Transcript - Catalyst
CHAPTER SIXTEEN: CANCER MAY 18, 2012 Albert J. Farias, MPH PhD ‘14 Today’s talk: Normal cell growth What is cancer Disparities in cancer outcomes Risk factors (modifiable and non-modifiable) Screening recommendations Common cancers Healthy Cell Growth • Divide when needed to replace cells that have died or been sloughed off (different rates, different cell types) • ~1014 cells in adults • ~1016 divisions in a lifetime • Complicated system of checks and balances that control cell growth and division. • Send and receive messages from other cells • Healthy cells (except blood cells) require presence of neighboring cells for growth - stick together Healthy Cell Growth – safety checks • • • Repair mechanisms Each time a cell divides, there is a possibility of mutation or an error in DNA replication. Enzymes in nucleus scan DNA for errors- repair or destroy • Pre-programmed number of cell divisions • Immune system monitors Overview: Normal versus Cancer cells http://www.youtube.com/watch?v=Q9cuEYSt0GE&fe ature=youtu.be What Is Cancer? Condition characterized by the uncontrolled growth of cells Develops from a single cell that goes awry, but a combination of events must occur before the cell turns into a tumor Clonal growth: replication of a single cell that produces thousands of copies of itself in an uncontrolled manner Cancer is categorized based on the function/location of the cells from which they originate Cancer Cell Characteristics Cancer- Carcinoma (Gr. Crab) Hippocrates, 460-370 BCE . Cytoskeletal changes (affects interactions with neighbor cells) . Cell adhesion/motility . Nuclear changes (shape and organization) . Enzyme production (evade neighboring tissue) Cancer Cell Growth Starts from a single cell that is undergoes a critical mutation caused by: an error in duplication in response to a carcinogen, a cancer causing substance Radiation Initiating event: allows a cell to evade one of the protective restraints For cell to become cancer- must evade other constraintsusually series of 5-10 mutations required Oncogene: a gene that drives a cell to grow and divide regardless of signals from surrounding cells Cancer Cell Growth Tumor: mass of extra tissue Benign - slow growth and unlikely to spread; can be dangerous or fatal in certain locations Malignant - capable of spreading to surrounding tissues (don’t stick together) Metastasis: secondary tumor that appears when cancerous cells spread to other parts of the body © 2009 McGraw-Hill Higher Education. All rights reserved. Stem Cells • • • Embryonic or adult – important to distinguish Stem cells pose a greater risk for cancer (omnipotent) but have special protective mechanisms. Located deep within tissues and are protected from factors that increases the risk of genetic mutation (exposure to the sun, chemicals, and irritation). © 2009 McGraw-Hill Higher Education. All rights reserved. Types of Cancer Four broad types of cancer are distinguished: • Carcinomas: arise from epithelial tissue, (skin, lining of the intestines and body cavities, surface of body organs, outer portion of glands) and represents about 80% of all cancer cases • Sarcomas : arise from connective tissue (bone, tendon, cartilage, muscle, fat tissues) • Leukemias: cancers of the blood originate in the bone marrow or the lymphatic system • Lymphomas: cancers that originate in lymph nodes and glands • Myeloma: cancer involving the white blood cells responsible for production of antibodies (B lymphocytes or B-cells) Death rates For men Death rates For women U.S. Mortality Data 1960-2004.National Center for Health Statistics Centers for Disease Control and Prevention, 2006 Cancer Disparities: Diagnosis and Outcomes The National Cancer Institute (NCI) defines "cancer health disparities" as adverse differences in cancer incidence (new cases), cancer prevalence (all existing cases), cancer death (mortality), cancer survivorship, and burden of cancer or related health conditions that exist among specific population groups in the United States. These population groups may be characterized Age Gender Income Disability Education Location Cancer Disparities: Diagnosis and Outcomes Discussion: What are things that could account for the differences in cancer outcomes among groups of people? Think about what we’ve talked about in class (where you live, health behaviors). Cancer Disparities Lack of medical coverage barriers to early detection and screening unequal access to improvements in cancer treatment Aggressive breast tumors are more common in younger African American/Black and Hispanic/Latino women living in low SES areas. Less responsive to standard cancer treatments and is associated with poorer survival Risk Factors for cancer Modifiable versus non-modifiable risk factors Think about duration, frequency, and timing of exposures Cancer Prevention Primary Secondary Tertiary Risk factors for cancer Family History (genetics) BRCA1 and BRCA2 (60% increased risk versus 12% risk in general population) Risk Factors for Cancer • Environmental Factors – – – – – – Ultraviolet radiation Other forms of radiation Chemical and physical carcinogens Infectious agents Asbestos Magnetic field exposure Risk factors for cancer • Lifestyle factors – – – – – – Tobacco use Dietary patterns Overweight and obesity Physical inactivity Alcohol consumption Reproductive factors (pregnancy, abortion, menstruation) Infections HPV H. pylori infection Chronic Inflammation (hepatitis) Other possible factors Antiperspirants Artificial Sweeteners Acrylamide Pesticides Cell phone use Chronic stress Screening Recommendations Screening recommendations (women) Breast cancer: Mammograms biennial starting age 50 Self breast exam? Clinical breast exam? High risk: earlier, MRI, ultrasound? Cervical Cancer: Pap screen- age 21 HPV vaccine Endometrial cancer: report unexpected bleeding (esp after menopause) endometrial biopsy Screening recommendations (men) Testicular cancer: controversy over self exam Prostate cancer: PSA blood test - offered age 50 Digital High rectal exam risk: offer starting age 40 Screening recommendations (men and women) Colon cancer: flexible sigmoidoscopy or colonoscopy or barium enema starting at age 50 annual stool fecal occult blood test Lung cancer: controversial Common cancers Testicular Prostate Breast Cervical Ovarian Lung Colorectal Skin Oral Leukemia Lymphoma Most common cancers 15-39 year olds Type men women All sites 51.2 (vs 1202 >40) 81.6 (vs 873.8 >40) Lymphoma 8.5 6.8 Leukemia 3.5 2.5 Germ cell 10.5 1.0 Soft tissue sarcomas 3.4 2.4 Melanoma and skin CA 5.6 9.6 Thyroid cancer 13.7 2.7 Gastrointestinal 5.7 4.9 CNS 3.1 2.5 Per 100,000 Cancer Treatment Surgery Radiation therapy Chemotherapy Immunotherapy Targeted therapy Hormonal therapy Common Cancers – all age groups • Lung Cancer • • • Colon and Rectal Cancer • • • 3rd leading cause of death 3rd most commonly diagnosed cancer Breast Cancer • • Leading cause of cancer death in the US Second most commonly diagnosed cancer Second leading cause of cancer death in women Prostate Cancer • • Second most common cause of cancer death in men Most commonly diagnosed cancer for men Lung Cancer • Risk Factors – – • Smoking Exposure to carcinogenic chemicals, arsenic, radon, asbestos, radiation, air pollution, and environmental tobacco smoke Symptoms – – – – – Coughing Blood-streaked sputum Chest pain Difficulty breathing Recurrent lung infections Lung Cancer • Prevention – • • Remove smoke element Early detection? Treatment – – – – Surgery Radiation Chemotherapy Radiation and Chemotherapy combination Colon and Rectal Cancer • Risk factors – – – – • Age Genetic and dietary habits Personal or family history of colon polyps, inflammatory bowel disease, colorectal cancer Smoking, obesity, physical inactivity, diet high in fat or red or processed meat, diet inadequate in fruit and vegetables Warning signs – – – – Change in bowel movements Change in stool size or shape Pain in the abdomen blood in the stool Colon and Rectal Cancer • Early Detection – • Rectal exams, stool test, sigmoidoscopy, colonoscopy, double-contrast barium enema, CT colonography Treatment – Surgery, radiation and/or chemotherapy Breast Cancer Risk factors – – – – – – – – – Early first menstruation Late onset of menopause Family history Older age Higher socioeconomic class Women with no children or having children after 30 Obesity after menopause Hormone replacement therapy use Drinking more than two alcoholic beverages a day Breast Cancer • Prevention – – – – • Screening/detection – – • Diet Exercise Maintaining healthy body weight Pregnancy and breastfeeding decisions Breast self-exam Mammography Treatment – – – Lumpectomy Mastectomy Radiation and/or chemotherapy treatments © Royalty-Free/Corbis Prostate Cancer • Risk factors – – – – • Age Family history Being Black High-fat diet Symptoms during the advanced stage – – – – Difficulty urinating Pain in the pelvic region Pain with urination Blood in the urine Prostate Cancer • Early Detection – – • Digital rectal exam Prostrate-specific antigen (PSA) screenings Treatment – – – – Surgery Radiation, sometimes in combination with chemotherapy Hormonal medications Vaccine Cancers of the Female Reproductive System Cancer can develop throughout the female reproductive system but occurs more frequently in the following areas: • • • Cervix Uterus Ovaries Cervical Cancer • Risk factors – • • • HPV infection (cervical dysplasia), tobacco use, immuno-suppression, multiple births, early sexual activity, multiple sex partners, socioeconomic status, and nutritional status Early detection through PAP test has significantly reduced the rates of cervical cancer and mortality – HPV detection HPV Vaccine Treatment – – – – Electrocoagulation Cryotherapy Surgery Radiation/chemotherapy Ovarian Cancer • The leading gynecological cause of cancer death and the fifth overall cause of cancer in women – Risk factors • • – Prevention • • • • – – Family history Personal history of breast, colon, or endometrial cancer Using oral contraception Pregnancy Breastfeeding Avoiding postmenopausal hormone replacement therapy Early detection?? Treatment • Surgery, chemotherapy, drug therapy Skin Cancer • 3 forms of skin cancer: • • • • Risk factors – – – • • Severe sunburn during childhood, chronic sun exposure during young adulthood, cumulative sun exposure Large number of moles Family history Prevention – • Basal cell cancer (lesions and sores) Squamous cell cancer (raised bumps and sores) Melanoma (spreads quickly) Reduce exposure to sun’s rays, use sunscreen Early detection: skin exams Treatment – Surgery, local removal, chemotherapy, immunotherapy ABCD Evaluation of Moles for Melanoma Testicular Cancer Most common cancer for men aged 20-35 Risk factors Detection - controversial Family history, personal history of testicular cancer in other testicle, abnormal development of the testes, history of undescended testicle, infertility or abnormal sperm Self exams Medical exams Treatment Surgery, chemotherapy, radiation Oral Cancer Cancers that develop in the mouth or the pharynx Risk factors include: Early signs include: Cigarettes, cigars, pipes, smokeless tobacco High levels of alcohol consumption Persistent sore in the mouth Lump or bump that won’t heal Patch of white or red along the gums or cheeks Treatment Surgery Chemotherapy Radiation Leukemia • • • Group of cancers - originate in the bone marrow or other parts of the body where white blood cells form Overproduction of one type of white blood cell and can lead to increased risk of infection, anemia, and bleeding Risk factors are: • • • • Cigarette smoking and exposure to chemicals Ionizing radiation exposure Infection with a virus Treatment • • Chemotherapy Possible bone marrow transplant Lymphoma • Cancers that originate in the lymph system, part of the body’s immune system – – • Hodgkin’s lymphoma Non-Hodgkin’s lymphoma Risk factors are: • • • Infections, medications, or genetic change that weaken the immune system Radiation, herbicides, insecticides, and some chemical exposures Treatment • • Often includes a combination of surgery, chemotherapy, and radiation Can sometimes involve immunotherapy or bone marrow transplant Questions?