If you have had an MRI scan for your breast, you are probably wondering what it means if you had an enhancement on the mri. There are three ways that an mri can show enhancement. One of them is a clumping of the tissue, another is a regional non-mass enhancement, and a third is a ductal or linear enhancement.
Normal fibroglandular breast tissue shows enhancement
Mammography is an imaging tool used to detect breast cancer. It is a non-invasive technique that uses a contrast agent to provide an image of the breast. The breast contains fatty, fibroglandular, and glandular tissue. Each person has a different ratio of these tissue types. However, the amount of fibroglandular tissue in the breast is related to the risk of breast cancer.
Breast MRI is also a diagnostic tool that detects cancerous and benign lesions. These lesions are classified as mass, focus/foci, and non-mass like enhancement.
Typically, normal fibroglandular tissue enhances to varying degrees. In some instances, this is not suspicious. Instead, it can be a sign of a problem, such as lymphadenopathy.
Various studies have shown that women with high BPE are at an increased risk of developing breast cancer. However, this association is still being evaluated.
Linear non-mass enhancement
The morphology and kinetic behavior of non-mass enhancements in breast MRI is a matter of interest. Although most research has focused on the characterization of mass-enhancing lesions, only a few studies have addressed the morphology and enhancement kinetic features of non-mass enhancements. It is important to understand the differences between these two types of lesions so that a proper diagnosis can be made.
Non-mass enhancements are characterized by a heterogeneous appearance on breast MRI. They can range from focal and segmental to diffuse and clumped internal enhancements. In addition to their morphological characteristics, they also have dynamic and temporal behaviors that can provide a valuable diagnostic tool. However, systematic classification of these lesions is not in place.
We evaluated the morphological distribution and kinetic behavior of NME in a series of 177 consecutive patients receiving breast MRI for evaluation. A total of 175 NME were identified in the study. This included 120 cases of benign and 61 of malignant NME.
Regional non-mass enhancement
There are many benign processes that manifest as non-mass enhancement (NME) in breast MRI. These processes include fibrocystic changes, hormonal stimulation, and inflammatory changes. A large number of malignant processes may also show signs of non-mass enhancement. Several MRI features can be used to diagnose both benign and malignant NME.
Typical morphological features of non-mass lesions are segmental distribution, focal pattern, and clustered ring enhancement. Each morphology had a specific descriptor within the 5th edition of the BI-RADS lexicon. The study evaluated the sensitivity, specificity, positive predicting value (PPV), and negative predicting value (NPV) of each of these morphological characteristics.
Segmental distribution is associated with a high specificity. It is more likely to be indicative of malignancy. However, this characteristic was less pronounced in benign NME.
The ACR lexicon describes three categories of non-mass-like enhancement. These include segmental, homogeneous, and stippled. Each of these categories is separated from Background Parenchymal Enhancement (NME). Non-mass-like enhancement is considered to be more important than NME for detecting cancer.
While there are several benign conditions that may also enhance in a similar fashion to cancer, it is important to be aware of the pitfalls of pathologic nonmass-like enhancement in high-risk premenopausal women. It is important to have an MRI-guided biopsy when a suspicious nonmass-like enhancement is detected.
The most common type of nonmass-like enhancement is clumped. It is a cobblestone-like enhancement with a diameter of less than 5 mm. This pattern is associated with invasive ductal carcinoma. Approximately 60% of lesions with clumped enhancement will have cancer.
Clumped enhancement in breast MRI is a pattern which should be viewed on several views during an MRI study. It is not to be confused with the beaded or grape-like appearance of non-mass enhancement. In contrast, clumped enhancement is described in the BI-RADS lexicon as a group of punctate enhancing foci or a cobblestone like appearance.
The study by DeMartini WB, Okamoto S, and Ikeda D studied internal enhancement patterns in breast MRI. Specifically, the researchers sought to evaluate the accuracy of three major morphological distributions in predicting benign and malignant lesions. Using the fifth edition of the ACR BI-RADS lexicon, descriptors were developed and interpreted.
The study evaluated morphological distributions in terms of heterogeneity, segmental, and focal distribution. These characteristics were assessed using the binomial logistic regression model, which had a sensitivity of 74.3% and a specificity of 79.2%. For the analysis, post-contrast axial images were obtained.