I. Detection of breast calcification
With the increasing maturity of high-definition mammography and high-frequency ultrasound technology, for more and more women with clinically unpalpable lumps, in addition to various manifestations of breast diseases found during the examination, about 2/3 of them can have calcified shadows in the breast.
Second, calcification occurs in the manifestation of cancer cells
It often occurs in the area of degenerative necrosis of cancer cells, which is manifested as heaps of sand-like calcification, and sand-like calcification can be seen at the edge of the lump. This is because calcification after necrosis of tumor cells occurs in the necrotic debris at the edge of infiltrative masses. Therefore, calcification around the lesion has the same clinical significance. Clusters of fine particulate calcifications with irregular calcifications in clusters of calcifications may be considered to have malignant diagnostic value when no mass shadow is shown. Combined with clinical, if the breast adds the display of tiny calcified foci, it has some significance for early detection of breast cancer.
III. Characteristics of calcification in breast cancer by high frequency ultrasound and X-ray photography
Calcified grains are small, with a diameter of 10-500 μm, but generally not more than 1000 μm. On X-ray, the visibility of the naked eye is about 150 μm, and magnification is often needed to identify calcified foci in dense breast or mammogram with poor background.
Improvements in the performance of ultrasound instruments and the use of high frequency probes have made it possible to observe microcalcifications with ultrasound technology. The detection rate of microcalcifications in breast cancer is 56% and 35% for high-frequency ultrasound and radiography, respectively. However, it has also been reported that ultrasound and MRI are not easy to detect microcalcifications due to their limitations.
Different types of calcifications and their significance
I. Typical benign calcifications
1, skin calcification: typical ones have translucent changes in the center, atypical ones can be identified with the help of tangential bit projection.
2.Vascular calcification: tubular or track-like.
3, coarse or bract-like calcification: the characteristic manifestation of calcification of fibroadenoma.
4, coarse rod-like calcification: continuous rod-like, occasionally branching, usually larger than 1 mm in diameter, may show central translucent changes. These calcifications are commonly seen in secretory lesions such as: plasmacytoid mastitis and ductal dilatation.
5. Round calcifications: If they are multiple, they may vary in size. For those smaller than 1 mm, they are often located in lobular alveoli. For those smaller than 0.5mm, they may be called punctate calcifications.
6, ring or eggshell-like calcification: the ring wall is very thin, often less than 1mm, and is calcification deposited on the surface of spherical objects. It is seen in fat necrosis or cysts.
7, hollow calcification: size can range from 1mm to 1cm or even larger, with smooth edges, round or ovoid, and a central hypodense. The thickness of the wall is greater than the annular or eggshell-like calcification. Commonly seen in fat necrosis, calcified remains in ducts, and occasionally in fibroadenomas.
8. Milk-like calcification: calcification within the cyst. In the axial position, the manifestation is not clear, it is fluffy or indefinite shape, in the lateral position the boundary is clear, according to the different morphology of the cyst and the manifestation is semilunar, crescentic, curvilinear or linear.
9. Suture calcification: caused by calcium deposition on the suture material, especially common after radiotherapy. Typically, it is linear or tubular, and knot-like changes are often seen.
10, dystrophic calcification: often seen on the breast after radiotherapy or trauma, with an irregular calcification pattern, more than 0.5 mm, and hollow tubular changes.
11.Dotted calcification: round or ovoid calcification with diameter less than 0.5mm and clear edges.
Second, calcification that cannot be characterized
Amorphous or vague calcifications, often round or lamellar, very small and vague, the nature of which cannot be determined morphologically.
Third, highly malignant possible calcifications
1, polymorphic and inhomogeneous calcifications (granular punctate calcifications): more suspicious than indeterminate calcifications, their size and morphology vary and their diameter is often less than 0.5 mm.
2.Linear or linear branching calcification (cast calcification): fine and irregular linear calcification, often discontinuous, with diameter less than 0.5mm. These signs suggest that the calcification is formed from the ductal lumen invaded by breast cancer.
Distribution pattern
1.Clusters: Previously, this was considered a malignant distribution pattern, but now it is considered a neutral distribution pattern, both benign and malignant. It refers to the clustered calcifications less than 2cm cubic area.
2, linear: arranged in a linear pattern, visible branching points
3.Segmental-like: It often suggests that the lesion originates from one duct and its branches, or it may be a multifocal carcinoma occurring on one lobe or one segmental lobe. Although benign secretory lesions may also have segmental-like calcification, if the morphology of calcification is not characteristically benign, it is first considered as malignant calcification, and when it is not accompanied by a mass, most of them are ductal carcinoma in situ.
4.Regional: Calcifications in a larger area cannot be described by segment-like and cluster-like.
5.Diffuse or scattered: randomly scattered in the whole breast.
V. Attention
1. When encountering a relatively large number of calcifications, what is important is not the number of calcifications, but the morphology of each calcification. If each calcification is small but round or clearly demarcated from other calcifications, regardless of the number, even if there are several within 2 cm, they are usually benign, such as those that are “randomly scattered throughout the breast”.
In addition to plasmacytoid mastitis, which is easily misdiagnosed as cancer, traumatic fat necrosis is more similar to breast cancer, with local fat necrosis forming a lump with burrs and calcification. However, this kind of calcification is less likely to occur and will be limited to the localized lesion without extensive extension.
The value of breast calcification in breast cancer diagnosis
I. Incidence of calcification in breast cancer
Calcification is one of the common imaging manifestations of breast cancer. Certain specific forms of calcification are risk factors for breast cancer. Statistics show that 65% of breast cancers have calcification, and 70% of them are malignant calcification.
The only X-ray sign of early breast cancer
Cluster-like microcalcifications are often the only X-ray signs of early breast cancer. The nature and extent of the lesion can be reflected by the shape, size, number and density of microcalcifications. Microcalcifications can be located in or around the lump, with a total number of 6 to 15, with uneven density and varying size.
Mammography can improve the diagnosis rate of occult cancer, microscopic cancer (less than 10mm in diameter) and early cancer. It is difficult to characterize lumps less than 10mm in diameter, but fine sand type calcification is often an alarm of malignant lesion; if there are signs such as disorder of surrounding structures, bilateral asymmetry and thickening of vascular shadow at the same time, malignant lesion is more likely.
Third, the formation of microcalcifications in malignant breast lesions
The large number of microcalcifications per unit area of breast malignant lesions may be caused by the combined effect of necrosis of cancer tissue and secretion of cancer cells. The different densities and sizes among calcification points may be due to the different duration of calcium salt deposition, and the calcifications formed first with time are relatively denser and larger in volume.
Fourth, the difference between benign and malignant calcification
Compared with benign calcifications, the average density of malignant calcification group is lower, and the density and size are of greater value in differentiating benign and malignant breast diseases. The distribution of microcalcifications in mammograms seems to be irregular, but when pathology reveals that the cancer occurs in the terminal ducts, calcifications may be located in a large area of necrotic tissue or among cancer cells, or they may exist in the superior ducts or in the bifurcation of the ducts or in the adjacent alveolar lumen.
V. Formation of regional calcification of cancer foci
Regional calcification of cancer foci may be of fine sand type or mixed type, and intra-ductal calcification of worm type, which may be related to the abnormal secretion of tumor draining along the duct.
When the cancer is located in larger ducts, calcifications away from the focal area are often located in the peripheral next level ducts and are mainly of fine sand type, which may be produced by abnormal metabolites of cancer cells or the reflux of cancer cells stimulating the terminal ducts and glandular vesicles. The number is large, the particles are fine, and the edges are rough, which can be located inside or outside the block shadow, suggesting malignancy.
Principles of morphological analysis of mammogram mammogram calcification
I. In conventional mammography with mammography, smaller calcifications may be missed or difficult to determine because of the overdensity of the breast gland, the overlap of tissues and the inherent resolution limitations of the equipment.
Second, the size, morphology, density, number and distribution of calcifications may have some correlation with their benignity and malignancy, which can be used as a reference factor for differential diagnosis of benign and malignant calcifications. The more the number of microcalcifications in a certain volume range, the more the number of microcalcifications in a certain volume range, when ≥5 grains of microcalcifications are clustered in a 1cm2 range, the possibility of breast cancer is high; <5, benign lesions; but calcified particles <0.5mm in diameter, with different depths of density, point-like, branching-like or mud-like calcifications, with microcalcifications in or around the mass, are breast cancer. The morphology is: fine granular, sediment-like, fine-linear, bifurcated, etc. And a larger number of specific calcifications can help to diagnose breast cancer. The differential diagnosis of benign and malignant microcalcifications in the breast is a very difficult problem. Microcalcifications are not a specific sign of breast cancer, but they have an important differential diagnosis between benign and malignant.
Third, mammograms fail to show mass shadows (mostly dense glands) but only calcifications, which have a great overlap in both benign and malignant lesions; breast cancer calcifications are mostly located in the necrotic area of the tumor, but also in the peritumor connective tissue, and there are also calcifications without masses. A single form of microcalcifications without a mass has a significantly higher malignancy rate when they are present in or around the mass. If, in clusters of microcalcifications, the size of the calcified particles is within the diameter range of 0.01-0.5 mm, the density varies in depth, and the morphology is varied, with point-like, branch-like, or both mud-like calcifications, the diagnosis of malignancy is made regardless of whether there is a mass in the cluster of calcifications.
Fourth, the application of mammography for localization puncture of occult lesions, which has significantly improved the detection of breast cancer.
V. Diseases that often have calcification in the pathological examination results of clinical breast cases.
Breast cancer: among them, intraductal carcinoma, lobular carcinoma in situ, intraductal carcinoma with limited infiltration, intraductal papilloma with limited carcinoma, ductal epithelial atypical hyperplasia cell carcinoma, invasive ductal carcinoma, invasive lobular carcinoma.
Benign breast lesions: among them, mastopathy, fibroadenoma, intraductal papilloma, ductal dilatation and cyst, lobular hyperplasia, lobular hyperplasia with atypical hyperplasia.
Intraductal carcinoma of the breast is predominantly ductal-type calcifications or calcifications along the course of the ducts in the radiographs, while simple carcinoma and invasive ductal carcinoma are predominantly granular or pinpoint calcifications in the radiographs, but coarse calcifications are also seen in the radiographs of breast carcinoma.
For the further diagnosis of patients with clustered calcification
I. Diagnostic methods of breast calcification
X-ray-guided coarse needle aspiration biopsy, ultrasound-guided coarse needle aspiration biopsy and X-ray-guided metal wire localization excision biopsy have been performed for occult lesions at home and abroad. In contrast, ultrasound is inferior to X-ray in showing microcalcifications in the breast; in terms of the completeness of excisional biopsy at the point of calcification in the breast, X-ray-guided metaline localization surgical excisional biopsy is superior to X-ray-guided coarse needle aspiration biopsy.
Preoperative localization of the calcification point in the breast with a mammography breast machine
The patient is placed in a standing or sitting position, and the breast is fixed on the mammography pallet so that it is in a compressed state. The location of the intra-mammary calcification point is positioned in the coordinate hole, and a puncture needle with a metal locator wire is inserted through the skin and removed when the tip of the needle reaches and slightly exceeds the calcification point. In each case, one to two localization wires are placed, and lateral and axial views are taken for reference during surgery.
III. Surgery
The patient is placed in the supine or lateral position, and the incision is designed to facilitate the removal of all the calcification points and to take into account the shape of the breast, with routine disinfection, local anesthesia or local anesthesia reinforcement, and the procedure is always guided by the metal positioning wire. The procedure is always guided by a metal positioning wire. We strive to remove all microcalcifications in the breast that are negative to clinical palpation. After excision of the lump, the lump was sent to the diagnostic department for photography to make sure that all calcified spots were included in the specimen before sending it to the pathology department for diagnosis, and if any calcified spots were found to be unexcised, they should be excised. All the metal positioning wires were removed during the operation, and there was no fracture or leftover phenomenon.
Mammotome biopsy of breast calcification