Role of breast magnetic resonance imaging in predicting malignant invasion of the nipple-areolar complex: Potential predictors and reliability between inter-observers

Diagnostic Accuracy of Magnetic Resonance Imaging Features and Tumor-to-Nipple Distance for the Nipple-Areolar Complex Involvement of Breast Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis evaluated the accuracy of preoperative breast magnetic resonance imaging (MRI) features and tumor-to-nipple distance (TND) for diagnosing occult nipple-areolar complex (NAC) involvement in breast cancer.

MATERIALS AND METHODS

The MEDLINE, Embase, and Cochrane databases were searched for articles published until March 20, 2022, excluding studies of patients with clinically evident NAC involvement or those treated with neoadjuvant chemotherapy. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Two reviewers independently evaluated studies that reported the diagnostic performance of MRI imaging features such as continuity to the NAC, unilateral NAC enhancement, non-mass enhancement (NME) type, mass size (> 20 mm), and TND. Summary estimates of the sensitivity and specificity curves and the summary receiver operating characteristic (SROC) curve of the MRI features for NAC involvement were calculated using random-effects models. We also calculated the TND cutoffs required to achieve predetermined specificity values.

RESULTS

Fifteen studies (n = 4002 breast lesions) were analyzed. The pooled sensitivity and specificity (with 95% confidence intervals) for NAC involvement diagnosis were 71% (58-81) and 94% (91-96), respectively, for continuity to the NAC; 58% (45-70) and 97% (95-99), respectively, for unilateral NAC enhancement; 55% (46-64) and 83% (75-88), respectively, for NME type; and 88% (68-96) and 58% (40-75), respectively, for mass size (> 20 mm). TND had an area under the SROC curve of 0.799 for NAC involvement. A TND of 11.5 mm achieved a predetermined specificity of 85% with a sensitivity of 64%, and a TND of 12.3 mm yielded a predetermined specificity of 83% with a sensitivity of 65%.

CONCLUSION

Continuity to the NAC and unilateral NAC enhancement may help predict occult NAC involvement in breast cancer. To achieve the desired diagnostic performance with TND, a suitable cutoff value should be considered.

Nipple-sparing Mastectomy: What the Radiologist Should Know

Nipple-sparing mastectomy (NSM) is increasingly offered to patients undergoing treatment of breast cancer and prophylaxis treatment for reduction of breast cancer risk. NSM is considered oncologically safe for appropriately selected patients and is associated with improved cosmetic outcomes and quality of life. Accepted indications for NSM have expanded in recent years, and currently only inflammatory breast cancer or malignancy involving the nipple is considered an absolute contraindication. Neoplasms close to and involving the nipple areolar complex are common, and cancer of the lactiferous ducts can spread to the nipple. Therefore, accurate determination of nipple involvement at imaging examinations is critical to identifying appropriate candidates for NSM and preventing local recurrence. Multiple imaging features have been described as predictors of nipple involvement, with tumor to nipple distance, enhancement between the index malignancy and the nipple, and nipple retraction demonstrating the highest predictive values. These features can be assessed at multimodality breast imaging, particularly at breast MRI, which demonstrates high specificity and negative predictive value for determining nipple involvement in malignancy. Online supplemental material is available for this article. ^©RSNA, 2022.

Prediction of nipple-areolar complex involvement by breast cancer: role of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)

Background

Skin-sparing and nipple-sparing mastectomies were considered as alternative techniques for modified radical mastectomy. In patients who are candidates for nipple-sparing mastectomy, preoperative assessment of the nipple-areolar complex (NAC) is essential for adequate surgical planning. Breast MRI is highly sensitive for cancer detection and has an important role in disease staging. The aim of this study was to estimate the role of DCE-MRI in predicting malignant NAC invasion by underlying breast cancer and assess the best predictors on MRI that can suspect malignant NAC invasion.

Results

Out of the 125 patients with breast cancer, 33 patients (26.4%) showed malignant NAC invasion. On basis of multivariate analysis, abnormal nipple enhancement, tumor nipple enhancement, tumor nipple distance ≤ 2 cm, and abnormal and asymmetric nipple morphology were all significant predictors of malignant NAC invasion (P < 0.001) with abnormal unilateral nipple enhancement as the most important independent MRI predictor of malignant NAC invasion (odds ratio = 61.07, 95% CI 12.81–291.22, P < 0.001). When combining more than positive suspicious MRI features, DCE-MRI had 66.6% sensitivity, 76% specificity, 50% PPV, 86.4% NPV, and 73.6% accuracy in prediction of malignant NAC invasion.

Conclusion

DCE-MRI could predict malignant NAC invasion with abnormal unilateral nipple enhancement as the most important independent MRI predictor.

Magnetic resonance imaging in the evaluation of pathologic nipple discharge: indications and imaging findings

Pathologic nipple discharge (PND) is typically unilateral, spontaneous, involves a single duct, and is serous or bloody in appearance. In patients with PND, breast MRI can be helpful as an additional diagnostic tool when conventional imaging with mammogram and ultrasound are negative. MRI is able to detect the etiology of nipple discharge in 56-61% of cases when initial imaging with mammogram and ultrasound are negative. Advantages to using MRI in evaluation of PND include good visualization of the retroareolar breast and better evaluation of posterior lesions which may not be well evaluated on mammograms and galactograms. It is also less invasive compared to central duct excision. Papillomas and nipple adenomas are benign breast masses that can cause PND and are well visualized on MRI. Ductal ectasia, and infectious etiologies such as mastitis, abscess, and fistulas are additional benign causes of PND that are well evaluated with MRI. MRI is also excellent for evaluation of malignant causes of PND including Paget's disease, ductal carcinoma in-situ and invasive carcinoma. MRI's high negative predictive value of 87-98.2% is helpful in excluding malignant etiologies of PND.

A novel MRI-based predictive index can identify patients suitable for preservation of the nipple-areola complex in breast reconstructive surgery

INTRODUCTION

Accurately predicting nipple-areola complex (NAC) involvement in breast cancer is necessary for identifying patients who may be candidates for a nipple-sparing mastectomy. Although multiple risk factors are indicated in the guidelines, it is difficult to predict NAC involvement (NAC-i) preoperatively even if these factors are evaluated individually. This study aimed to develop a more accurate and practical preoperative NAC-i prediction model using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

All tumors in 252 patients were evaluated using postcontrast T1-weighted subtraction on MRI.

RESULTS

The receiver operating characteristic curves identified cut-off values for tumor size and tumor-to-nipple distance (TND) as 4 cm and 1.2 cm, respectively. Multivariate analysis demonstrated that TND (p < 0.001), ductal enhancement extending to the nipple (DEEN) (p < 0.001), and nipple enhancement (NE) (p = 0.005) were independent clinical risk factors for pathological NAC-i. A formula was constructed using odds ratios for these three independent preoperative risk factors in multivariate analysis: the MRI-based NAC-i predictive index (mNACPI) = TND × 4 + DEEN × 3 + NE × 1. A total score of ≤4 points was defined as low risk and ≥5 points as high risk. NAC-i rates were 2.4% in the low-risk group and 89.4% in the high-risk group; a significant correlation was observed between the risk group and permanent pathological NAC-i (p < 0.001). Assuming that the NAC was preserved in low-risk patients and resected in high-risk patients, NAC-i was verified using the mNACPI.

CONCLUSION

mNACPI may contribute greatly to the improvement of selecting suitable patients for NAC preservation in breast reconstructive surgery while maintaining oncological safety.

Multimodality approach to the nipple-areolar complex: a pictorial review and diagnostic algorithm

The anatomic and histologic characteristics of the nipple-areolar complex make this breast region special. The nipple-areolar complex can be affected by abnormal development and a wide spectrum of pathological conditions, many of which have unspecific clinical and radiological presentations that can present a challenge for radiologists. The nipple-areolar complex requires a specific imaging workup in which a multimodal approach is essential. Radiologists need to know the different imaging modalities used to study the nipple-areolar complex, as well as their advantages and limitations. It is essential to get acquainted with the acquisition technique for each modality and the spectrum of findings for the different conditions. This review describes and illustrates a combined clinical and radiological approach to evaluate the nipple-areolar complex, emphasizing the findings for the normal morphology, developmental abnormalities, and the most common benign and malignant diseases that can affect this region. We also present a diagnostic algorithm that enables a rapid, practical approach to diagnosing condition involving the nipple-areolar complex.

Clinical and sonographic features of nipple lesions

BACKGROUND

The aim of this study was to present several cases of benign and malignant nipple lesions and contribute to diagnosis and differential diagnosis.

METHODS

A retrospective study was conducted on 13 patients. All of the patients were evaluated by ultrasonography, and 11 of them had pathological results. We analyzed the clinical and sonographic features.

RESULTS

There were 3 malignant lesions, 7 benign lesions, and 3 congenital nipple dysplasia, listed as follows:Malignant lesions (n = 3, 23%): Paget's disease (PD, n = 3, 23%). All of the patients with PD showed unilateral nipple erosion, discharge, and pain. The ultrasound showed abundant blood flow (n = 3, 23%); 2 patients (n = 2, 15%) had microcalcifications.Benign lesions (n = 7, 54%): Adenoma of the nipple (n = 2, 15%). One patient (n = 1, 8%) had nipple erosion and discharge. Two patients (n = 2, 15%) had a palpable nodule in the nipple. The ultrasound of both patients (n = 2, 15%) showed regular-shaped, clear border nodule with abundant blood flow (n = 2, 15%).Leiomyoma of the nipple (n = 1, 8%): This male patient was characterized by unilateral nipple enlargement and pain. The ultrasound showed a regular nodule with absent blood flow.Plasma cell mastitis (n = 2, 15%): Two patients showed unilateral nipple inversion and pain. One patient (n = 1, 8%) showed swollen and redness. The 2 patients showed a lesion in the gland around the nipple present as an irregular shape and unclear boundary hypoechoic mass.Nipple wart (n = 2, 15%): Two patients showed a unilateral soft exogenous neoplasm. Both of the patients showed a hypoechoic wart; the echo was similar to the nipple, the border was clear, and had no blood flow in the wart.Nipple Dysplasia (n = 3, 23%): Accessory nipple (n = 3, 23%). Two patients (n = 2, 15%) had accessory nipples in the subcoastal area, 1 patient (n = 1, 8%) in the areolar. All of the patients' sonographic features were the same as the nipple.The positive predict value (PPV) of the clinical symptoms: Erosion and discharge are both 75% (P < 0.05). The PPV of the US manifestations: irregular shape, indictinct margin, abundant blood flow, microcalcification, thicken skin in diagnosing malignant lesions are 60%,60%,60%,100%,100%, respectively (P < 0.05).

CONCLUSIONS

The characteristic sonographic features together with clinical symptoms contribute to the diagnosis of nipple lesions.

Analysis of the radio-pathological factors of triple negative breast cancer and determination of risk profiles

OBJECTIVE

Triple-negative tumors are the most aggressive type of breast cancer. We aimed to analyze the main radiologic and histopathologic factors of these tumors to create a risk profile.

MATERIALS AND METHODS

We analyzed data from 140 patients diagnosed with triple-negative breast cancer between January 2007 and December 2016, with follow-up through April 2018. We analyzed the following variables in the breast MRI done for staging: size, necrosis, associated findings, adenopathies, and perfusion and diffusion parameters. We analyzed the following variables in histopathologic studies of biopsy specimens: histological type, Scarf-Bloom, Ki67, and p53 in the infiltrating component as well as in the in situ component. We analyzed the following variables in histopathologic studies of positive lymph nodes and surgical specimens: size, lymphovascular/perineural invasion, and microglandular adenosis. We analyzed the relation between the radiologic and histopathologic factors and recurrence and disease-free survival.

RESULTS

MRI tumor size>25mm, non-nodular enhancement, breast edema, areola-nipple complex retraction, and lymph-node involvement were associated with recurrence and lower disease-free survival. Invasive lobular carcinoma, postsurgical size>20mm, and p53<15% were also associated with recurrence and lower disease-free survival. Histologically positive lymph nodes were associated with a greater percentage of recurrence and lymphovascular invasion and with lower disease-free survival. The multivariate analysis found that the variables MRI size>25mm, non-nodular enhancement, adenopathies on MRI, and p53 expression <15% were independent predictors of lower disease-free survival.

CONCLUSIONS

In triple-negative breast tumors, factors associated with lower disease-free survival are non-nodular enhancement, size>25mm, and adenopathies on MRI, and p53 expression <15% on histopathologic study.

Erratum: Role of breast magnetic resonance imaging in predicting malignant invasion of the nipple-areolar complex: Potential predictors and reliability between inter-observers: Erratum

[This corrects the article DOI: 10.1097/MD.0000000000007170.].