used to compare the clinical and imaging features of benign and malignant lesions.

RESULTS

Fifty-three papillary neoplasms were shown on MR images with non-mass enhancement, including 33 intraductal papilloma and 20 papillary carcinomas (9 intraductal papillary carcinoma, 6 solid papillary carcinomas, and 5 invasive papillary carcinoma). Mammography showed amorphous calcification in 20% (6/30), of which 4 were in papilloma and 2 were in papillary carcinoma. On MRI, papilloma mostly showed linear distribution in 54.55% (18/33), clumped enhancement in 36.36% (12/33). Papillary carcinoma showed segmental distribution in 50% (10/20), clustered ring enhancement in 75% (15/20). ANOVA showed age (p = 0.025), clinical symptoms (p < 0.001), apparent diffusion coefficient (ADC) value (p = 0.026), distribution pattern (p = 0.029) and internal enhancement pattern (p < 0.001) were statistically significant between benign and malignant of papillary neoplasms. Multivariate analysis of variance suggested that the internal enhancement pattern was the only statistically significant factor (p = 0.010).

CONCLUSIONS

Papillary carcinoma on MRI with non-mass enhancement mostly showed internal clustered ring enhancement, while papilloma mostly showed internal clumped enhancement; additional mammography is of limited diagnostic value, and suspected calcification occurs mostly in papilloma.

Mammographic and Sonographic Findings of Intraductal Papilloma of the Right Breast: A Case Report

Intraductal papillomas are tumors that arise in the epithelial cells of the mammary duct. Common presenting symptoms for intraductal papilloma include serous or serosanguinous nipple discharge or a palpable mass. We present a case of a 48-year-old woman who presented with spontaneous right breast nipple discharge and a palpable mass. Diagnostic imaging for the patient included mammography and ultrasound with color doppler imaging that revealed a mass at eight o'clock in the right breast at a distance of 2 cm from the nipple and that corresponded to the area of palpable concern. Percutaneous ultrasound-guided biopsy of the mass confirmed a diagnosis of intraductal papilloma. Surgical excision may be required in many cases of an intraductal papilloma due to the variety of diagnoses that can be included on the differential, the increased risk for cellular atypia, and the treatment for spontaneous nipple discharge.

Management of Intraductal Papilloma of the Breast Diagnosed on Core Needle Biopsy: Latest Controversies

Intraductal papillomas (IDPs), including central papilloma and peripheral papilloma, are common in the female population. Due to the lack of specific clinical manifestations of IDPs, it is easy to misdiagnose or miss diagnose. The difficulty of differential diagnosis using imaging techniques also contributes to these conditions. Histopathology is the gold standard for the diagnosis of IDPs while the possibility of under sample exists in the percutaneous biopsy. There have been some debates about how to treat asymptomatic IDPs without atypia diagnosed on core needle biopsy (CNB), especially when the upgrade rate to carcinoma is considered. This article concludes that further surgery is recommended for IDPs without atypia diagnosed on CNB who have high-risk factors, while appropriate imaging follow-up may be suitable for those without risk factors.

Contribution of Diffusion-Weighted Imaging and ADC Values to Papillary Breast Lesions

This study aimed to evaluate the role of apparent diffusion coefficient (ADC) values obtained from diffusion-weighted imaging (DWI) in the differentiation of malignant from benign papillary breast lesions. The magnetic resonance imaging (MRI) data of 94 breast papillary lesions confirmed by pathology were retrospectively analyzed. The differences in ADC values of papillary lesions under different enhancements in MRI and different pathological types were investigated, and the ADC threshold was determined by the receiver operating characteristic curve for its potential diagnostic value. The mean ADC values in borderline and malignant lesions (1.01 ± 0.20 × 10-3 mm2/s) were significantly lower compared to benign lesions (1.21 ± 0.27 × 10-3 mm2/s) (P &lt; 0.05). The optimal threshold of the ADC value could be 1.00 × 10-3 mm2/s. The ADC values were statistically significant in differentiating between benign and malignant papillary lesions whether in mass or non-mass enhancement (P &lt; 0.05). However, there were no statistical differences in the ADC values among borderline or any other histological subtypes of malignant lesions (P &gt; 0.05). Measuring ADC values from DWI can be used to identify benign and malignant breast papillary lesions. The diagnostic performance of the ADC value in identifying benign and malignant breast lesions is not affected by the way of lesion enhancement. However, it shows no use for differential diagnosis among malignant lesion subtypes for now. The ADC value of 1.00 × 10-3 mm2/s can be used as the most appropriate threshold for distinguishing between benign and malignant breast papillary lesions.

Papillary Lesions of the Breast: Addition of DWI and TIRM Sequences to Routine Breast MRI Could Help in Differentiation Benign from Malignant

AIM

We aimed to investigate the magnetic resonance imaging (MRI) features of benign, atypical or malignant papillary breast lesions and to assess additional value of diffusion-weighted imaging (DWI) and turbo inversion recovery magnitude (TIRM) sequences to routine breast MRI.

BACKGROUND

Differentiation between benign and malignant papillary breast lesions is essential for patient management. However, morphologic features and enhancement patterns of malignant papillary lesions may overlap with those of benign papilloma.

METHODS

Seventy two papillary breast lesions (50 benign, 22 atypical or malignant) were included in the current study, retrospectively. We divided the patients into two groups as benign papillary breast lesions and atypical or malignant papillary breast lesions. Morphologic, dynamic, turbo inversion recovery magnitude (TIRM) values and diffusion features of the papillary lesions were compared between two groups.

RESULTS

Benign papillary lesions were smaller in size (p=0.006 and p=0.005, for radiologist 1 and 2 respectively), closer to areola (p=0.045 and 0.049 for radiologist 1 and 2 respectively) and had higher ADC values (p=0.001 for two radiologists) than atypical or malignant group. ROC curves showed diagnostic accuracy for ADC (AUC=0.770 and 0.762, p<0.0001 for two radiologists) and showed a cut-off value of ≤957 x 10-6 mm2/s (radiologist 1) and ≤ 910 x 10-6 mm2/s (radiologist 2).

CONCLUSION

MRI is a useful method for differentiation between benign and malignant papillary breast lesions. Centrally located, lesser in size and higher ADC values should be considered benign, whereas peripherally located, larger in size and lower ADC values should be considered malignant.

Diagnostic performance of mammography and magnetic resonance imaging for evaluating mammographically visible breast masses

OBJECTIVE

We compared the diagnostic values of mammography and magnetic resonance imaging (MRI) for evaluating breast masses.

METHODS

We retrospectively analyzed mammography, MRI, and histopathological data for 377 patients with breast masses on mammography, including 73 benign and 304 malignant masses.

RESULTS

The sensitivities and negative predictive values (NPVs) were significantly higher for MRI compared with mammography for detecting breast cancer (98.4% vs. 89.8% and 87.8% vs. 46.6%, respectively). The specificity and positive predictive values (PPV) were similar for both techniques. Compared with mammography alone, mammography plus MRI improved the specificity (67.1% vs. 37.0%) and PPV (91.8% vs. 85.6%), but there was no significant difference in sensitivity or NPV. Compared with MRI alone, the combination significantly improved the specificity (67.1% vs. 49.3%), but the sensitivity (88.5% vs. 98.4%) and NPV (58.3% vs. 87.8%) were reduced, and the PPV was similar in both groups. There was no significant difference between mammography and MRI in terms of sensitivity or specificity among 81 patients with breast masses with calcification.

CONCLUSION

Breast MRI improved the sensitivity and NPV for breast cancer detection. Combining MRI and mammography improved the specificity and PPV, but MRI offered no advantage in patients with breast masses with calcification.

Contrast mammography in clinical practice: Current uses and potential diagnostic dilemmas

OBJECTIVE

This article will discuss the indications for Contrast Enhanced Spectral Mammography (CESM) with a focus on imaging interpretation including diagnostic dilemmas and pitfalls which may be encountered in practice.

CONCLUSION

Understanding potential diagnostic dilemmas and pitfalls of CESM allows for enhanced interpretation. The clinical utilization of Contrast Enhanced Spectral Mammography (CESM) has increased significantly over the last few years. CESM demonstrates comparable sensitivity and accuracy to magnetic resonance imaging (MRI) for the evaluation of breast cancer but is less time consuming and less expensive. Because of this, CESM is now being used in lieu of MRI for many diagnostic indicators including the evaluation of abnormal mammographic findings, extent of disease, and response to neoadjuvant therapy. Additionally, ongoing research into the role of CESM in asymptomatic screening for breast cancer is evolving. As this technique becomes more popular, focusing on appropriate technique and interpretation is important. This article reviews the current and potential roles of CESM. It provides examples of CESM utilized for diagnostic indications while highlighting diagnostic dilemmas, pitfalls, and artifacts that may be encountered when interpreting CESM images.

A retrospective observational study of intraductal breast papilloma and its coexisting lesions: A real-world experience

Background

Breast intraductal papilloma is a heterogeneous group. The aim of the study is to investigate the intraductal breast papilloma and its coexisting lesions retrospectively in real‐world practice.

Methods

We retrospectively identified 4450 intraductal breast papilloma and its coexisting lesions.

Results

About 18.36% of intraductal papilloma coexisted with malignant lesions of the breast, 37.33% coexisted with atypia hyperplasia (AH), 25.24% coexisted with benign lesions, and only 19.10% coexisted without concomitant lesions. In addition, 36.80% of intraductal breast papilloma had nipple discharge, 51.46% had a palpable breast mass, and 16.45% had both nipple discharge and a palpable breast mass. About 28.18% experienced discomfort or were asymptomatic. Furthermore, 98.99% had ultrasound abnormalities, and 53.06% had intraductal hypoechogenicity upon ultrasound. 31.89% had mammographic distortion, and 14.45% had microcalcification upon mammography. Intraductal breast papilloma with malignancy had significant correlations with clinical manifestations.

Conclusion

Coexisting malignancy was also related to ultrasound abnormality (BIRADS 4C and 5), mammographic distortion, and microcalcification upon mammography but was not related to the intraductal hypoechoic upon ultrasound. Coexisting atypical hyperplasia correlated with nipple discharge but not palpable mass, mammographic distortion, or intraductal hypoechoic upon ultrasound. The coexisting AH was also related to abnormality upon ultrasound or microcalcification compared with the benign lesions. The intraductal papilloma coexists with malignancy or AH accounted for more than 50%, and the clinical information on papilloma and its coexisting lesions is nonspecific. We recommended surgical treatment for benign intraductal papillary lesions.

Risk factors of breast intraductal lesions in patients without pathological nipple discharge

The majority of breast cancer arises from the ductal epithelium. It is crucial in the diagnosis and treatment of breast cancer by detecting intraductal lesions at an early stage. The typical clinical characteristic of intraductal lesions is pathological nipple discharge (PND), although many patients with intraductal lesions do not exhibit PND. It is a serious challenge for clinicians to detect patients with intraductal lesions without PND at an early stage. The aim of the present study was to investigate the risk factors associated with intraductal lesions in patients without PND. This retrospective database review, conducted between April 2016 and April 2017, included 370 lesions from 255 patients with intraductal lesions (intraductal papilloma, atypical intraductal hyperplasia, intraductal carcinoma in situ) and non-intraductal lesions (fibroadenoma, adenosis, cysts, lobular carcinoma in situ), diagnosed through surgical pathology. The patients were divided into two groups based on pathological diagnosis and clinical parameters were evaluated using univariate and multivariate analyses. Univariate analysis revealed that 9 of 14 factors were statistically significant. Five factors were identified to be associated risk factors in patients without PND through the multivariate logistic regression analysis: Age between 35 and 49 years and age ≥50 years [odds ratio (OR)=4.749, 95% confidence interval (CI)=2.371-9.513, P<0.001; OR=2.587, 95% CI=2.587-14.891, P<0.001; respectively], non-menstrual breast pain (OR=1.922, 95% CI=1.037-3.564, P=0.038), breast duct dilatation as seen using ultrasonography (OR=9.455, 95% CI=3.194-27.987, P<0.001), lesion distance from nipple ≤2 cm (OR=2.747, 95% CI=1.668-4.526, P<0.001) and lesion size ≤1 cm (OR=1.903, 95% CI=1.155-3.136, P=0.012). In conclusion, for patients without PND but with risk factors, such as the patient being >35 years, with non-menstrual breast pain, breast duct ectasia, lesion distance from nipple ≤2 cm and lesion size ≤1 cm as seen using ultrasonography, clinicians should be highly concerned about the possibility of intraductal lesions, in order to prevent misdiagnosis and reduce the misdiagnosis rate.

The role of magnetic resonance imaging in detection and surgical treatment of breast intraductal papillomas

Background

Intraductal papillomas are discrete benign tumors of the breast duct epithelium. Due to the risk of subsequent carcinoma, a surgical excision is generally recommended as a precaution. However, it is difficult to initially diagnose and accurately locate the lesions both in pre-surgery and surgery periods.

Methods

Retrospectively analyzed 245 patients, with a pathologically proven breast intraductal papillomas. All the patients underwent magnetic resonance imaging (MRI) scans and ultrasound examination(s) pre-surgery and/or in surgery. All the patients who underwent surgery were divided into four groups according to the following operation method type(s): ultrasound & clinical examination excision, methylene blue notation excision, methylene blue notation & MRI guide excision, and MRI guide excision. Then, the differences between the last two MRI guide excisions and the first two conventional methods were analyzed. Afterwards, 238 patients were followed up for recurrence checks. SPSS 19.0 statistical software was used and the results of P<0.05 being considered statistically significant.

Results

A total of 161 (65.7%) and 48 (19.6%) patients were pathological diagnosed of solitary and multiple papilloma separately, and 36 (14.7%) patients had papillomatosis; 168 and 243 cases with positive signs, which were detected in all 245 patients who had underwent ultrasound and MRI examination(s), with the detection rate being 68.6% and 99.0% respectively. MRI imaging could clearly present mass-like lesions (solitary and multiple mass) and non-mass like lesions (ductal and regional). Whereas, ultrasound imaging could barely show mass-like (solitary and multiple mass) lesions. In surgery, when compared with traditional methods, MRI imaging could also more accurately locate the lesions and guide the excision. MRI guidance is both applicable to patients with and without nipple discharge, in addition to those who show no abnormal signs in ultrasound imaging. The recurrence-free survival time with traditional surgery methods was significantly lower than those in the MRI guide groups.

Conclusions

MRI is accurate at the detection, localization and resection range of intraductal papilloma lesions; all capabilities which are critical to successful breast surgery.

Magnetic resonance imaging features for differentiating breast papilloma with high-risk or malignant lesions from benign papilloma: a retrospective study on 158 patients

Background

Benign breast papilloma is currently managed with conservative management with close observation. In contrast, papilloma with high-risk or malignant lesions warrants surgical excision. The purpose of our study was to investigate magnetic resonance imaging (MRI) features of breast papilloma and to identify imaging diagnostic indicators for papilloma with high-risk or malignant lesions.

Methods

MRI features of 175 surgically confirmed papillomas on 158 patients were retrospectively reviewed. The 175 cases included 132 cases of benign papilloma and 43 cases of papilloma with high-risk or malignant lesions. The MRI features of these lesions were classified into three types: mass, non-mass enhancement (NME), and occult lesion. The occult lesion was defined as the presence of only ductal dilation without any enhanced lesions on MRI. For a mass lesion, the mixed mass-NME lesion was considered if linear, segmental or regional enhanced lesion was found adjacent to the mass. Clinical and MRI features were compared by univariate and multivariate analysis between the benign papilloma and the papilloma with high-risk or malignant lesions.

Results

Multivariate logistic regression analysis demonstrated that clinical characteristics including being or older than 50 years (odds ratio [OR] = 4.506), having bloody nipple discharge (OR = 4.499), and concurrent breast cancer (OR = 5.083) were significant indicators for papilloma with high-risk or malignant lesions. On MRI, most papillomas presented as mass (n = 135, 77.1%), and fewer as NME (n = 37, 21.1%) and occult lesion (n = 3, 1.7%). For the mass lesion, the logistic regression analysis demonstrated that a mass size exceeding 10 mm (OR = 2.956) and mixed mass-NME lesion (OR = 4.143) were independent risk indicators for a papilloma with high-risk or malignant lesions. For the NME lesion, the segmental or regional distribution was more commonly observed in the papilloma with high-risk or malignant lesions (61.5%) than the benign papilloma (12.5%) (P = 0.006). All the cases of occult lesions were benign papillomas.

Conclusions

MRI features including a mass size exceeding 10 mm, mixed mass-NME lesion, and NMEs with segmental or regional distribution indicate a papilloma with high-risk or malignant lesions.

A case of giant complicated intraductal papilloma of breast on MRI and literature review

BACKGROUND

With the increasing use of image-guided biopsy, more breast intraductal papillomas are found than ever. Most intraductal papillomas are small, ranging from several milimeters to 2 cm.

CASE

We described a case of giant intraductal papilloma of breast in a 19-year-old girl with nipple bloody discharge and rapid growth. Magnetic resonance imaging diagnostic evaluation and pathologic correlation along with review of relevant literatures are documented. The lesion was characterized by presence of mixture of cystic and solid component with cystic component occupying a large space. The solid component showed morphologic, kinetic, and diffusion weighted imaging features suggestive of malignancy. Infarction with no enhancement was noted. Cystic compartments contained hemorrhage with fluid-fluid level formation. The patient undertook lumpectomy.

CONCLUSION

For a giant breast tumor with mixed solid and cystic component, intraductal papilloma should be considered in the differential diagnosis.

T2-hypointense rim of breast mass lesions on magnetic resonance images: Radiologic-pathologic correlation

We investigated the radiologic-pathologic correlation of a strong hypointense rim on T2-weighted images (T2-hypo-rim) surrounding breast mass lesions and evaluated its clinical significance. We retrospectively reviewed 3503 consecutive breast magnetic resonance imaging (MRI) examinations. The T2-hypo-rim was defined as a border of strong hypointensity compared with the fat signal on fat-suppressed T2-weighted images. Detected lesions with T2-hypo-rim were classified as a solid or cystic mass with MRI and correlated with histopathologic findings. Sixty-two masses (2%; 34 solid, 28 cystic) with T2-hypo-rim were detected [44 breast cancers, 18 benign lesions, including 15 (24%) papillary tumors]. Patients with cancer were significantly older than those with benign lesions (P = .002). Breast cancers were significantly larger than benign masses (P = .023). In 49 of 62 lesions (24 solid and 16 cystic cancers; three solid and six cystic benign masses), the rims were accurately correlated with the histopathologic findings. All malignant and benign cystic masses exhibited hemosiderin deposits in the cyst walls. However, 22 of 24 solid cancers and no solid benign masses exhibited hemosiderin at the tumor periphery (92% and 0%, respectively, P < .001). In addition, a thick fibrous capsule was present in nine (38%) of 24 solid cancers and none of the solid benign lesions. Strong T2-hypo-rims mostly correlated with hemosiderin deposits and/or sometimes fibrous capsules. Although the rims could not distinguish malignant from benign cystic lesions, they indicated malignancy in solid mass lesions on MRI. Additionally, the rims often indicated papillary tumors.

The Value of Lesion Size as an Adjunct to the BI-RADS-MRI 2013 Descriptors in the Diagnosis of Solitary Breast Masses

Purpose:

This study aimed to evaluate the MRI findings of breast solitary masses in diagnostic procedures to decide the appropriate category based on American College of Radiology (ACR) BI-RADS-MRI 2013, with the focus on lesion size.

Methods:

A retrospective review of 2,603 consecutive breast MRI reports identified 250 pathologically-proven solitary breast masses. Dynamic-contrast enhanced images and diffusion-weighted images were performed on a 3.0/1.5 Tesla Scanner with a 16/4 channel dedicated breast coil. MRI findings were re-evaluated according to ACR BI-RADS-MRI 2013. BI-RADS-MRI descriptors, lesion size and minimum apparent diffusion coefficient (ADC) value were statistically analyzed using univariate/multivariate logistic regression analysis and receiver operator characteristic (ROC) analysis. Based on the results, a diagnostic decision tree was constructed.

Results:

Of the 250 lesions, 152 (61%) were malignant and 98 (39%) were benign. In univariate logistic regression analysis, most of the BI-RADS descriptors, lesion size, and ADC value were significant. Lesion size and ADC value were binarized with optimal cut-off values of 12 mm and 1.1 × 10⁻³ mm²/s, respectively. Multivariate logistic regression analysis showed that lesion size (≥12 mm or not), margin (circumscribed or not), kinetics (washout or not) and internal enhancement characteristics (IEC) (rim enhancement present or absent) significantly contributed to the diagnosis (P < 0.05). Using these four significant parameters, a decision tree was constructed to categorize lesions into detailed assessment categories/subcategories (Category 4A, 4B, 4C and 5).

Conclusion:

Lesion size is an independent contributor in diagnosing solitary breast masses. Adding the information of lesion size to BI-RADS-MRI 2013 descriptors will allow more detailed categorizations.

Diagnostic evaluations of ultrasound and magnetic resonance imaging in mammary duct ectasia and breast cancer

The objective of the present study was to evaluate the diagnostic efficiency of ultrasound (US) and magnetic resonance imaging (MRI) in the diagnosis and differential diagnosis of mammary duct ectasia (MDE) and breast cancer. This retrospective study was performed on 35 patients with MDE and 105 patients with breast cancer using US and MRI. Imaging features, semi-quantitative and quantitative parameters were analyzed to determine their diagnostic value for MDE and breast cancer. The average age of patients with breast cancer was increased compared with that of patients with MDE. There were no significant differences in local packages with or without tenderness ratio (P=0.259) and grade of color Doppler flow imaging (P=0.273) between the two groups. However, the morphological changes were significantly increased in breast cancer compared with MDE. In addition, there were significant diagnostic differences in US and MRI between breast cancer and MDE, including resistance index, US elastography, time-signal intensity curve, apparent diffusion coefficient, early-stage enhancement ratio, peak-of-enhancement ratio and T_peak (P<0.05). However, there were no observable significant diagnostic differences between US, MRI and US with MRI for MDE and breast cancer (P=0.103, P=0.263 and P=0.403 respectively). Diagnosis of MDE and breast cancer requires full evaluation of multiple parameters and morphological changes of US and MRI to increase the diagnostic efficiency. US, MRI and US with MRI were all of diagnostic value for MDE and breast cancer, while US with MRI had the highest efficacy.

Can unenhanced breast MRI be used to decrease negative biopsy rates?

PURPOSE

We aimed to determine whether low-risk breast masses can be effectively managed with unenhanced magnetic resonance imaging (MRI) combining T2-weighted sequences with diffusion-weighted imaging (DWI) instead of immediate biopsy to decrease negative biopsy rates.

METHODS

After institutional review board and patient approvals, 141 consecutive women with 156 low-risk breast masses, who underwent unenhanced MRI and later on received a final diagnosis, were included in the study. There were 72 BI-RADS 3 masses in women with relative risk factors and 84 BI-RADS 4A masses, all referred for biopsy. Apparent diffusion coefficient (ADC) cutoff was 0.90×10-3 mm2/s. According to ADC values and T2-weighted imaging characteristics, masses were classified as either malignant or benign. Unenhanced MRI results were compared with final diagnoses obtained by histopathology or imaging surveillance, and diagnostic values were calculated.

RESULTS

Of 156 masses, 112 underwent biopsy. Four malignancies were diagnosed, three of which having ADC values lower than the cutoff. In women who rejected the biopsy, masses were stable during a follow-up of at least two years (n=44). MRI revealed 91% specificity and 99% negative predictive value (NPV) for detection of breast cancer.

CONCLUSION

Combination of T2-weighted imaging with DWI is a feasible method to further characterize breast masses with a low probability of malignancy. With the use of unenhanced MRI instead of immediate biopsy, it might be possible to decrease negative biopsy rates of low-risk breast masses.

Incidentally detected enhancing lesions found in breast MRI: analysis of apparent diffusion coefficient and T2 signal intensity significantly improves specificity

OBJECTIVES

To evaluate the value of adding T2- and diffusion-weighted imaging (DWI) to the BI-RADS® classification in MRI-detected lesions.

METHODS

This retrospective study included 112 consecutive patients who underwent 3.0T structural breast MRI with T2- and DWI on the basis of EUSOMA recommendations. Morphological and kinetic features, T2 signal intensity (T2 SI) and apparent diffusion coefficient (ADC) findings were assessed.

RESULTS

Thirty-three (29.5 %) patients (mean age 57.0 ± 12.7 years) had 36 primarily MRI-detected incidental lesions of which 16 (44.4 %) proved to be malignant. No single morphological or kinetic feature was associated with malignancy. Both low T2 SI (P = 0.009) and low ADC values (≤0.87 × 10^-3 mm²s^-1, P < 0.001) yielded high specificity (80.0 %/80.0 %). The BI-RADS classification supplemented with information from DWI and T2-WI improved the diagnostic performance of the BI-RADS classification as sensitivity remained 100 % and specificity improved from 30 % to 65.0 %. The numbers of false positive lesions declined from 39 % (N = 14) to 19 % (N = 7).

CONCLUSION

MRI-detected incidental lesions may be challenging to characterize as they have few specific malignancy indicating features. The specificity of MRI can be improved by incorporating T2 SI and ADC values into the BI-RADS assessment.

KEY POINTS

• MRI-detected incidental lesions have few specific malignancy indicating features. • ≥ 1 suspicious morphologic or kinetic feature may warrant biopsy. • T2 signal intensity and DWI assessment are feasible in primarily MRI-detected lesions. • T2 SI and DWI assessment improve the BI-RADS specificity in MRI-detected lesions.

MRI characteristics of intraductal papilloma

BACKGROUND

Intraductal papilloma (IDP) is the most common pathological finding in women with pathological nipple discharge. Magnetic resonance imaging (MRI) has shown potential for characterizing breast tumors; however, MRI findings of IDPs are inconclusive, and certain diagnostic standards are lacking.

PURPOSE

To characterize the MRI features of IDP from a relatively large cohort.

MATERIAL AND METHODS

We retrospectively reviewed from 358 women with IDPs that were confirmed by histopathology. The clinical and imaging findings in 70 patients who underwent preoperative MRI were analyzed. MRI analyses included morphology and dynamic contrast-enhanced MRI.

RESULTS

In 70 patients, 77 IDPs were detected on MRI, which revealed the following three patterns: small luminal mass papillomas; tumor-like papillomas; and MRI-occult papillomas. Fourteen IDPs involved small, oval, smooth, and contrast-enhanced masses at the posterior end of the enlarged duct corresponding to small luminal mass papillomas. Seven IDPs had large diameters along the direction of the breast duct, indicating the typical MRI findings for IDP. Of 47 tumor-like papillomas, 16 cases showed large diameters along the direction of the breast duct and close to the nipple (within 4 cm), seven cases resembled invasive breast cancer on MRI, and the remaining 24 were (24/47) undistinguishable from other benign breast diseases. Sixteen IDPs were MRI-occult papillomas that could not be distinguished from the surrounding benign disease by either contrast-enhanced MRI or fat-suppressed T2-weighted MRI.

CONCLUSION

Small luminal mass papillomas or tumor-like papillomas with the largest diameters along the direction of the breast duct and close to the nipple (within 4 cm) might be the typical MRI findings for IDPs.

Completely removing solitary intraductal papillomas using the Mammotome system guided by ultrasonography is feasible and safe

BACKGROUND

Because of the potential for an intraductal papilloma to progress to malignancy and the likelihood of detecting unexpected coexisting malignant disease, complete removal of the intraductal papilloma is safer than merely sampling it. The purpose of this study was to estimate the feasibility and safety of excising a solitary intraductal papilloma using the Mammotome system guided by ultrasonography (US).

METHODS

We retrospectively reviewed the clinical information of 136 patients who underwent excision of solitary intraductal papillomas using the 8-gauge probe with the US-guided Mammotome system between December 2005 and December 2011 at our institution. Their lesions had been suspected preoperatively or were occasionally diagnosed postoperatively.

RESULTS

There were no local recurrences during the follow-up period. Of the patients who showed atypia and underwent re-excision, only 2 (6.1 %) had local ductal atypia. The patients with atypia were significantly older than the patients without atypia (p < 0.05).

CONCLUSIONS

Using the US-guided 8-gauge probe Mammotome system to completely remove a solitary intraductal papilloma is feasible and safe. Close follow-up may be considered for those whose lesions exhibit atypia.

Radiologic-pathologic correlation at breast MR imaging: what is the appropriate management for high-risk lesions?

Breast magnetic resonance (MR) imaging is increasingly performed for a variety of indications, most commonly with the goal of detecting breast cancer. Percutaneous biopsy (usually under MR guidance or ultrasound if there is a correlating finding) is commonly used to evaluate suspicious imaging findings detected on MR imaging with the goal of identifying malignancy. It is important to be familiar with the characteristics and management of high-risk lesions detected or biopsied under MR guidance. This review focuses on the appearance of a variety of breast lesions detected on MR imaging that require excision with focus on pathologic correlation.