Chapter 12-->Cancer

•Group of diseases characterized by uncontrolled growth and spread of abnormal cells •Cell growth or reproduction takes place to repair and replace old, worn-out tissue •Cell growth is controlled by DNA and RNA, found in the nucleus of each cell

•Genetic substance of which genes are made; molecule that contains cell’s genetic code

•Genetic material that guides the formation of cell proteins

–Benign: Noncancerous –Malignant: Cancerous

•Cancer starts with the abnormal growth of one cell, which then can multiply into billions of cancerous cells •A critical turning point in the development of cancer is when a tumor reaches about one million cells •At this stage, it is referred to as carcinoma in situ •The undetected tumor may go for months or years without any significant growth •While encapsulated, it does not pose a serious threat to human health •To grow, the tumor requires more oxygen and nutrients

•In time, a few cancer cells start producing chemicals that enhance angiogenesis (capillary or blood vessel formation into the tumor)

•Angiogenesis is the precursor of metastasis (movement of cells from one part of the body to another) •Through the new blood vessels formed by angiogenesis: –Cancerous cells break away from a malignant tumor –They migrate to other parts of the body –They can cause new cancers

•Cancer is the second leading cause of death in the U.S. •Leading cause of death in children between ages 1 and 14 •Lung cancer is the major contributor to the increase in incidence of cancer •Tobacco use alone is responsible for 30% of all deaths from cancer •Another third of all deaths from cancer are related to unhealthy nutrition, physical inactivity, and excessive body fat

–Diet –Obesity –Tobacco use –Sedentary lifestyle –Excessive use of alcohol –Exposure to occupational hazards

•One-third of all cancer in the U.S. is related to poor nutrition and lack of physical activity •A healthy diet is crucial to decrease the risk for cancer •Predominately a vegetarian diet (high in fiber and low in fat) •Cruciferous vegetables, tea, soy products, calcium, and omega-3 fats are encouraged •Protein intake should be kept within the recommended guidelines •Alcohol should be used in moderation •Avoid obesity

•Too much alcohol raises the risk of developing certain cancers •Consuming alcohol in combination with tobacco use increases the risk for cancers of the mouth, larynx, throat, esophagus, and liver •About 17,000 cancer deaths yearly are attributed to excessive use of alcohol, often in combination with smoking

•All related deaths included, smoking is responsible for more than 440,000 unnecessary deaths in the U.S. each year •Average life expectancy for a chronic smoker is about 15 years shorter than for a nonsmoker •At least 30% of all cancers and 87% of lung cancers are tied to smoking •Smokeless tobacco can lead to nicotine addiction, as well as increased risk for cancers of the mouth, larynx, throat, and esophagus

As little as 15-30 minutes of exposure to UVA rays can be dangerous Apply sunscreen lotion about 30 minutes before lengthy exposure to the sun

•Consult with your physician if you are at high risk for any form of cancer •Of all cancers, 60%-80% are preventable, and about 50% are curable •Most cancers are lifestyle related, so being aware of the risk factors and following the screening guidelines and basic recommendations for preventing cancer will greatly decrease your risk for developing it

•Physical activity •Fiber •Fruits and vegetables •Recommended weight •Healthy grilling •Tea •Spices •Vitamin D •Monounsaturated fat