Breast cancer

Oncology |
Breast cancer (1)

Breast cancer

Istituto Gentili is involved in the treatment of advanced breast cancer and in improving the quality of life of patients, characterized by specific clinical needs.

Breast cancer is the most common malignant neoplasm in the female population. In Italy, approximately 55,000 new diagnoses are expected in 2020, which represent approximately 30% of all female cancers. In women it is the first cause of cancer death. There are 834,200 women living in Italy after a diagnosis of breast cancer. About 37,000 women live with its most aggressive form (metastatic breast cancer). It is estimated that 6-7% of breast cancer cases are already metastatic at diagnosis.

Istituto Gentili is involved in the treatment of advanced breast cancer and in improving the quality of life of patients, characterized by specific clinical needs. At this stage of the disease, treatment becomes an important component of everyday life, with the goal of long-term control of the disease with the lowest incidence of side effects.

Characteristics

Breast cancer is caused by the uncontrolled proliferation of some altered cells of the mammary gland which, due to multiple genetic mutations, become able to detach themselves from the tissue that generated them (primary tumor) to invade the surrounding tissues and, with time, also more distant organs (metastases).

Breast cancer is a heterogeneous disease, which can assume different clinical and biological profiles depending on the type of cells altered as a tumour, the size of the tumour mass and the presence of some tumour markers, such as hormone receptors (estrogen and progestin) and the receptor for the human epidermal growth factor (HER2).

The main tumour subtypes are:

intraepithelial ductal neoplasm, which affects the cells of the ducts;
intraepithelial lobular neoplasm, which affects the lobule cells.

Depending on the ability of the altered cells to invade other tissues (for example, bone and liver), tumours can be classified as invasive or infiltrating, more dangerous and aggressive.

The prevailing classes are:

invasive ductal carcinoma;
invasive lobular carcinoma.

Based on the presence or absence of biological markers, breast tumours are divided into:

positive HER2 +
negative HER2-

About 75% of breast cancers are positive for the estrogen receptor (ER +), while one fifth is characterized by a high presence of the HER2 receptor, which makes them particularly aggressive (HER2 +). There are also breast cancers that do not express either hormone or HER2 receptors: in this case, we speak of a "triple negative" tumour.

The state of positivity or not to the biological markers is fundamental both to plan the most suitable cancer therapy for the single patient with breast cancer and to evaluate the prognosis (times and characteristics of evolution of the disease and survival).

Symptoms

Breast cancer does not always give symptoms easily recognizable at an early stage. The most common is the onset of a nodule with irregular contours, palpable in the context of the mammary gland and generally not associated with pain.

Other frequent symptoms are swelling of one part or the whole breast, the appearance of orange peel skin, changes in the shape of the breast (for example, bumps), alterations in the shape of the nipple, loss of fluid or blood from the nipple, swelling of axillary lymph nodes, around the clavicle or neck.

In all the cases in which one or more of these symptoms are found, it is necessary to consult the family doctor for a first evaluation, the possible prescription of clinical and instrumental examinations for further study and / or the prescription of a breast examination.

The stages of the disease

After diagnosing breast cancer, its staging is essential.
It involves the evaluation of:

Size of the original tumour

Extension of the tumour to the lymph nodes

Presence or absence of metastases

(portions of tumours disseminated in other organs)

All this information is essential because it allows the doctor to better understand the characteristics of the tumour and to evaluate the choice of the most appropriate treatment for each patient.

The evolution of breast cancer is divided into 5 stages.

Stage 0: carcinomas in situ, ductal or lobular.

Stage 1: early-stage tumours, less than 2 centimetres in size; in this stage, the tumour cells have passed the walls of the galactophore ducts or the lobules from which they originated, without however spreading to the lymph nodes or other parts of the body.

Stage 2: tumours at a more advanced stage; their dimension can range from 2 to over 5 centimetres without involving the lymph nodes or they could be smaller, but they have already reached the axillary lymph nodes.

Stage 3: locally advanced tumours; regardless of size, they are tumours already extended to the lymph nodes or the areas closer to the breast (skin, chest wall under the breast, etc.).

Stage 4: metastatic tumours spread to other organs. Bones, liver and lungs are the most frequently affected sites, but spinal cord or brain can also be affected (especially in women with HER2 +, triple negative and BRCA + breast cancer).

To date, in most patients who have metastases it is not possible to permanently eliminate the disease. However, thanks to appropriate and well conducted treatments, it is possible to guarantee a good quality of life and prolonged survival.

Risk factors

Most breast cancers are caused by non-hereditary factors, that is to say related to unfavourable lifestyles or the environment (modifiable risk factors). Only a small proportion, between 5 and 10%, is linked to genetic predisposition (a non-modifiable risk factor).

1. Modifiable risk factors:

overweight / obesity: they increase the probability of developing a hormone-positive breast cancer;
alcohol intake: increases the risk of breast cancer and relapses in women who have already suffered from cancer or benign breast disease;
smoking: it increases the risk of breast cancer by about 25%, which is the higher the earlier the person started smoking;
excessive amounts of fat in the diet: they increase the risk of developing breast cancer.

Diet plays a key role in determining the propensity to develop breast cancer, but it can also be exploited for its prevention. In particular, it has been observed that there are foods capable of performing a protective action, such as:

foods containing phytoestrogens (plant hormones similar to female estrogens), such as soy and derivatives, algae, flax seeds, cabbage, legumes, berries and whole grains;
vegetables of the cruciferae family (turnips, mustard, rocket, cauliflower, Brussels sprouts, radishes, cabbage);
vegetable fibres in general;
fish (a source of animal protein to be preferred over meat and cheese).

Pregnancy and breastfeeding are also protective factors. In particular, it has been estimated that having at least one child decreases the risk of breast cancer by about 30% compared to not having, since pregnancy reduces the exposure of breast cells to estrogen hormones.
Breastfeeding for long periods, on the other hand, reduces the risk of breast cancer by 4% every 12 months of breastfeeding.

In this case, the protective effect is linked to:

healthier lifestyle that women follow during breastfeeding: balanced diet, reduced alcohol consumption and smoking cessation;
lower number of menstrual cycles, resulting in less exposure to fluctuations in sex hormones;
more complete maturation of the cells of the mammary glands which makes them more resistant to possible neoplastic transformations.

2. Non-changeable risk factors

age: the chances of getting breast cancer grow with increasing age; more than 75% of breast cancer cases involve women over 50;
familiarity: women with mothers or sisters who have developed breast cancer have a greater risk of falling ill; about 5-7% of women with breast cancer have more than one first-degree family member who has had the disease (especially in juvenile cases);
genetics: some genes predispose to the development of breast cancer; for example, mutations in the BRCA1 and BRCA2 genes are responsible for about 50% of the inherited forms of breast and ovarian cancer;
personal history of breast cancer: women who have already suffered from this disease are about 3-4 times more likely to develop a new tumour in the other breast; however, this is a limited risk.

It is not possible to intervene on non-modifiable risk factors to reduce the probability of becoming ill. However, it is possible to mitigate the impact of the disease through early diagnosis.

Screening and early diagnosis

The possibility of recovery from breast cancer is greater the earlier the diagnosis. Although most cancers affect women over 40, breast cancer prevention should start as early as age 20. The simplest means of early diagnosis is breast self-examination, performed monthly. Furthermore, it is advisable to carry out annual breast checks by a gynaecologist or breast specialist. After the age of 45-50, mammography or ultrasound examination of the breast is recommended every two years (which can also be performed in younger women in the presence of familiarity or specific predisposition).

Self-examination

It can be done comfortably at home because, knowing the appearance and usual consistency of the breast, the woman can pick up any change early.
It is a useful exam for finding nodules in the mammary gland, but also to keep under control retractions or changes in the skin, fluid leaks from the nipples and mutations in the shape of the breast: all signs that must encourage consultation with the trusted gynaecologist.
From the age of 20, the exam can be taken once a month, between the 7th and the 14th day of the menstrual cycle: respecting this timing is important to avoid "false alarms" because the structure of the breast changes on the basis of monthly hormonal fluctuations.

Breast examination, ultrasound

From the age of 45-50 (even earlier in the case of familiarity or alterations), home self-examination must be accompanied by breast examinations and more precise instrumental examinations such as ultrasound, mammography or MRI.
Between the ages of 20 and 40, an annual visit by the gynaecologist or senologist is sufficient; in case of familiarity or finding of nodules, it is possible to deepen the evaluation with an ultrasound and a biopsy (needle aspiration) of the suspicious nodule.
In the absence of other indications from the specialist, between 40 and 50 years, women with familiar breast cancer should begin to undergo mammography, preferably associated with ultrasound.
Between the ages of 50 and 69, the risk of developing breast cancer increases: consequently, it is recommended to undergo a mammography check every 2 years. The execution of magnetic resonance imaging is instead needed by women with "very dense" breasts (difficult to assess with other methods), in doubtful cases or to plan surgery.

Genetic tests

They are useful for finding genetic markers that increase the risk and / or worsen the prognosis of breast cancer, such as mutations in the BRCA1 and BRCA2 genes, responsible for some inherited forms of breast and ovarian cancer.
The genetic test for the evaluation of BRCA1 and BRCA2 involves a simple blood sample.

Treatment

The type of treatment of breast cancer is chosen on a case-by-case basis, taking into account the stage of evolution of the disease, but also the age of the woman and her possible desire to have children after recovery.

The treatment options for breast cancer include:

surgery;
radiotherapy;
chemotherapy;
hormone therapy;
biological therapies.

REFERENCES

Italian Association of Medical Oncology (AIOM), Italian Association of Cancer Registers (AIRTUM). Cancer numbers in Italy 2020
Guidelines for breast neoplasia. Edition 2020
Cappelletti P. Precision Medicine and Laboratory Medicine. Italian Review of Laboratory Medicine 2016; 12: 129–133
Viale G. The current state of breast cancer classification Annals of Oncology 2012;23(Suppl 10): x207–x210
Lee K. The Impact of Obesity on Breast Cancer Diagnosis and Treatment Current Oncology Reports 2019;21:41