The oncologist told how to fight breast cancer

— Tatyana Yuryevna, why is breast cancer the leader today among all female oncological pathologies?

— Breast cancer is indeed the leader in the structure of cancer incidence among women. About 2 million new cases of malignant breast tumors are registered annually in the world, including 66 thousand detected in Russia. This increase in incidence is associated, on the one hand, with the accumulation and modification in recent decades of various risk factors for breast cancer, including those affecting the frequency and nature of mutations of a number of key genes, and on the other hand, with improving the quality of early diagnosis and the introduction of mammography screening programs. Risk factors such as early onset of menstruation, late menopause, decreased number of births, late first birth, sedentary lifestyle, predominance of fatty foods in the diet, and so on, lead to disruption of hormonal balance, cell division processes and the accumulation of somatic mutations. With hereditary forms of mutations, the probability of developing breast cancer during life reaches almost 90%. At the same time, the risk of other malignant tumors, especially ovarian cancer, increases. It is important to note that the presence of risk factors does not always lead to the development of breast cancer, and their absence does not protect against tumor development.

— It is believed that breast cancer is at least two hundred different diseases. Why?

— In a woman, breast cancer is a multifaceted disease that occurs individually in each case. This is explained by the fact that estrogen, progesterone and HER2 protein receptors can be found on the surface of tumor cells. Their presence or absence in the cell determines whether the tumor belongs to one or another biological subtype. For example, hormone-sensitive cancer is characterized by the presence of estrogen and progesterone receptors on the cell surface. This indicates the potential effectiveness of hormone therapy for this type of tumor. If morphologists detect HER2 receptors, then this will be HER2-positive breast cancer, which requires targeted therapy. In the absence of all three types of receptors, we are talking about triple-negative breast cancer, which does not respond to either hormone therapy or targeted therapy, but is highly sensitive to chemotherapy. However, other factors also influence the clinical course of the tumor. For example, age is important: in young women, tumors are less sensitive to hormone therapy and are more aggressive than in older women. It also affects the course of the disease and the histological type of tumor. For some rare types, it is necessary to deviate from the recommended standard treatments. For example, the presence of BRCA gene mutations in a tumor requires the prescription of PARP inhibitors. There are other targets for which there are targeted drugs. Many other internal and external factors can influence the behavior of the tumor, but each woman truly has her own breast cancer, for which we select individual treatment. How many women, so many breast cancer. There is an expression – “for the right patient, the right treatment at the right time,” and I would also add “in the right place,” so there are a lot of factors here that indicate that as many women as there are, there are so many treatment options for the disease.

— Some oncologists say that the high survival rate for breast cancer is a myth. Is this true or not?

— If we speak in the language of statistics, then the number of patients with stages I and II of the disease is growing and already reaches approximately 70%. On the other hand, the frequency of stages III and IV decreases. In countries that have implemented screening programs at the national level and use the most modern methods of systemic treatment, against the backdrop of increasing incidence, there is a significant decrease in mortality rates. And this cannot be ignored. Although, according to forecasts, the incidence of breast cancer will increase, because we will increasingly diagnose the disease in the early stages.

— Targeted and immunotherapy are the latest promising treatment methods. Is there anything fundamentally new in this direction? What is, for example, adjuvant therapy?

— Let’s repeat once again that about 70% of breast cancer is diagnosed at stages I and II. To treat patients, we use a so-called complex of measures, including multidisciplinary, individualized and problem-oriented approaches. Of course, in the early stages, surgical treatment is still the leading method. But since breast cancer is considered a systemic disease, the importance of drug therapy is also extremely high. At the postoperative stage, taking into account various factors, including the biological subtype of the tumor, age, and risk factors for relapse, one or another volume of complex treatment is prescribed, including adjuvant (postoperative) systemic drug therapy. This can be hormone therapy, targeted therapy, or chemotherapy, including in combination with immunotherapy. Adjuvant therapy is aimed at destroying latent micrometastases that are not detected by existing radiological diagnostic methods. If we are talking about chemotherapy, then this is a medicinal method of influence based on the use of agents that act on rapidly dividing cells of the body, which include tumor cells, hair follicles, cells of the bone marrow, gastrointestinal tract and reproductive system. Chemotherapy leads to the death of tumor cells.

The next type of treatment is called “hormone therapy”. Essentially, this is a treatment aimed at blocking estrogen receptors, which prevents the stimulation of tumor growth. In addition, a new type of adjuvant therapy with so-called cyclin-dependent kinase inhibitors, that is, proteins that suppress the action of substances that cause the proliferation of cancer cells, is now being actively studied and is already being used somewhere. This treatment option allows both to increase the effectiveness of hormone therapy and to overcome resistance to hormonal treatment.

The action of targeted therapy can be compared to a key and a lock, where the lock is a specific target, and the key is the corresponding biologically directed targeted therapy, from the word target (“target”). Initially, the main focus of targeted therapy was metastatic disease. It can be prescribed either as monotherapy or in combination with chemotherapy and hormone therapy.

The first targeted drug for the treatment of breast cancer was trastozumab. Over time, a large number of targeted drugs have entered our clinical practice, which have also led to a significant improvement in the effectiveness of treatment, both in terms of increasing life expectancy and improving the quality of life of patients.

Immunotherapy is becoming increasingly important. Tumor cells form in every person throughout life. Suppressor genes, the immune system and other factors prevent the development of such cells. However, due to mutations, tumor cells escape the control of the immune system. The goal of immunotherapy is to restore this control. Immunotherapy is a method that is not so actively used in breast cancer. However, the triple-negative subtype of breast cancer is sensitive to immunotherapy. This type of therapy teaches the body’s immune system to recognize particularly aggressive types of tumors.

— How will the cessation of clinical trials of new oncology drugs in our country (those for which research has not been started) affect Russian patients with breast cancer?

“It is important to note that the possibility of receiving drug therapy in clinical trials has been and remains an important option, because we also have domestic drugs that are widely studied in clinical trials. In general, of course, our Russian women, thanks to their participation in clinical trials, could receive effective treatment long before the drug was registered in the Russian Federation. But we are currently conducting extensive research on domestic drugs, so to say that we currently have no research at all is also wrong.

— What are the main ways to prevent breast cancer?

— The main way to prevent breast cancer is a healthy lifestyle in its broad sense. The first, I would say, the cornerstone, is nutrition. It must be balanced. The daily diet should include vegetables and fruits, up to approximately 400 g/day. It is also recommended to minimize the consumption of foods with hydrogenated fats, because they are harmful to the body. It is important to include foods with mono- and polyunsaturated fatty acids in your diet, for example, fatty fish once or twice a week, vegetable oils. From canned fish, it is better to choose tuna, mackerel, and anchovies. The Mediterranean diet is best when it combines meat with vegetables and fruits.

Second: active physical activity. It is also important to strive for normal body weight, because an increased amount of fat fiber due to increased nutrition is a source of estrogen synthesis.

The famous Russian obstetrician-gynecologist Leila Vladimirovna Adamyan called this formula: 20–40. That is, at the age of 20, a woman should give birth to a child, and at 40, become a grandmother. Of course, it is important to give birth to children while being healthy, because all the factors that affect the body are reflected in the egg. The older the woman, the more factors that negatively affect the egg.

Therefore, it turns out: a healthy lifestyle, active physical activity, a healthy diet, optimal body weight, implementation of reproductive function at 20 years old, breastfeeding for a year or more and, most importantly, heredity. You need to remember this and undergo medical examination. And starting from the age of 40, you need to have a mammogram every 2 years.

— Please give basic advice to women on early diagnosis!

— The most important thing in any business is awareness. Including risk factors and ways to modify these factors, i.e. eliminating them or reducing their negative impact. You need to try to undergo timely medical examination, including mammography, master self-examination skills, lead a healthy lifestyle, and be especially actively examined if you have a family history. All this will allow us to identify the disease at an early stage, and maybe even prevent its development.