Breast calcifications can be benign, suspicious, or malignant; this distinction is made according to their mammographic characteristics, taking into consideration some clinical parameters (morphology, size, number and distribution).
Usually, breast calcifications of benign appearance are isolated and round, while those of malignant conformation are heterogeneous in shape and density, clustered and pleomorphic.
Calcium salt deposits are often related to benign breast tissue changes and, in most cases, are harmless. Sometimes, however, microcalcifications (i.e. small opacities) can become pre-tumor alarm signals : about 30% of malignant breast neoplasms are diagnosed only thanks to the presence of these alterations.
When breast calcifications have characteristics of certain benignity, normal mammographic controls are continuedannuals; if there are elements of diagnostic doubt, instead, it is necessary to proceed with the biopsy for the histological definition .
Breast calcifications are deposits of calcium salts . These lesions are painless and usually not palpable.
The most appropriate technique for their visualization is mammography : breast calcifications are easily detectable due to their radiographic contrast with respect to breast tissue.
These small mineral deposits can be observed in both normal and pathological breasts . For this reason, their characteristics must be carefully analysed.
How Can They Be Identified?
Changes in the density of the mammary gland can be identified palpation by the expert clinician (if the lesion is located superficially and has a diameter of at least 1 cm) or by diagnostic imaging.
Their finding is possible above all during the mammographic examination , a routine investigation useful for the early diagnosis of breast cancer. In fact, mammography can identify small anomalies of glandular density (less than 1 cm in diameter), even if located in deeper sites.
At the time of diagnosis, breast calcifications must be described with precise criteria:
- Morphology: shape, margins, contours and dimensions;
- Localization within the mammary gland;
- Relationships with surrounding tissues.
From a mammographic point of view, breast calcifications can be an isolated finding or associated with the presence of parenchymal nodules or distortions . In addition to these anomalies, it is also possible to find dilation of the ducts, enlarged lymph nodes , thickening or retraction of the skin profile and modifications of the areola . As far as diagnosis is concerned, it is important to evaluate their evolution over time, comparing mammograms with those of previous years.
Breast calcifications can indicate benign situations , found, for example, in inflammation of the lactiferous ducts (galattophorites) or in a normal aging process of the mammary gland. Therefore, these lesions are not necessarily the expression of a tumor process.
In some cases, however, breast calcifications can become an indication of an area of the mammary gland undergoing alteration; in this sense, they represent the warning light for a neoplasm , on which to intervene as soon as possible from a therapeutic point of view.
Calcifications have different morphological characteristics depending on their origin, so all the parameters (shape, density, number and distribution in the mammary gland) must be evaluated with particular attention, which allow us to draw indications as to whether they are benign or not.
In general, large, rounded and scattered formations are more common in benign breast pathologies, while small “iron filing ” opacities are more associated with neoplastic processes.
As far as breast cancer is concerned , the most significant pathological picture is represented by rounded nodules with irregular outlines and blurred margins, often associated with microcalcifications.
As we have seen, the main criterion used to differentiate benign from malignant calcifications is size . The opacities from deposits of calcium salts also tend to have regular margins and homogeneous density.
In fibroadenomas , coarse calcifications with a diameter of a few millimeters are typically and commonly found, defined as “geographical” or “popcorn ” . Other moderately sized mineral deposits can be found on the walls of cysts or in the sites of cellular necrosis processes (absolutely harmless) resulting from trauma to the breast tissue, surgery or previousinflammations . Breast calcifications can also be a result of ageing : these lesions depend on the deposition of fat and calcium salts in the breast tissue.
Benign breast calcifications are also vascular ones (calcium deposits in the arteries or veins within the breast), elongated in two parallel lines or in a ring with respect to the vessel lumen.
A common finding is the appearance of breast calcifications after radiation therapy . Furthermore, it should be noted that the pigments of tattoos, deodorant residues and certain cosmetics are often radioopaque and can sometimes simulate the presence of a benign calcification.
The causes of breast calcifications include the pathological processes associated with the proliferation of cells within the lactiferous ducts, in its various degrees of evolution (from more or less atypical hyperplasia, to intraductal neoplasms, up to actual infiltrating ductal carcinomas ).
The shape and distribution of the microcalcifications allow to draw indications on the possible presence of a precancerous disease or breast cancer . In neoplastic pathology, mineral deposits detected by mammography are appreciable in about 30% of carcinomas.
These formations can be found within a nodule or near it. Furthermore, in some cases, microcalcifications are the only anomalies that can indicate the presence of a tumor.
These lesions generally have a size that varies between 0.1 mm and 0.5 mm: the dimensions are, however, extremely variable and can be influenced by the breast pathology in progress. In some carcinomas, such as ductal carcinoma, in fact, the mineral deposits can be linear and larger.
Breast micro calcifications doubtful or suspected of malignancy (granular, linear, or branching) should be studied under direct radiographic magnification.
Importance Of Early Diagnosis
The detection of breast calcifications with mammography, before the oncological pathology manifests itself clinically, is very important. The removal of these neoplastic tissues in the initial stage , very often still non-invasive, prevents the development of a more serious and dangerous tumour.
The mammography can then be completed, depending on the case, also by ultrasound which is not, however, able to identify the micro calcifications, visible only with mammography. On the other hand, breast ultrasound is capable of detecting small nodular formations that may be invisible on mammography. For this reason, the two exams are considered complementary.
Characteristics And Differential Diagnosis
When a mammography is performed, a series of aspects relating to calcifications are evaluated with particular attention, such as the shape, density, number and distribution: these parameters allow the radiologist and breast specialist to obtain useful information on the small mineral deposits and to define the benignity or otherwise of the situation.
Breast calcifications can result from:
- Irregular (suspicious);
- Round (more common in benign pathology);
- Granular or powdery (suspicious);
- Point-like in appearance;
- Linear, rod-shaped and branched (suspected);
The irregular shape is the most significant, as it has a high predictive value (about 80% of cases) of carcinomas with micro calcifications. Of less concern, on the other hand, are the rounded and scattered mineral deposits in the breast tissue, which are often the residue of past puerperal mastitis .
The distribution of calcifications plays an important role in the clinical diagnosis. The most suspicious lesions are massed or “iron filing” micro calcifications, which are irregularly shaped and concentrated in the lactiferous ducts.
Even very small lesions, but distributed over the entire glandular area or in extensive sectors of the gland, not grouped together, especially if bilateral, are generally benign.
Numerous breast calcifications located in a small area of the breast parenchyma may have a prognostic significance of a neoplastic type.
The density of breast calcifications is usually high, but can vary from one lesion to another.
If calcifications are found during the mammography, the doctor (radiologist) can indicate the execution of more in-depth tests, in order to exclude any diagnostic doubts and have the most precise response possible.
In the presence of suspicious alterations, it therefore becomes necessary to take a breast biopsy to define the nature and histopathological characteristics of the lesion.
- Breast calcifications that are benign in nature generally do not require any type of investigation, but it is advisable to perform a control mammogram once a year.
- If mildly abnormal breast microcalcifications are found , they can be classified as “probably benign” . For the correct definition of the pathological condition, a slight atypia may make further tests necessary. “Probably benign” breast calcifications are harmless in about 98% of cases. Typically, a follow-up with mammography is indicated for these lesions every six months, for at least one year, in order to monitor that no changes are occurring in the tissue.
- If these deposits are irregular in shape or size or are tightly attached to the breast tissue, they may suggest that they are early manifestations of a tumor, often “in situ” (non-invasive); in these cases, more in-depth investigations should be carried out. Usually, histological sampling by means of a stereotactic or surgical biopsy, with preoperative radiological localization, is indicated. The tissue samples containing the micro calcifications thus collected are then analyzed under the microscope by the specialist in pathological anatomy, who will provide for the complete evaluation of the histotype, the degree of differentiation of the lesion and, if necessary, the functional characteristics by means of antigen reactions -antibody by immunohistochemical methods. In some cases, tissues can be the subject of molecular studies.
If the presence of tumor cells is confirmed in the amount of breast tissue containing the calcification, the doctor can prepare the most appropriate surgery for the case to eliminate the residual neoplastic tissues.