Mammary cancer. What is this disease?


The purpose of this series of articles is to help you, your family, and those close to you expand knowledge about breast cancer and understand what this disease is all about.

We hope that you will find answers to most of your questions about diagnostic methods and methods of treatment, side effects that sometimes occur during treatment, as well as about the process of recovery and recovery.

At the end of each chapter, there are questions for you to ask your caregiver. Your direct participation in the fight against the disease and in the decision-making process is necessary: ​​make sure you get all the explanations from the staff. ask questions and ask for clarifications if you do not understand all the information.

What is cancer?

The organs and tissues of the body are made up of small building blocks called cells. Although cells in different parts of the body may look and function differently, most of them go through the process of renewal in the same way, i.e. by division. As a rule, cell division occurs in an orderly but also organized manner.

If for some reason, the process gets out of control, the cells continue to divide unnecessarily and the result is a cell mass called a tumor. Tumors are classified into two types: benign and malignant (cancerous).

Breast cancer is a malignant tumor that develops in the cells of the milk ducts of the mammary gland.

Benign tumor

The cells of a benign tumor do not spread to other organs in the body, however, if they continue to develop while remaining in place, pressure can build up on nearby organs.

Cancer tumors (malignant)

This type of tumor is made up of cells that can spread. If left untreated, the tumor can invade and destroy adjacent tissues.

Sometimes, cells separate from the original (primary) tumor and spread to other organs in the body through the circulatory or lymphatic system.

Once in a new location, these cells can continue to grow and form new tumors, which are called secondary tumors, or metastases.

The final diagnosis of a benign or malignant tumor is established by analyzing a sample of suspected tissue under a microscope in a laboratory – (biopsy},

There are many types of breast cancer; some are more common while others are less common.

Breast structure

The mammary gland of a woman is located in front of the ribs and muscles of the chest and consists of glandular tissue, which consists of the mammary glands (Milk Glands or Lobules), the milk ducts (Milk Ducts) that supply milk to the nipple during breastfeeding, adipose, and connective tissue.

The muscles that cover the ribs, together with the ribs themselves, form the chest wall. The connective tissue in the mammary gland is an elastic tissue that can weaken or stretch over a woman’s life, depending on hormonal changes in her body and her weight.

The amount of adipose tissue in the mammary gland depends on the genetic data (hereditary) and the woman’s diet.

Natural changes occur in a woman’s mammary gland throughout her life – with age, during menstruation, pregnancy, and lactation, while taking birth control pills, and also during menopause. Breast size, texture, and shape may vary from woman to woman.

The breast tissue extends into the armpit (the “tail” of the breast). Behind it in the armpit is a group of lymph nodes (“glands”), the normal diameter of which is less than 1 cm.

Lymphatic fluid flows through them, draining the mammary gland (as well as in other organs). These nodes are part of the lymphatic system that is distributed throughout the body.

It helps protect the body from disease. This system maintains the balance of proteins and fluids in the cells of the body by removing residual circulatory processes.

It transports the cells of the immune system into the bloodstream, providing an effective immune response against foreign agents.

Breast cancer risk factors and high-risk populations

Most of the causes of breast cancer are still unclear, but certain risk factors can increase a woman’s risk of getting cancer.

It is important to note that a woman’s presence of one or more risk factors does not mean that a woman will develop cancer, just as the complete absence of risk factors does not mean that a woman will not develop cancer.

Gender (gender): Breast cancer is much more common in women than in men. Among men, the prevalence is less than one patient per 100 women with cancer.

According to the National Cancer Registry in Israel, 50 men are diagnosed with breast cancer every year, compared with more than 4500 women.

Age: The risk of developing cancer increases with age. According to the National Cancer Registry in Israel, breast cancer is more common in women aged 50 and over, and approximately 79% of cases are diagnosed in these age groups.

About 15% of patients are diagnosed between the ages of 40 and 49, and about 6% of patients are diagnosed with cancer before the age of 40.

Family history: Women with a family history of breast or ovarian cancer diagnosed with a close relative, especially a first-line relative (mother or sister), or women with a genetic mutation that increases the risk of cancer, are susceptible to a higher risk of developing breast cancer (see article 2 “Breast cancer and genetics”).

Medical history and breast structure: Women who have been diagnosed with breast cancer in the past, including DCIS (Ductal Carcinoma In Situ), LCIS (Lobular Carcinoma In Situ), and ADH (Atypical Ductal Hyperplasia) – non-cancerous breast conditions, or women with the dense structure of breast tissue, are at a higher risk of developing breast cancer.

The term “dense mammary gland” is applicable when most of the breast tissue consists mainly of connective tissue and very little adipose tissue. This structure is especially typical for young women.

Radiation therapy (radiotherapy) to the chest area at a young age: Patients who received radiation therapy to the chest area (usually for Hozhkin’s lymphoma), especially when the breast is developing, are at a higher risk of developing breast cancer …

Hormonal factors increase the risk of developing breast cancer:

  • Women who have been receiving hormone replacement therapy (HRT) to relieve symptoms of menopause, especially estrogen-progesterone therapy, for over 10 years. With the discontinuation of treatment, the risk decreases. These women are encouraged to be closely monitored by a physician and receive treatment for as little time as possible.
  • Women who have never given birth or have given birth at a later age (after 35 years).
  • Women who have not breastfed, or women who have breastfed for less than a year.
  • Women who started menstruating early (before age 11) and menopause came relatively late (after age 55).

Lifestyle: Scientific research shows a clear link between an increased risk of breast cancer and obesity, physical inactivity, poor diet, excessive alcohol consumption, and smoking.

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After an in-depth review of the strongest available science on the benefits and harms of screening mammography, as well as input from the public and health care professionals during the public comment period, the Task Force issued its final recommendations on breast cancer screening on January 12, 2016. You can learn more about how the Task Force’s final recommendations converge with other evidence-based guidelines in an editorial published in Annals of Internal Medicine.


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