What is Breast Cancer?
Breast cancer is the malignant tumor (a tumor with the potential to invade other tissues or spread to other parts of the body) that starts in the cells of the breast. It occurs both in men and women. However male breast cancer is rare [1,2].
Among Indian women, breast cancer is the commonest cancer overall [3,4].
The information given here is for female breast cancers.
Epidemiology
In 2012, 1,44,937 new cases and 70,218 deaths were reported for breast cancer in India [5].
In India, 1 out of every 2 women diagnosed with breast cancer dies of this disease, mainly because the tumor is diagnosed too late .[5]
Breast Anatomy [6]
A woman’s breasts contain specialized glands (lobules) that can produce milk. The milk producing structure of the breast consists of 15-20 lobes. Each lobe is made up of many smaller lobules which have groups of tiny glands that can produce milk. The milk travels through a network of tiny tubes (ducts) to a reservoir that lies just below the nipple. The dark round area of skin surrounding the nipple is called the areola. The breast also contains blood & lymph vessels and lymph nodes.
The Lymph System of the Breast
One of the main ways breast cancer spreads is through the lymphatic system. Lymph vessels carry a clear fluid called lymph which drains into lymph nodes. Lymph nodes are small bean-shaped structures which contain cells that fight infections (immune system cells). Lymph vessels from the breast drain into
- Lymph nodes around the collar bone (supraclavicular and infraclavicular lymph nodes).
- Lymph nodes under the arm (axillary nodes).
- Lymph nodes inside the chest near the breast bone (internal mammary lymph nodes).
A risk factor for breast cancer is anything that increases your chance of getting breast cancer.
Having a risk factor does not mean that you will definitely develop breast cancer.
Risk factors you cannot change (“non-modifiable”) [7]
- Gender: Women are more likely to develop breast cancer than men. This may be due to more exposure to hormones which promote breast cell growth (such as estrogen and progesterone).
- Age: Your risk of breast cancer increases as you age. A study in North India reported that the average age of the patient at presentation was between 45 and 50 years.
- Family history of cancer: Your risk of breast cancer increases, if your mother, sister or daughter was diagnosed with breast cancer, particularly at a young age. Your risk also increases if your father or brother had breast cancer. However, the majority of people with breast cancer have no family history [8]. Read More
- Genetic Factors: If you have inherited certain rare gene mutations from parents, you are at an increased risk for breast cancer. The most common known gene mutations observed in people with breast cancers are in the BRCA1 and BRCA2 genes. Having these mutated genes does not necessarily mean that you will get breast cancer.
Breast cancers linked to BRCA1 and BRCA2 mutations occur more frequently in younger women and more often affect both breasts compared to cancers that are not linked to these mutations. Women with these inherited mutations also have an increased risk for developing ovarian cancers. Genetic tests are available to look for these mutant genes that are linked with breast cancer. Genetic tests are not recommended for everyone. You should discuss with your doctor if these genetic tests are helpful in your case.
- Menstrual History:Having your first period at a younger age (before age 12) increases your risk of breast cancer. Likewise attaining menopause at an older age increases your risk [9].
- Past history of breast cancer: If you have had breast cancer in one breast earlier, you have an increased risk of developing cancer in the other breast.
Risk factors you can modify (life style related)
- Obesity: Being obese increases your risk of breast cancer [10]. Read More
- Pregnancy : Women who have never been pregnant have a greater risk of breast cancer than women who have had one or more pregnancies. Also, giving birth to a child after the age 35 may increase the risk of breast cancer compared to women who give birth earlier [11].
- Lactation: Lack of or shorter duration of lactation increases the risk of breast cancer [12].
- Drinking alcohol: Drinking excessive alcohol increases the risk of breast cancer.
- Hormone intake: Women treated to get relief from menopausal symptoms with combined estrogen and progesterone hormone therapy medications (hormone replacement therapy) have an increased risk of breast cancer [13]. The risk decreases when women stop taking these medications.
- Radiation exposure: Moderate to high-doses of exposure to ionizing radiation exposure or receiving radiation treatment to your chest area as a child or young adult, increases the risk of breast cancer.
Breast Cancer Signs and Symptoms
- The most common symptom of breast cancer is a new mass or lump in the breast. If you have a hard mass with irregular edges, it is more likely to be cancerous [14,15]
- Any change in the breast or nipple appearance [16,17]
- Unexplained change in shape or size of the breast
- Unexplained shrinkage of breast
- Unexplained swelling of the breast, especially on one side only
- Recent unevenness of the breasts (It is normal for women to have one breast slightly smaller than the other, but if this asymmetry is a recent one, then consult your doctor)
- Dimpling anywhere on the breast
- Sunken or inverted nipple
- Redness or scaling of the skin of the breast, nipple or areola
- Uneven areas or pores on the skin that resemble an orange peel.
- Clear or bloody discharge other than breast milk [18]
- Swelling of lymph nodes
The spread of breast cancer to lymph nodes may cause a lump or swelling under the arm or around the collar bone. You can check for these signs of breast cancer by examining your own breast every month. If you find anything abnormal, consult your doctor and get yourself clinically examined [19].
Breast Cancer Diagnosis [20]
- Physical Examination: a doctor examines your breasts and under arm tissues for any lumps by palpation. Nipples are examined for any suspected discharge, skin changes and retraction.
- Imaging Tests
- Mammogram: A mammography machine uses low-dose x-rays to take images of your breast. First the machine compresses each breast and takes x-ray images on film. This is commonly used for early detection of breast cancer.
- Digital mammogram: A mammogram that stores the electronic images of each breast in a digital, computer-readable format. This is different than a standard film mammogram, where the images are created directly on film.
- Diagnostic mammogram: Additional mammogram views beyond those done in a routine mammogram may sometimes be necessary to evaluate an abnormal mammogram or a breast abnormality.
- Breast Ultrasound: In this procedure, a device sends high frequency sound waves through your breast. The sound signals received from tissues are converted into pictures on computer screen. These images allow the doctor to look for any abnormality. Breast ultrasound can differentiate whether a lump is a cyst (filled with fluid) or solid tissue.
- MRI Scan: In this procedure, a high-powered magnet and a computer is used to scan and to create detailed images of the breast and surrounding organs. Breast MRIs are recommended only in specific cases where mammogram information is insufficient.
- Mammogram: A mammography machine uses low-dose x-rays to take images of your breast. First the machine compresses each breast and takes x-ray images on film. This is commonly used for early detection of breast cancer.
- Biopsy:
- Fine needle aspiration biopsy/cytology (FNAB/FNAC): After a positive physical examination or mammogram, a small piece of tissue/fluid is taken from an abnormal looking area of the breast and examined for cancer cells using a thin needle and a syringe without using anesthesia.
- Core needle breast biopsy: A larger, hollow needle is inserted into the breast lump and cylindrical piece of breast tissue (core) is taken out for histopathological examination to confirm cancer. A core biopsy provides more breast tissue for examination than FNA.
- Stereotactic breast biopsy: Doctor uses computerized pictures to reach the exact location of the abnormal breast tissue (guided biopsy) to remove a piece of breast tissue for examination. This is performed under local anesthesia.
- Surgical (open) biopsy: Occasionally, surgery may be recommended to take out a part or whole breast lump to check for cancer. This is performed under anesthesia.
- Nipple discharge cytology (nipple discharge exam): A sample of fluid or discharge from the nipple is examined under the microscope to look for cancer cells. Even if the nipple discharge cytology result is negative, the surgeon may go in for other tests if there is a clinical suspicion.
Early Detection [21,22]
- Clinical breast examination (CBE)
CBE is recommended for all women once a year after 30 years of age.
A clinical breast exam (CBE) is an examination of your breasts by a health professional such as a doctor, a nurse or medical social worker.
The health professional will first look carefully at your breasts for abnormalities/changes in the nipple, skin, size or shape of the breasts.
Then, using his or her fingers, the examiner will feel (palpate) your breasts for the presence of any lumps. S/he will also examine the area under both arms for any swelling of your lymph nodes.
You should have a clear knowledge of how your breasts look normally. Feel your breasts and seek medical advice promptly if any change in the breast is noticed.
BSE is a suggested option for women above age 20 years to look for early signs of breast cancer.
There are Five Steps of Breast Self-Exam (BSE).
Step 1
Stand in front of the mirror with your shoulders straight and your arms on your hips and look at your breasts (breast awareness) and check
- are they their usual size, shape, and colour
- that they are evenly shaped without visible distortion or swelling
Consult doctor if there is :- dimpling, puckering, or bulging of the skin
- changed position or an inverted nipple (pushed inward instead of sticking out)
- redness, rash, or swelling of the breasts
Step 2
- Now, raise your arms and look for the same changes.
- Look for any dimpling of skin or in-drawing nipple.
Step 3
- While you’re at the mirror, gently squeeze each nipple between your finger and thumb
- Consult doctor if nipple discharge is milky or yellow fluid or blood.
Step 4
- Lie down and use your right hand to feel your left breast and then your left hand to feel your right breast.
- Use a firm, smooth touch with the pad of your 3 middle fingers, keeping the fingers flat and together.
- Cover your entire breast from top to bottom, side to side; from your collarbone to the top of your abdomen and from your armpit to your cleavage.
- Be sure to feel all the breast tissue.
- Follow a pattern to be sure that you cover the whole breast. Begin at the nipple, moving in larger and larger circles until you reach the outer edge of the breast. Also move your fingers up and down vertically, in rows. Begin examining each area just beneath your skin with a very soft touch, and then increase pressure so that you can feel the deeper tissue, down to your ribcage using fingers only.
Step 5
- Feel your breasts while you are standing or sitting.
- It is easier to feel your breasts when their skin is wet and slippery (like while taking bath).
- Cover your entire breast, using the same hand movements described in Step 4.
-
Do Monthly Breast Self Examination!
- Mammogram test
As recommended by clinician
- Mammogram test
Breast Cancer Prevention
Prevention By Genetic Testing [23]
If you have a history of breast cancer in the family (either mother, sister or daughter with breast cancer), you can have genetic testing for the presence of BRCA1 and BRCA2 gene mutations. However, having a copy of mutated gene does not mean that you will certainly get breast cancer. If the genetic tests are positive, you may require genetic counseling and advice by your attending surgeon.
Prevention by changing lifestyle-related risk factors [24]
- maintain correct body weight
- exercise regularly
- avoid smoking and excessive alcohol
- breast-feed
- avoid unnecessary radiation exposure.
Breast Cancer Staging [25]
Cancer stage is based on following characteristics:
- the size of the lesion/lump/tumor
- whether the cancer is invasive
- whether cancer is in the lymph nodes
- whether the cancer has spread to other parts of the body beyond the breast
TNM staging system
The TNM system is based on
- Tumor size (T stands for tumor)
- Lymph node involvement (N stands for node)
- Whether the cancer has metastasized (M stands for metastasis), or moved beyond the breast to other parts of the body.
Treatment of Breast Cancer
Different ways to treat breast cancer include
- Surgery
- Radiotherapy
- Chemotherapy
- Hormone therapy
Your individual treatment is planned based on following factors:
- clinical stage of breast cancer
- histopathologic grade of cancer
- menopausal status
- presence or absence of hormone receptors
- overall general health
Surgery for Breast Cancer
The type of surgery will depend on:
- The size of the cancer in the breast
- Whether it has spread to any other part of the body
- The size of the breasts
Different types of surgery are as follows:
- Lumpectomy: only the lump/tumor or area of cancer is removed
- Quadrantectomy: about a quarter of the breast tissue involved by the tumor is removed
- Simple mastectomy: removal of the breast tissue (including the skin and the nipple) and the tissues that cover the chest muscles
- Radical mastectomy: removes the muscles of the chest wall along with the structures mentioned in mastectomy
- Modified radical mastectomy: removal of breast, nipple, lymph nodes in armpit but chest wall muscles are spared
Radiotherapy for Breast Cancer
Radiotherapy treatment uses ionizing radiation to destroy cancer cells. It is a common treatment for breast cancer after surgery. After breast-conserving surgery (lumpectomy or wide local excision), women usually have radiotherapy to the whole of the remaining breast tissue.
External beam radiation: This is the type most commonly used type of radiotherapy for breast cancer. External beam radiation works by focusing a beam of radiation from a machine to its target, the area of the body affected by cancer.
Brachytherapy: This type of radiotherapy uses an implant to deliver radiation to the cancer. For breast cancer, radioactive seeds or pellets are placed inside the breast near the cancer.
Chemotherapy for Breast Cancer
Chemotherapy refers to the use of anti-cancer drugs to kill breast cancer cells. Chemotherapy can be used for three major purposes:
- Adjuvant therapy: The goal is to prevent or postpone cancer from coming back after the initial surgery and radiation. Even when the cancer seems to be confined to the breast and lymph glands under the arm, there is a chance that cells may have already spread to other areas that cannot be seen. Chemotherapy is given to try and kill these cells.
- Neo-adjuvant therapy: The chemotherapy drugs are given before the surgery to shrink the tumor to make the surgery easier.
- Treatment of metastatic disease: Chemotherapy can be one of the main ways to kill cancer cells that have spread to other parts of the body.
Some of the most common chemotherapy drugs used to treat breast cancer include the following:
- Paclitaxel
- Carboplatin
- Adriamycin
- Cyclophosphamide
- 5 Fluorouracil
- Herceptin: This drug is only of use in women whose breast cancers have the HER-2 gene
Hormone Therapy for Breast Cancer
Hormone therapy is used in women with certain types of breast cancer whose tumors are sensitive to estrogen or progesterone (hormones that cause the cancer to grow). Not all breast cancers are hormone-sensitive, so not all breast cancers will respond to a hormone-blocking treatment.
These drugs slow or stop the growth of cancer cells possessing hormone receptors. As an add-on therapy, endocrine therapy helps prevent the original breast cancer from returning and also helps reduce the risk of the development of new cancers in the other breast.
References
[1] http://www.breastcancer.org/symptoms/understand_bc/what_is_bc
[2] Hotko YS. Male breast cancer: clinical presentation, diagnosis, treatment. Exp Oncol 2013;35:303-10
[3] http://www.who.int/cancer/detection/breastcancer/en/
[4] Agarwal G, Ramakant P. Breast Cancer Care in India: The Current Scenario and the Challenges for the Future. Breast Care (Basel). 2008;3:21-27
[5] GLOBOCAN 2012 (IARC), Section of Cancer Surveillance (15/1/2015)
[6] http://www.webmd.com/women/picture-of-the-breasts
[7] http://www.cancer.org/cancer/breastcancer/detailedguide/breast-cancer-risk-factors
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[9] Collaborative Group on Hormonal Factors in Breast Cancer. Menarche, menopause, and breast cancer risk: individual participant meta-analysis, including 118,964 women with breast cancer from 117 epidemiological studies. Lancet Oncol 2012;13:1141-51
[10] Vrieling A, Buck K, Kaaks R, et al. Adult weight gain in relation to breast cancer risk by estrogen and progesterone receptor status: a meta-analysis. Breast Cancer Res Treat 2010;123:641-49
[11] Ewertz M, Duffy SW, Adami HO, et al. Age at first birth, parity and risk of breast cancer: a meta-analysis of 8 studies from the Nordic countries. Int J Cancer 1990;15;46:597-603
[12] Collaborative Group on Hormonal Factors in Breast Cancer. Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50?302 women with breast cancer and 96,973 women without the disease. Lancet 2002;360:187-95
[13] Rinaldi S, Peeters PHM, Bezemer ID, et al. Relationship of alcohol intake and sex steroid concentrations in blood in pre- and post-menopausal women: the European Prospective Investigation into Cancer and Nutrition. Cancer Cause Control 2006;17:1033-43
[14] American Cancer Society.Signs and Symptoms. Accessed at http://www.cancer.org/cancer/breastcancer/index on January 15, 2015
[15] Acton A, Breast Cancer: New Insights for the Healthcare Professional, ScholarlyEditions, Atlanta; 2011
[16] http://www.harrisburghealthystart.com/2012/10/what-is-breast-cancer/
[17] Sharma S. K., Alternate Therapies, Diamond Pocket Books (P) Ltd.; 2000
[18] http://www.nlm.nih.gov/medlineplus/ency/article/001515.htm
[19] American Cancer Society. Breast Cancer Early Detection. Accessed at http://www.cancer.org/cancer/breastcancer/index on January 15, 2015
[20] http://www.cancer.org/cancer/breastcancer/detailedguide/breast-cancer-diagnosis
[21] American Cancer Society. Detailed Guide: Breast Cancer. 2014. Accessed at http://www.cancer.org/Cancer/BreastCancer/DetailedGuide/index on November 13, 2014
[22] American Cancer Society. Breast Cancer Prevention and Early Detection. 2014 Accessed at http://www.cancer.org/cancer/breastcancer/detailedguide/index on January 15, 2015
[23] http://www.cancerresearchuk.org/about-cancer/type/breast-cancer/about/risks/breast-cancer-genes
[24] http://www.cancer.gov/cancertopics/pdq/prevention/breast/Patient
[25] American Joint Committee on Cancer 7th Edition. Breast Cancer Staging. American Cancer Society. 2009. Accessed at https://cancerstaging.org/references-tools/quickreferences/Documents/BreastMedium.pdf