Malignant tumors of the mammary gland

The most common malignant breast cancer is breast cancer - this is the disease with which all benign processes in the mammary gland are differentiated.

If you suspect a malignant process, the ultrasound of the mammary glands allows you to estimate the location, quantity, size, shape, echostructure, contours, additional acoustic effects, the condition of the ducts and surrounding tissues, including skin changes, and the presence and nature of vascularization. Most lesions of the breast are detected in the upper outer quadrant. In this quadrant, up to 50% of all cancers of the mammary glands are located. This incidence rate of this region is apparently associated with a high concentration of terminal milk ducts.

Localization of malignant tumors in other quadrants is as follows:

• lower inner quadrant - 5%;
• lower outer and upper inner quadrants - 15%;
• lower outer quadrant - 10%;
• the central arrangement behind the areola is 17%.

Breast cancer can be in the form of a diffuse form (edematous-infiltrative cancer) and nodular form.

[1], [2], [3], [4], [5]

Nodular form of breast cancer

Possible as one or more nodes. The size of the tumor is related to the growth rate and the time of their detection. Proper determination of the size of the tumor is important for choosing the tactics of treatment. Everyone knows a weak correlation between clinically, radiographically and mammographically determined and true histological sizes of the lesions in the mammary gland. Ultrasound of the mammary glands gives the best ratio of the sizes of malignant tumors of the mammary gland in comparison with the data of X-ray mammography and their clinical definition. When comparing tumor sizes with pathomorphological data, the correlation coefficient for one data is 0.77 for palpation, 0.79 for x-ray mammography and 0.91 for ultrasound of the mammary glands. According to other data - 0.79 for clinical measurements, 0.72 for x-ray mammography and 0.84 for ultrasound of the mammary glands.

With echography, the tumor is measured in three projections. In most cases, the nodal forms of breast cancer are a hypoechoic formation. Ehostruktura can be varied and depends on the presence of areas of necrosis, fibrosis, calcifications, tumor vessels. Behind the malignant tumors, an acoustic shadow can be determined.

There is a specificity of echographic images of two morphological variants of the nodular form of breast cancers - well-delimited tumors with an expansive growth pattern and poorly delimited cancers (scirrhous or stellate) with infiltrative growth type.

The shape and contours of these tumors are evaluated according to the nature of their growth.

With infiltrative growth, the tumor often has an irregular shape, the unevenness of its contours is noted due to the involvement of many structures of the breast in the pathological process. The contours of the tumor become even more uneven when combined with desmoplasia (secondary fibrosis) of the surrounding tissues. Desmoplasia is a response to the processes of tumor infiltration of surrounding tissues and is characterized by increased echogenicity of surrounding fatty tissue in the form of an uneven hyperechoic rim around the tumor and other changes caused by contraction of fibrous fibers and stroma.

In the expansive (expanding) nature of growth, the tumors have a regular round or oval shape, well-defined or slightly blurred contours. The tumor spreads the surrounding tissues, while their compression and deformation occurs, but not destruction.

When the sensor is pressed on a tumor with an expansive growth pattern, a slight change in its shape and a symptom of "slipping" or a shift in the formation of the surrounding tissues are noted. This is never observed when compressing solid infiltrating masses.

With echography, you can differentiate your own tumor boundary from fibrotic reactions (desmoplasia) of surrounding tissues. With palpation and X-ray mammography, it is impossible to differentiate desmoplasia from a tumor. On X-ray photographs, desmoplasia looks like part of a malignant tumor.

Microcalcinates combine with breast cancers in 42% and are easily detected by X-ray mammography. In the literature, the question of the possibilities of echography in the detection of makrokaltsinatov mammary glands was widely discussed. When using high-resolution ultrasound equipment with properly focused sensors, it is possible to detect tiny echogenic points within the formation that correspond to the mammographic image of calcinates. Almost always small calcites do not give an acoustic shadow. Echographically, microcalcinates are difficult to differentiate against a background of echogenic glandular tissue or tissues with a large number of reflecting surfaces. With x-ray mammography, calcifications are much better, so the possibilities of ultrasound in this issue are not given much clinical significance. At the moment, the role of echography is reduced to the identification of structures that include calcinates, for example, calcium milk in microcasts, in-flow calcification, calcifications within the formations.

Sensors equipped with a water nozzle allow visualizing changes in the skin of the breast. Surface-located malignant tumors of the breast can cause not only changes in the subcutaneous tissue, but also involve the structure of the skin in the process. Involvement of skin in the tumor process can manifest itself in the form of thickening, deformation and changes in the echogenicity of the skin. Less superficially located cancers can cause skin changes in the form of a violation of its normal orientation and constriction of Cooper ligaments.

For a long time, distal weakening was considered as the most constant sign of tumor malignancy. However, in the works of Kabayashi et al. (1987) it was proved that the occurrence of acoustic effects behind tumors is caused by the presence and amount of connective tissue. Acoustic shadow is determined in 30-65% of cases.

Behind the malignant tumor of the mammary gland, additional acoustic effects may or may not be marked distal, as in the medullary and mucinous forms of cancer. Distal reinforcement can also be seen behind malignant tumors growing in the cyst cavity, as well as behind some infiltrative ductal cancers.

Ultrasound criteria do not allow differentiating histological types of breast cancer.

Nodular forms of infiltrative breast cancer

Crayfish, giving a star pattern, regardless of the form (infiltrative, protocol, lobular) have a scirrhous structure. Most often in the center of such tumors, the areas of fibrous, sometimes hyalineized stroma, predominate. On the periphery of the tumor there are complexes of tumor cells of epithelial nature. Less common is the uniform distribution of parenchyma and stroma in the node of the tumor.

The boundaries of the tumor during echography are always fuzzy due to the pronounced infiltration of the surrounding tissues. Stellar shape is due to the growth of a tumor of Cooper ligaments. One of the most common echographic features in the case of scirrhous forms of crayfish is acoustic shade.

It was found that the predominance of the connective tissue component in the tumor promotes a greater attenuation of ultrasonic waves, as a result of which the visualization of tissues located behind the tumor is impaired. Scirrhous form of crayfish is characterized by a high content of connective tissue (up to 75%).

One of the variants of the invasive, or infiltrating, malignant process in the mammary glands is infiltrative ductal cancer. Infiltrative protocol cancer can have extensive intra-flow distribution, which can not always be determined during surgery and can subsequently give local relapses. From this point of view, it is very important that the border of surgical intervention pass beyond tumor infiltration. The decisive factor in the definition of tumor infiltration of the ducts is the morphological conclusion. X-ray mammography has good prognostic capabilities in determining the prevalence of intra-cellular tumors. Well-differentiated at x-ray mammography microcalcinates of a displaceable structure, this process is classified as suspicious for malignancy.

Color Doppler mapping can be used to differentiate blood vessels from ducts, since both have the form of tubular hypoechoic structures.

Nodular forms of cancer with an expansive growth pattern (well-delineated)

Nodular forms of well-delineated crayfish include medullary, mucinous, papillary and some ductal cancers and sarcomas (which constitute a small percentage of malignant breast tumors). Although these tumors squeeze surrounding tissues during their growth, they practically do not cause or cause minimal fibrotic changes in surrounding tissues. Some tumors demonstrate distal reinforcement. With the help of echography it is impossible to differentiate these well-delineated crayfish from benign solid formations.

Medullary and mucinous (colloidal) cancers can resemble a complex of cysts with hypoechogenic contents. Medullary crayfish have a round or lobular form of a cystic-solid structure, are well delimited from surrounding tissues, do not have a capsule. As the medullar cancer grows, anechoic zones of necrosis form with areas of organized and fresh hemorrhages. Often an anechoic rim is identified, which according to the morphological evaluation corresponds to the zone of active tumor growth. Distal strengthening is due to the predominance of a solid component of the tumor with a lesser content (less than 25%) of connective tissue structures. With an increase in the size of the tumor anterior to the formation may appear a wide rim of increased echogenicity. At large sizes the tumor is fixed to the anterior thoracic wall, it can ulcerate. A small tumor is clinically reminiscent of fibroadenoma. Medullary cancers are extremely rare after menopause.

Colloid cancers are rare, slowly growing tumors whose cells produce a mucous secret. These tumors occur at the age of 50-60 years. When echography, their shape can be round or oval, the boundaries - from good differentiation to diffuse. Calcinates can be determined. Secondary changes are not typical. Hemorrhagic changes in the internal structure are atypical.

Cystic or intracavitary cancer is a rare form of a malignant tumor of the mammary gland. Histologically, this is a papillary cancer that occurs from the cyst wall. The ultrasound image can be represented by a complex of cysts with thickened walls or with solid outgrowths that extend into the cavity of the cyst. The second variant of the cavity form of cancer is represented by a picture of a cyst whose wall is deformed from the outside due to infiltration from the side of the growing tumor. In both cases, cysts can have echogenic contents. Cytological examination of aspirates gives more information when it is obtained from a site containing a solid component, since the amount of tumor cells in the liquid content can be very small. The cavity form, like a solid papillary carcinoma, is more common in older women. With echography, these tumors can not be well differentiated with their benign analogues.

Although cancer is usually characterized by the appearance of hypoechoic formations, ultrasound findings can be limited to simply heterogeneous violations of architectonics without obvious formation.

Diffuse form of breast cancer (edema-infiltrative)

Osteo-infiltrative form of cancer is a consequence of infiltration of lymphatic vessels of the breast by tumor cells. Clinically, the edematous-infiltrative form is manifested by reddening and thickening of the skin, which becomes like a lemon crust. When echography is determined thickening of the skin, increased echogenicity of the underlying fat and visualized network of hypoechoic, parallel and perpendicular to the skin of tubular structures (enlarged and infiltrated lymphatic vessels). Other echographic changes are characterized by increased echogenicity of the parenchyma of the mammary gland with the impossibility of differentiation of its constituent parts. Distal acoustic shadows can mask the subjects to be educated. The edematous-infiltrative form of breast cancer does not have specific echographic or mammographic features, which does not allow to differentiate it with a benign analogue - a diffuse form of mastitis.

[6], [7], [8], [9], [10]

Other malignant processes of mammary glands

Metastases in the mammary gland are from 1 to 6% of all malignant processes of the mammary glands. Primary tumor focus can be localized in the lungs, gastrointestinal tract, pelvic organs, bladder or contralateral mammary gland. Metastatic tumors in the mammary gland can be single, but much more often multiple. They can palpate or not. The lesion can be unilateral or bilateral, involving or without lymph nodes. With ultrasound of the mammary glands, the formation of a non-uniform structure is determined, hypoechoic, rounded with fairly even and clear contours. The appearance of a hyperechogenic capsule (desmoplasia sites) is atypical.

Unlike primary tumors, metastases are usually located in the subcutaneous zone. Metastases can be the first manifestation of cancer in a patient without a primary focus or are found in the mammary gland in the late stages of the disease. In both cases, an aspiration biopsy is necessary to establish a diagnosis, since mammographic and echographic findings are not specific. With X-ray mammography, well-defined numerous rounded blackouts are defined that do not differentiate well with cysts.

Melanomas, sarcomas, lymphomas, leukemias, leukemias, myeloma can also cause breast damage. In the literature there are descriptions of the plasmocytoma of the mammary gland.

Sarcoma is an extremely rare lesion of the mammary glands. It arises most often from mesenchymal elements of a benign tumor, such as phylloid fibroadenoma, or from the mammary gland stroma. According to the literature, liposarcoma is 0.001 to 0.03% of malignant breast tumors. A single case of osteogenic breast sarcoma is described. Mammographic and echographic pattern is not specific.

Dopplerography of breast diseases

Echography when combined with the Doppler method can detect newly formed tumor vessels. Color Doppler mapping and energy dopplerography are considered as a promising addition to echography for differentiating the breast tissue. With color Doppler mapping around and inside many malignant tumors, a much larger number of vessels can be identified than benign processes. According to Morishima, color doppler mapping from 50 cancers revealed vascularization in 90% of cases, color signals were located peripherally in 33.3% of cases, centrally in 17.8%, chaotically in 48.9%. The ratio between the area of vascularization and the size of education was less than 10% in 44.4% of cases, less than 30% in 40% of cases and more than 30% in 11.6% of cases. The average size of the tumor in which the color signals were detected was 1.6 cm, while at a tumor size of 1.1 cm there was no vascular recording at all. In the analysis of 24 cancers of the breast, the number of poles of vascularization was taken into account, which averaged 2.1 for malignant and 1.5 for benign formations.

When attempting a differential diagnosis of benign and malignant processes using pulse dopplerography, the following factors should be considered:

• large proliferating fibroadenomas in young women are well vascularized in 40% of cases;
• small cancers, as well as some specific types of cancers of any size (such as mucoid carcinoma) may be unvascularized;
• the detection of tumor vessels depends on the technical capabilities of the ultrasound device to record low rates.

The ultrasound method can detect changes in lymph nodes in various pathological processes in the mammary glands, determine their size, shape, structure, and the presence of a hypoechogenic rim. The revealed rounded hypoechoic formations from 5 mm in diameter can be the result of inflammation, reactive hyperplasia, metastasis. The rounded shape, the loss of the hypoechoic rim and the reduction of the echogenicity of the image of the lymph node portal suggest its infiltration by tumor cells.

Ultrasound of the mammary glands has a higher sensitivity in the detection of axillary lymph nodes compared with the data of palpation, clinical evaluation and X-ray mammography. According to Madjar, palpation gives up to 30% of false negative results and the same false positive data on lymph node involvement. Echography revealed 73% of breast cancer metastases in the axillary lymph nodes, while palpation - only 32%.

[11], [12], [13], [14]