By Renu Agrawal
Changes in the breast tissue causes breast cancer. There is usually a lump in the breast, change in the shape or colour of the breast, the skin may have some dimples or sometimes a fluid secretes from the nipple. There is a lot of bone pain, the lymph nodes get swollen and the person finds difficulty in breathing and weight loss.
There can be many different causes to have this disease like obesity, if there is no physical exercise, consumption of alcohol, hormone replacement therapy during menopause, exposure to ionizing radiation, if the menstruation has started at an early age, if a women has children either very late or does not give birth to any child, old age and family history of breast cancer.
Commonly, the cancer develops from the lining of milk ducts and the lobules that supply the ducts with milk known as ductal carcinomas and lobular carcinomas respectively.Ductal carcinoma in situ, develop from pre-invasive lesions.Usually a biopsy is done to confirm the disease and to start the treatment in the right direction. Breast cancer presents as metastatic disease where it can spread to other parts of the body. There are lot of controversies if mammography is good or has side effects. Usually medications like tamoxifen or raloxifene or even removal of breasts are recommended to women with great risk. It may reduce the risk of breast cancer but increases the risk of thromboembolism and endometrial cancer.
There are some reports that conclude that use of oral contraceptives may cause premenopausal breast cancer. It has been reported that who carry the BRCA1 and BRCA2 gene mutation or even estrogen exposure may develop hereditary breast–ovarian cancer syndrome. This interferes in the repair of DNA cross links and DNA double strand breaks. If fibrocystic breast changes take place in benign breast conditions it may cause the disease. There are protective pathways namely PI3K/AKT and RAS/MEK/ERK. However, when the genes along these protective pathways are mutated it may cause cancer. Breast adipose tissue and overexpression of leptin also leads to increased cell proliferation and cancer.
There are different stages to this disease. These include:
Stage 0 is a pre-cancerous or marker condition. This is either ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS).
2.Stages 1–3 are within the breast or in the lymph nodes of that particular region.
3.Stage 4 is ‘metastatic’ cancer in which the cancer cells spread beyond the breast and regional lymph nodes.
Prevention: It is possible to prevent the disease (20-40%) by maintaining a healthy weight, drinking less alcohol, exercising and breast-feeding. It has been found that eating citrus fruits, omega-3 polyunsaturated fatty acids and soy-based foods, a high dietary intake of calcium showed 33% lower risk of breast cancer helps in preventing the disease. Vitamin D is also known to reduce the risk of breast cancer. Broccoli, cauliflower, cabbage, kale and Brussels sprouts,mushrooms and green tea and right dose of iodine helps to reduce the disease. Monoclonal antibodies or other immune-modulating treatments are carried out many times.
There are some standard surgeries like mastectomy (removal of the whole breast), Quadrantectomy (removal of one-quarter of the breast) and Lumpectomy (removal of a small part of the breast) takes place.Some breast cancers require estrogen to continue growing. These ER+ cancers can be treated with drugs that block the receptors. Medicine like tamoxifen, or alternatively block the production of estrogen with an aromatase inhibitor, e.g. anastrozole or letrozole. The usage period is though quite high. For tamoxifen it is recommended to be used for 10 years, whereas, Letrozole is recommended for 5 years. It has been seen that after menopause aromatase inhibitors are more suitable. It should not be given to premenopausal women with intact ovarian function.
Breast reconstruction surgery is possible by plastic surgery. Chemotherapy or other types of therapy prior to surgery are called neoadjuvant therapy. Aspirin may reduce mortality from breast cancer. Chemotherapy is mostly used if the patient is in stages 2–4 which are usually given in combinations for 3–6 months. Doctors usually give a combination of cyclophosphamide with doxorubicin called as AC. It kills the cancer cells but damage of fast-growing normal cells with severe side effects. Radiotherapy is given after surgery to the region of the tumor and regional lymph nodes. This destroys the microscopic tumor cells that would be still present even after the surgery.
Breast cancer in males is mostly detected at later stages and therefore is very severe.
(The writer is former Chief Scientist, CFTRI).