The importance of breast cancer lies in its overwhelming statistics in women, with approximately 1.6 million cases annually, far surpassing the 1% of cases in men.
Early detection and diagnosis of breast cancer allows for timely control and treatment.
With the possibility of complete eradication, we will emphasize diagnostic methods that are available to patients.
Let’s start by defining cancer.
It is the abnormal growth of cells that reaches the point of forming a tumor, in this case, in the breast.
We can divide this cancer into 2 types, non-invasive breast cancer (invasive ductal carcinoma – main excretory ducts, nipple and areola) and invasive breast cancer (invasive lobular carcinoma – lobules of excretory ducts).
The former refers to the pre-malignant development of cancerous cells in the mammary ducts without becoming cancerous and which can progress to its invasive variation.
The latter is attributed to the spread of cancer outside the mammary ducts to the mammary lobules.
What are the risk factors?
There are diverse factors that promote the development of carcinoma, and the forms in which they present can be non-modifiable or modifiable.
- Non-modifiable: The predominant factor is attributed to the female gender, which is exponentially higher than the male gender.
- As well as age, as the incidence from age 65 is approximately 45-65 cases per 100,000.
- In addition, due to a history of breast carcinoma in close relatives of the patient or genetic derivations associated with microdeletion of chromosome 17q21.
- Being nulliparous, that is, not having had children or having pregnancies after age 30.
- Modifiable: Obesity associated with breast cancer is established with a body mass index (BMI) above 30, which is more important in postmenopausal women.
- A balanced diet and reduction in carbohydrates can reduce abnormal levels of estrogen. Early menarche, before age 11, and late menopause, after age 55, cause prolonged exposure to estrogen over the course of life.
- Alcoholism and smoking are associated with the development of multiple diseases and also increase the risk of breast cancer.
What are the protective factors?
Breastfeeding is considered the most important protective factor, along with pregnancy before the age of 30, and even before the age of 24, which has greater benefits for the prevention of breast cancer. Medications such as raloxifene, used for osteoporosis treatment during menopause, and tamoxifen, used in advanced stages of breast cancer and hormone therapies, both block estrogen activity, reducing the risk of breast cancer and controlling the condition in patients who already have it.
The importance of early detection.
From the age of 25, self-examination or examination in a medical center should be routine. Knowing the morphology of your body and in this case of the breast, will help detect visible changes or palpable lumps of medical importance, as this is the simplest and most important diagnosis.
Imaging diagnosis of breast cancer.
The accurate detection of breast carcinoma is based on radiological and ultrasound images, and in some cases even magnetic resonance imaging. These tests are recommended annually from the age of 40 and 5 years after the onset of menopause, after which an imaging examination is recommended every 2 years.
In non-advanced cancer, detection of tumors through palpation is not the most accurate. However, it should still be performed, but for confirmatory purposes, imaging diagnoses are used. The routine imaging study is the mammogram, which despite being the method of choice, is not the most sensitive or specific. For this reason, implementing one test often requires complementing it with another, in order to confirm the development or absence of breast cancer.
Below are the imaging modalities used for breast cancer detection.
Used as a method of early detection for breast symptoms and routine evaluation, even in asymptomatic patients, it uses low-dose ionizing radiation. The projections used cover the entire breast radius, including craniocaudal projections, which identify distortions or inflamed nodules, recommending compression to magnify the distortions found, and the medio-lateral oblique projection, which is attributed to the real identification of a tumor and visualization of lobular calcifications.
Complementary physical examination and ultrasound provide support in the diagnosis of women who have a large amount of fibro-glandular tissue in their breasts (dense breasts), which is normal in women under 40 years old and pregnant women but less common in those over 50 years old. Between 5 and 7 cases are detected per 1,000 exposed by mammography.
In your sensitivity, meaning the efficiency of the exam to detect findings of a disease, varies from 60% to 95%, and specificity, determined by the accuracy of the exam in the presence of the disease, ranges from 80% to 90%. Both values increase with age.
Tomosynthesis – 3D mammography.
It is an advanced mammography with a function similar to a tomography, creating millimeter-thin sections for visualization of cancer whether it is invasive or not.
It is a method that provides better results than conventional mammography based on imaging from the necessary angles that together create the three-dimensional image, beneficial as both an early detection method and better exposure of the breasts, even if they are dense.
The cases presented through this diagnosis range from 7 to 10 per thousand.
Digital mammography with contrast enhancement.
It uses conventional mammography in conjunction with X-ray support and intravenously administered iodinated contrast.
This enhances the mammary area by detailing its morphology, which facilitates the detection of non-palpable tumors that cannot be properly visualized in the initial mammographic study.
Unfortunately, there is not enough evidence to support its proper performance.
Medical examination through US is useful for a patient where, by means of mammography, dense breasts are observed, which makes it difficult to visualize the mammary area completely and, therefore, the diagnosis of a possible cancer.
However, ultrasound allows for adequate observation of this area in the presence of a large amount of tissue, differentiating abnormalities and confirming the presence of tumors, as well as their development, whether early or advanced, and allowing for the identification of abnormal lymph nodes in the axillary area, which frequently accompany breast cancer.
This exam confirms between 8 and 12 cases per 1,000 ultrasounds performed when no abnormalities are initially found in the mammography.
The search principles in this method are related to the appearance of new blood vessels in the studied breast (neovascularization), which is an important pattern in any cancer since they generate their own blood supply, and through this method, the malignant tumor can be found.
To improve the exam results, microbubble contrasts can be administered, allowing for greater enhancement of tiny vessels.
The exam has a sensitivity of 95%, as all the vascularity of the mammary area is contrasted; however, due to the difficulty of finding the blood vessels formed by the tumor itself, it has a specificity of 79%.
Magnetic resonance imaging (MRI)
This type of study uses electromagnetic pulses to form highly detailed images of breast tissue, without the need for ionizing radiation.
Its use is recommended for patients with dense breasts, women with a family history of breast cancer or with hereditary genetic factors such as mutations in the BRCA1 or BRCA2 genes.
It is also recommended for patients with breast implants or women who have received radiation therapy in the chest area before the age of 30.
This method can be accompanied by a biopsy, where part of the breast tissue is removed for further study and diagnosis, in order to detect the development of tumor cells.
Molecular breast imaging by images
It is associated as a complementary test to the aforementioned ones.
The duration of this test is around 40 minutes and is performed similarly to a mammogram. Although it is recognized as an acceptable test, the contrast material used (Technetium-99mTc) is highly radioactive.
It has an approximate value of 2.5 mSv at its lowest dose, equivalent to the radiation that the human body is exposed to over 8 to 12 months.
Its recent implementation has given good results consistent with diagnoses, confirming between 13 to 15 cases per thousand studies.
Positron emission tomography (PET)
The use of PET with the implementation of radiotracers is related to advanced stages of breast cancer, once metastasis occurs in different organs of the body.
It allows for the creation of 3D images from different angles.
This test takes 1 hour to detail images that can confirm the presence of possible spread of cancer to other areas.
It is not recommended as the first choice method due to the high probability of no detection of early stages of cancer (small tumors).
At Grupo PACS and Teleradiología de México, we are committed to timely detection of this important health problem, both in Mexico and the rest of Latin America. Our cloud-based image storage and radiological reporting system facilitate interpretation and follow-up of detection studies performed on patients, even when they are conducted in remote and difficult-to-access areas, as well as their integration into an electronic record, which improves the quality of healthcare for women. Additionally, we have highly specialized breast imaging doctors certified by the Mexican Board of Radiology and Imaging.