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Breast Cancer, BRCA2 Gene Breast Cancer Breast cancer specifically refers to a cancer that forms in tissues of the breast Usually in the ducts – which are the tubes that carry milk to the nipple Or the lobules – glands that make milk It occurs in both men and women
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Breast Cancer • Breast cancer specifically refers to a cancer that forms in tissues of the breast • Usually in the ducts – which are the tubes that carry milk to the nipple • Or the lobules – glands that make milk • It occurs in both men and women • Male breast cancer is rare
Prevalence • One in eight women in the US will develop Breast Cancer • Male breast cancer – 1% of the population • Age and new occurrences per 1000 women • 35-39 : 0.5 • 40-44 : 1.0 • 45-49 : 1.6 • 50-54 : 1.7 • 55-59 : 1.9
Estimated Statistics for US in 2007 New Cases: Women (178,480) Men (2030) Deaths: Women (40,460) Men (450)
Could you have it? • Common Symptoms: • How the breast or nipple feels: nipple tenderness, lump on the breast • How the breast looks: change in size or shape, scaly/red/swollen areas of the skin • Nipple Discharge
Prognosis: with Breast Cancer, it depends on the severity when detected. Earlier detection yields stronger survival rates Examples from the American Cancer Society below: • 100% of women survive breast cancer if it is detected before it starts to spread • 88% of women survive breast cancer if it is detected while it is 2-5cm in diameter and has spread to axillary lymph nodes • 56% of women survive breast cancer if it is detected after it has spread to axillary lymph nodes and to axillary tissues • 49% of women survive breast cancer if it is detected after it has attached itself to the chest wall and chest lymph nodes • 16% of women survive breast cancer if it is detected after it has spread to other parts of the body such as bone, lung or liver
The Genetics of Breast Cancer • BRCA1 and BRCA2 are both tumor suppressor genes and mutations lead to an increased risk of developing breast cancer • BRCA1 and BRCA2 mutations account for 5-10% of breast cancer cases today • With the mutation, a person is 3-7 times more likely to develop breast cancer
Risks for developing Breast Cancer Person without a mutated copy of BRCA2 gene Person with a mutated copy of BRCA2 gene
BRCA2 = Breast Cancer 2, Early Onset • Located on the long arm (q) of chromosome 13 • The protein is a DNA repair protein • Works with RAD51 • Protein large, ~20 exons • Autosomal Dominant
BRCA2 and Breast Cancer • Over 800 mutations of the BRCA2 gene identified • Lead to the production of an abnormally small, nonfunctional protein unable to repair damaged DNA or fix mutations occurring in other genes • Mutations lead to cancer when the second (unmutated) copy of BRCA2 gene is lost • Other cancers: esp. prostate, but also ovarian & pancreatic • If two copies of the mutated BRCA2 gene inherited = Fanconi anemia
WHO? • About 2.3% of individuals of Ashkenazi Jewish descent have a mutated or “altered” BRCA1 or BRCA2 gene. • The most common BRCA2 mutation found in Ashkenazi Jews is the 6174delT mutation • This mutation is thought to have a frequency of .3% among Ashkenazi Jewish
WHO? cont. • People with a close family member who is known to have the mutation (which can be inherited from either the mother or the father) • People with a family member who got breast or ovarian cancer before the age of 50 • Those who have a male family member with breast cancer
Also, the frequency of this gene mutation is also higher in people of Norwegian, Dutch, and Icelandic origin
What Does a Positive Result Mean? • A person who has inherited a mutation on the BRCA2 gene has an increased RISK of getting certain types of cancer associated with the mutation • It is impossible, however, to determine from this result whether or not the individual will actually get cancer • A mutated BRCA2 gene produces protein that cannot carry out its normal function in helping to fix mutations, leading to a build up of mutated cells in the form of a Tumor
What Does an Ambiguous Result Mean? • Sometimes, it is not possible to tell whether certain alterations found during testing will increase the risk of getting cancers associated with the mutation. This is called an ambigious result.
Why? • People get tested so that they can make better, more informed decisions about what actions to take in the future • For example, people who test positively may choose to get preventative treatments involving surgery and/or medication • Some people testing positively choose to participate in medical research that could decrease their chances of getting cancer • Different test results can also affect people’s decision about having children
Problems With Getting Tested • Most problems associated with getting tested are psychological, for example… • People cannot deal with their results emotionally • If they test positive then they may become depressed • If they test negative they may feel guilty for not having the mutation while other family members do • Test results can affect people’s decisions regarding marriage and having children
More Problems with Getting Tested • Receiving genetic counseling before and after testing is very important • Confidentiality of results is not guaranteed if they are placed in a patient’s medical records • Insurance companies may find out and insurance prices could shoot up • Positive results may lead to genetic discrimination by insurance companies and employers
How? • Testing for mutations or alterations in the BRCA2 gene can be done through a simple blood test • Some insurance policies cover testing while others do not • 450 mutations have been identified in the BRCA2 gene, but there are many more yet to be identified • If a person has a mutation that has not yet been identified, his/her test result might be incorrect • Most of these mutations involve insertions or deletions of base pairs
Kaiser Permanente Criteria forBRCA1/2 Genetic Testing • Women with breast cancer plus one of the following… B. Women with ovarian cancer plus one of the following… C. Men with breast cancer plus one of the following… D. Women or men without personal history of breast cancer, but with family history of breast and/or ovarian cancer plus one of the following…
Video of a “Previvor” http://video.on.nytimes.com/?fr_story=0aff7eb1147f98a41e989541f3fc114c8e71dcd2
Surgery • Lumpectomy-tumor and surrounding tissue removed. • Partial Mastectomy-cancer tissue is removed along with a portion of the surrounding breast tissue. • Total Mastectomy-entire breast is removed. • Modified Radical Mastectomy-entire breast, the lining over the chest muscles, many of the underarm lymph nodes are removed. • Radical Mastectomy-entire breast, the underlying chest muscle, and all of the underarm lymph nodes are removed.
Therapy • Radiation therapy- X-rays can be used to shrink or kill the cancer cells at the tumor site. • Hormone therapy- some types of breast cancer have receptors that are affected by different hormones.
Chemotherapy- Drugs are injected or taken orally to kill the cancer cells. • Clinical treatment- experimental treatments are available for breast cancer.
Side Effects • Chemotherapy • Nausea and vomiting • Loss of appetite • Loss of hair • Mouth sores • Increased susceptibility to infection • Premature menopause • Infertility
Radiation therapy • Occasional fatigue • Swelling and heaviness in the breast • Skin changes similar to sunburn at the affected site • Breasts can possibly become smaller and firmer after treatment • Can contribute to swelling of the arm if underarm is irradiated after surgery. • Hormone therapy • Depends on the specific medication used and the individual patient • A doctor should be consulted about the possible side effects before beginning treatment.
Post-treatment therapy • Doctors may refer their patients to support groups, councilors, or a psychologist for help in dealing with the aftermath of the disease and treatment. • Breast reconstruction surgery • Latissimus Dorsi flap: a section of skin, fat, and latissimus dorsi muscle is transferred from the back to the breast area and shaped into a natural-looking breast. • TRAM flap: a section of skin, fat, and muscle is transferred from the lower half of the abdomen to the breast area and shaped into a natural-looking breast. • Breast Implants
Breast Cancer Risk Calculator! http://www.cancer.gov/bcrisktool/ The room will split up into two halves. As we go through the questions, choose the answers that you think will maximize a person’s risk of getting breast cancer.