Cancer is a group of diseases characterized by abnormal cell growth. It is the leading cause of death across the globe. In 2008, more than 7 million people, which is nearly 13% of all deaths, died because of different types of cancer (“Cancer”). Breast cancer also contributed to this rate and took about 450 000 lives, which make this type of cancer one of the most worldwide. So, what causes breast cancer and what are the symptoms? How can be this disease treated and prevented?
Breast cancer is a type of cancer that starts in the breast cells. Usually it is a female disease, though it happens to occur in male as well. The two most common types of breast cancer are ductal and lobular carcinoma. Ductal carcinoma is the one that develops from the ducts, through which milk comes from the breast to the nipple. Lobular carcinoma is the one that develops from the breast tissue that produces milk (lobule). Ductal carcinoma is the most frequent to occur. Very seldom breast cancer starts in the other breast areas.
Breast cancer can be invasive or noninvasive. If the cancer is invasive, it spreads from the lobules or ducts to other nearby areas of the breast. If it is noninvasive, it does not spread to other tissues. When the abnormal cells reach the lymph nodes, they can be transmitted to the other organs (lungs, liver etc.) and other parts of the body. There is a high risk for the noninvasive cancer to turn into invasive one if it is not treated. Generally, breast cancer is the most invasive type of cancer.
Some types of breast cancer are negatively influenced by estrogen, main sex hormone in females. In other words, estrogen provokes breast cancer cells to grow, since such cells have estrogen receptors on their surface. Such type of cancer is called ER-positive cancer. Also, some women are prone to cancer, while they have HER2, a gene that promotes cancer cell grow and develop. The disease in this case declares itself more severely and the risk that it will recur is much higher than after regular cancer. Accordingly, such type of cancer is called HER2-positive breast cancer (“Breast Cancer”).
The reasons for breast cancer are many. Some of them cannot be influenced or changed, some of them can. Those that cannot be changed include:
- Aging – the older a person is, the higher is the risk of getting breast cancer. Usually cancer is discovered in women after age 50.
- Gender – women suffer from breast cancer 100 times more often than men.
- Genes – some genes may provoke the growth of cancer cells. For example, people who have BRCA1 and BRCA2 genes have much higher risk of developing breast cancer. Another dangerous gene is TP53. Moreover, these genes may be inherited, even though the majority of breast cancers are not heritable. Also, those who have a close relative with breast or ovarian cancer may have the higher risk of breast cancer.
- Relapse – if a person has had breast cancer, even noninvasive one, before, there is a higher risk for her or him to develop the cancer again. Alike, those who have suffered from some kinds of benign breast lumps are predisposed to breast cancer.
- Menstrual cycle – women who have had early periods (before age 12) or late menopause (after age 55) are more likely to develop breast cancer, because their bodies produce estrogen for longer period. Also, obesity connected with entering menopause may higher the risk of the disease development, since body of overweight woman produces more estrogen.
- Dense breast tissue – women who have denser breast tissue are predisposed to breast cancer.
- Height – specialists suggest that tall women suffer from breast cancer more often than average or short women.
The reasons for breast cancer that cannot be changed include:
- Alcohol abuse – the more people drink alcohol, the greater are chances of developing the disease.
- Childbirth – women who have never born or who did after age 30 have an increased risk for the disease. The more children a woman has, the lower is the risk. If a woman becomes pregnant at an early age, it may reduce the risk as well.
- Radiation – undergoing X-rays may slightly enhance the risk of developing breast cancer. Also, if a person was exposed in the childhood to radiation treatment of cancer of chest area, he or she is more vulnerable to development of the disease.
- Hormone Replacement Therapy (HRT) – those who underwent hormone replacement therapy with estrogen for more than one year have greater chances of getting breast cancer.
- Wrong jobs – some scientists believe that certain jobs may provoke breast cancer development. Such jobs are connected with agriculture, metal industry, plastic manufacturing etc. Other scientists prove that working at night prior to the first pregnancy can have negative impact on women and their vulnerability to this disease too.
At the early stage there are no particular symptoms that could indicate that the disease starts. That is why it is so important to go through regular breast examinations. At the later stages a patient may observe the following symptoms: lumps, swellings and thickenings in the breast or armpit, which usually does not hurt; change in skin color or texture; change in the size and shape of breast or nipple like dimpling; bloody, clear or yellow liquid coming from the nipple (“What Is Breast Cancer? What Causes Breast Cancer?”). The symptoms in men are usually lumps, swellings, breast pain tenderness and skin ulcer.
If some of the above mentioned symptoms are detected, a person should consult a doctor right away. Firstly, a doctor will perform a physical exam of breasts, armpits, chest and neck. If he notes something suspicious, some of the more serious diagnostic tests may be necessary. X-ray (mammography) is used to screen breast cancer or any lumps. Breast ultrasound helps to understand if the lump is solid or fluid-filled. Biopsy is used to surgically remove some of the lump tissue for the further examination. Breast MRI helps to identify the breast lump. CT scan, PET scan and lymph node biopsy help to see if the cancer has spread. If such tests show that a person has cancer, more tests called staging are to be done. These tests identify the stage of the cancer (it may range from 0 to IV) and help doctors to choose particular treatment.
If the breast cancer is diagnosed, the doctors may opt for one of the following treatments: chemotherapy, hormone therapy, radiation therapy, surgery or biological therapy (targeted drug therapy). Chemotherapy is used to kill cancer cells and sometimes to stop estrogen production. This type of therapy has numerous side effects such as nausea, vomiting, hair loss etc. Hormone therapy is used to block particular hormones the cancer is sensitive to (for patients with ER-positive breast cancer). It is normally used after surgery. The main medications of this type are: tamoxifen, aromatase inhibitors, and ovarian ablation. Radiotherapy is usually used to destroy cancerous cells in the breast that are left after surgery or chemotherapy. Radiation therapy may vary depending on a type of cancer: breast radiation therapy, chest wall radiation therapy, breast boost, lymph nodes radiation therapy or breast brachytherapy may be chosen. Fatigue and irritation of the breast skin are possible side effects of the therapy. Surgery may include lumpectomy (if the tumor is not big), mastectomy (removing the breast completely), breast reconstruction surgery. Biological therapy is a relatively new kind of cancer treatment. It involves the use of special anticancer drugs, aimed usually at the HER2 protein. Biotherapy may include taking such medicine as Trastuzumab (Herceptin), Lapatinib (Tykerb) and Bevacizumab (Avastin). Application of this therapy may be followed by various side effects (skin rashes, heart damage, headaches etc.).
Scientists are not completely sure if a certain lifestyle can promote or prevent breast cancer. Nevertheless, they have some recommendations. People should reduce the amount of alcohol they drink (no more than one alcohol drink per day) or quit drinking at all. Some say that well-balanced diet may reduce the risk of developing breast cancer. Anyway, looking after one’s weight is very important. Most of the scientists agree on the fact that physical exercising is helpful in preventing the disease. Postmenopausal hormone therapy and drugs blocking estrogen may sometimes be considered as well. People, especially women should regularly have their breast checked. One more important tip is to give birth and to feed babies with the breast, since it lowers the chances of developing breast cancer.
In conclusion, breast cancer is one of the most widespread types of cancer. Women have much higher risk of developing the disease than men do. Usually it starts in breast ducts. The reasons for breast cancer may include aging, genes, recurrence, anatomical peculiarities and some secondary factors. When detected, breast cancer can be treated with a range of therapies. Nevertheless, prophylactic measures should be taken into consideration.