By Deepa K - The cancer found in the cells of the breast is Breast cancer. A mass of breast tissue that is growing in an abnormal and uncontrolled way is a cancerous tumor. A cancerous tumor may attack the surrounding tissues or shed cells into the blood stream or lymph system. After lung cancer, breast cancer is the second most common type of cancer found world wide and fifth most common cause of cancer death. This is the most common cause of cancer among women in incidence as well as death. It caused 502,000 deaths worldwide in 2005. The number of cancer cases increased from 1970 which should be blamed on the modern styles of the present day world. Breast cancer is the most feared disease by women than the much more common fatal heart attack among women. The death rates for this cancer are declining for the last few years.
This type of cancer also occurs in men as the breast in males and females consists of same type of tissues. But it is 100 times lesser than the women and it has the same survival rates as women. The tumor in the breast is very hard to feel and have and irregular shape and not smooth. During a breast self exam the cancerous tumor may not move but the tissues around the tumor may move.
The cancer begins as single or more cells which lost its control of differentiation and increase but remains restricted with in the basement membrane of the duct. These divides and they invade the basement membrane of the duct and ultimately spread to distant organs also.
Four different classification or groups based on different reason and have a different purpose describes breast cancer:
(a) Pathology - Each tumor based on its histological appearance and for other reasons is categorized by the pathologist. The categories are invasive ductal carcinoma, malignant cancer in the ducts of the breast, invasive lobular carcinoma and the malignant cancer in the breast lobules.
(b) The pathologist determines the histological grade of the tumor under a microscope. A low grade tumor resembles normal tissue. A high grade tumor does not look like a normal tissue and composed of disorganized cells. Intermediate grade is in between the high and low grade.
(c) All breast cancers should be tested for expression or detectable effect of the estrogen receptor(ER), progesterone receptor (PR) and HER2/neu proteins and are done by immunohistochemistry and will be shown in the pathologist's report. To predict the prognosis, the profile of expression helps the oncologist to choose the proper treatment.
(d) Stage of a tumor-The TNM classification is the currently accepted staging scheme and it is as follows:
Tumor- Depends upon the presence or absence of invasive cancer, the dimensions of the invasive cancer and the presence or absence of invasion outside of the breast there are five tumor classification values (Tis, T1, T2, T3 and T4).
Lymph Node- Depends on number, size and location of breast cancer cell deposits in lymph nodes there are four lymph nodes classification values (N0, N1, N2 and N3).
Metastasis- Depends on the presence or absence of the breast cancer cells in locations other than breast and lymph nodes there are two metastatic classification values (M0 or M1).
Breast cancers are not always classified by its histological appearance. Breast tumor is dense mass of cells appear whiter than the tissue around it. Benign masses are round or oval in shape but a tumor may be partially round with any shapes according to its circumference. If the mass has a multi pointed star shaped outline, it is known as speculated.
If there is a dense mass appears as tumor in a mammogram, ultrasound should be taken for that breast mass. If the mass shows an irregular outline or having fuzzy edges and is pressing the tissue around it, the person needs a biopsy of the mass. The most accurate way to diagnose its actual nature is an analysis of the tissue sample.
The exact cause of the this cancer is not known. The healthy BRCA 1 and 2 genes act as a tumor suppressor for breast and ovarian tumors. The mutated BRCA genes due to radiation or chemicals can give rise to cancer. The risk of tumor increases as the age increases. About 17% of women were diagnosed with breast cancer were in their 40s and 78% were older than 50.
General terms for this cancer
(1) Carcinoma is the term to describe a cancer that begins in the epithelial cells of organs. Most of the breast cancers are carcinomas.
(2) Adenocarcinoma which starts in glandular tissues. Glandular tissues in the breast are ducts and lobules and because of this it is known as adenocarcinoma.
(3) The early stage of cancer, when it is limited to the layer of cells where it began is described by the term Carcinoma in Situ. The cancer cells remain restricted to ducts and lobules are in situ especially in breast cancer. These types have not invaded in to the deeper tissues in the breast or spread to other organs of the body and are referred as non-invasive breast cancer.
(4) The one that has already spread beyond the layer of cells where it started are invasive or infiltrating cancer. Most breast cancers are invasive. Breast cancers are either invasive ductal carcinoma or invasive lobular carcinoma.
(5) Cancers that starts from connective tissues such as fat tissue or blood vessels are sarcomas. In the breast sarcomas are rare.
The different types of breast cancers are ductal carcinoma in situ, lobular carcinoma in situ, invasive ductal carcinoma and invasive lobular carcinoma. Less common types of breast cancers are inflammatory breast cancer, mixed tumors, medullary cancer, metaplastic carcinoma, mucinous carcinoma, Paget disease of the nipple, tubular carcinoma, papillary carcinoma, adenoid cystic carcinoma, phyllodes tumor and angiosarcoma.
Signs and Symptoms
The primary sign of this cancer is a lump that feels different that the surrounding tissue. Lump in the breast of 80% cases are discovered by the women herself. Lumps found in lymph nodes located in the armpits or collarbone can also indicate breast cancer. Other indications are change in breast size or shape, skin dimpling, nipple inversion or spontaneous nipple discharge. To determine the breast cancer, pain is an unreliable tool but can be due to other breast related problems such as mastodynia. Most of symptoms do give rise to breast cancer. Some of the common causes of breast disorder symptoms are mastitis and fibro adenoma. Any symptom should be taken seriously because there is a possibility of having cancer in the breast at any age.
Intake of plant estrogen in early adolescence such as soybeans may protect breast cancer in later life. But the intake of plant estrogen in later life is not likely to influence either positively or negatively. Avoid exposure to smoking or secondhand smoke. Passive smoking also causes breast cancer. The removal of ovaries in the high risk individuals after child bearing can reduce the risk of cancer in the breast by 60% and also in reducing the risk of developing ovarian cancer.
The most common methods for the test of breast cancer are self and clinical exams, x-ray mammography and breast magnetic resonance imaging (MRI).
By examining the surgically remove breast tissue, the breast cancer can be diagnosed. The breast tissues can be taken by fine needle aspiration, nipple aspirates, and ductal lavage, core needle biopsy and local surgical excision. The accurate diagnosis of this cancer includes radiographic imaging along with these diagnostic steps. To detect metastasis imaging tests are sometimes used and it include chest X-ray, bone scan, CAT scan, MRI and PET scanning. Microscopic evaluation of a biopsy specimen can give a cancer diagnosis.
The main treatment is the surgery of the tumor with the hormonal therapy, chemotherapy and radiotherapy. In individuals with high risk hormonal therapy has been used for chemoprevention. The US food and drug administration approved raloxifene for preventing invasive breast cancer in post menopausal women.