Mammography

Synonyms in a broader sense

Digital mammography, magnetic resonance mammography, galactography, mammography screening

Introduction

Mammography is a so-called imaging procedure. Usually an X-ray image of the breast is taken in two planes (from two different directions). For this purpose, each breast is squeezed one after the other between two Plexiglas plates for a few seconds.

The compression ensures that the tissue is spread out and can be better assessed because less tissue is superimposed. The examination is performed in a standing position. The result of the mammography is assessed using the BI-RADS classification (Breast Imaging Reposting and Data System): Stage I: No findings Stage II: Findings that are certainly benign (e.g. cysts in the breast) Stage III: Findings that are probably benign; a control is required Stage IV: Findings that are probably malignant; a biopsy (= tissue sample) is required Stage V: Strongly suspicious findings, a biopsy is required Stage 0: Diagnosis not feasible

Accuracy of mammography

Mammography has a sensitivity of 85-90%. Sensitivity is the sensitivity of a test to a disease. In other words, it describes the quality of a test to recognize sick people as sick.

A sensitivity of 85-90% means that 10-15% of patients with breast cancer are not detected by this method. Mammography therefore has a relatively good sensitivity. However, it is relatively unspecific.

The specificity indicates the number of correctly negative results of a method, i.e. how many healthy people are correctly recognized as healthy. Fibroadenomas (benign breast tumors), cysts in the breast or calcifications can, under certain circumstances, look like breast cancer in mammography. Therefore, if the findings are questionable, a control examination should always be carried out after some time or a tissue sample examination (biopsy) should be performed.

Radiation exposure

Like any X-ray examination (x-ray), mammography also leads to exposure of the body to radiation. Due to the special technique used, these exposure levels are even higher in mammography than in X-rays of the bones. The breast tissue (female breast) is particularly sensitive to this type of radiation at a young age.

Women under 20 years of age should therefore not undergo mammography. In women between the ages of 20 and 35, the risk should be weighed very carefully and other diagnostic methods should be used if necessary. In addition, for women under the age of 40 to 50, screening mammography (see explanation below) does not offer any advantage according to the current state of knowledge, since the younger a woman is, the higher the proportion of false positive findings. This can be explained, among other things, by the higher tissue density of the breasts of younger women (which also complicates the general assessment of the X-ray image). Thus, benign changes are not detected and an actually unnecessary and painful biopsy is performed, not to mention the psychological stress in the time until the negative biopsy result (negative means: no cancer).