<p>Biology 207 Fall 2005 Biology of Cancer</p><p>Lecture 29 "Breast Cancer"</p><p>Readings: King p. 278, Bazell (1998) Her-2</p><p>Outline: 1. Breast cancer statistics 2. Major types of breast cancer 3. Risk factors 4. Detection of breast cancer 5. Treatments </p><p>Lecture: </p><p>1. Breast cancer statistics</p><p>--1:8 chance of breast cancer for women in their lifetimes --Leading cause of cancer death in women aged 40-55 --Male breast cancer about 1% of cases</p><p>2. Major types of breast cancer</p><p>Breast--specialized gland that produces milk to nourish infants.</p><p>Glands--epithelia that secrete substances.</p><p>Anatomy--lobules=site of milk production --ducts=carry milk to nipple</p><p>80% of cases: invasive ductal carcinoma (IDC) 10-15% of cases: invasive lobular carcinoma (ILC)</p><p>3. Risk factors for breast cancer</p><p>--age --previous cancer in one breast --family history 5-10% of breast cancers BRCA1 BRCA2 p53 --benign breast disease (fibrocystic disease) cysts--fluid filled sacs fibrosis--scar tissue (connective tissue) formation --early menstruation</p><p>1 --late menopause --no children or birth of first child after age 30</p><p>Reduce risk by</p><p>--low fat diet --exercise? --stop smoking --limit alcohol --not taking the pill? --limited use of estrogen replacement therapy --avoid pesticides, environmental chemicals</p><p>Recommendations for women with family history of breast cancer --gene testing (and counseling)? --tamoxifen (anti-estrogen therapy) or raloxifen (trial) --prophylactic (preventative) mastectomy?</p><p>4. Detection of breast cancer --breast self exam (BSE), monthly after age 20 --clinical breast exam --mammogram after age 40, every 1-2 yrs --confirmation by mammogram, ultrasound, &/or biopsy</p><p>Breast cancer staging: TNM system, simplified to stages 0-IV</p><p>Stage 5 year survival rate</p><p>O 100% I 98% IIA 88% IIB 76% IIIA 56% IIIB 49% IV 16% metastatic breast cancer</p><p>5. Treatments --surgery (type depends on stage of cancer) lumpectomy partial mastectomy total mastectomy modified radical mastectomy radical mastectomy</p><p>--radiation therapy --hormone therapy (anti-estrogen therapy, such as tamoxifen)</p><p>2 --chemotherapy --rarely, bone marrow transplant --for Her-2/neu positive tumors, antibody therapy</p><p>3</p>