Document 92D0LzDX82ww360Xn3EY4zg3

CANCER FACTS & FIGURES-1995 AMERICAN VCANCER ? SOCIETY Estimated number of new cancer cases in 1995 by state, total: 1,252,000 (excluding Puerto Rico).* `Excluding basal and squamous cell skin cancer and carcinoma in situ. PUERTO RICO 10,600 R&S145013 mately 7,000 cases) and chronic lymphocytic (approxi mately 7,800 cases). Mortality: An estimated 20,400 deaths in 1995. Signs and Symptoms: Fatigue, paleness, weight loss, repeated infections, bruising easily, and nosebleeds or other hemorrhages. In children, these signs can appear suddenly. Chronic leukemia can progress slowly and with few symptoms. Risk Factors: Leukemia strikes both sexes and all ages. Causes of most cases are unknown. Persons with Down syndrome and certain other genetic abnormalities have higher than normal incidence of leukemia. It has also been linked to excessive exposure to ionizing radiation and to certain chemicals such as benzene, a commercially used toxic liquid that is also present in lead-free gasoline. Certain forms of leukemia and lymphoma are caused by a retrovirus, HTLV-I (human T-cell leukemia/lymphoma virus-I). Early Detection: Because symptoms often resemble those of other, less serious conditions, leukemia can be difficult to diagnose early. When a physician does suspect leukemia, diagnosis can be made using blood tests and biopsy of the bone marrow. TYeatment: Chemotherapy is the most effective method of treating leukemia. Various anticancer drugs are used, either in combinations or as single agents. TVansfusions of blood components and antibiotics are used as supportive treatments. To illuminate hidden cells, therapy of the central nervous system has become standard treatment, especially in acute lymphocytic leukemia. Under appro priate conditions, bone marrow transplantation may be useful in the treatment of certain leukemias. Survival: The 5-year survival rate for patients with leukemia is 38%, due partly to very poor survival of patients with some types of leukemia such as acute granulocytic. Over the last 30 years, however, there has been a dramatic improvement in survival of patients with acute lymphocytic leukemia; from a 5-year survival rate of 4% for people diagnosed in the early 1960s to 28% in the early 1970s to 52% in the mid-1980s. In children, the improvement has been from 4% to 73%. Lymphoma New Cancer Cases: An estimated 58,700 new cases in 1995, including 7,800 cases of Hodgkin's disease and 50,900 non-Hodgkin's lymphoma. Since the early 1970s, incidence rates for non-Hodgkin's lymphoma have increased over 65%. Incidence of Hodgkin's disease has declined over the same time period, especially among the elderly. Mortality: An estimated 24,150 deaths in 1995 (nonHodgkin's lymphoma, 22,700; Hodgkin's disease, 1,450). Signs and Symptoms: Hodgkin's disease: enlarged lymph nodes, itching, fever, night sweats, and weight loss. Fever 14 4 FIGURES 1995 can come and go in periods of several days or week Non-Hodgkin's lymphoma: enlarged lymph nodes, anemi weight loss, and fever. Risk Factors: Risk factors are largely unknown but part involve reduced immune function and exposure certain infectious agents. Persons with organ transplan are at higher risk due to altered immune function. Hum: immunodeficiency virus (HIV) and human T-cell leukemia lymphoma virus-I (HTLV-I) are associated with increas risk of non-Hodgkin's lymphoma. Burkitt's lymphoma Africa is partly caused by the Epstein-Barr herpes via Other possible risk factors include occupational exposur to herbicides and perhaps other chemicals. Treatment: Hodgkin's disease: chemotherapy and radi therapy are useful for most patients. Non-Hodgkir lymphoma: early stage, localized lymph node disease c be treated with radiotherapy. Patients with later sta disease often benefit from the addition of chemotheraj New programs using highly specific monoclonal antibodi directed at lymphoma cells, and improved techniques bone marrow preservation, are under investigation selected patients who relapse after standard treatment. Survival: Survival rates vary widely by cell type and sta of disease. The overall 5-year survival rate for Hodgkr disease is 79%. The overall 5-year survival for nc Hodgkin's lymphoma has steadily improved, and in t past 30 years has increased from 31% to 52%. Skin Cancer New Cancer Cases: Over 800,000 cases a year of higl curable basal cell or squamous cell cancers. They are mi common among individuals with lightly pigmented sk The most serious skin cancer is melanoma, which v be diagnosed in about 34,100 persons in 1995. Since 19' the incidence rate of melanoma has increased about per year. Incidence rates are over 10 times higher amt whites than blacks. An additional 16,000 invas nonmelanoma skin cancer cases will occur in 1995, mo: sarcomas, including Kaposi's sarcoma. Mortality: An estimated 9,300 deaths this year, 7,1 from malignant melanoma and 2,100 due to other s cancers. Signs and Symptoms: Any unusual skin conditi especially a change in the size or color of a mole or ot darkly pigmented growth or spot. Scaliness, oozi bleeding, or change in the appearance of a bump or nod* the spread of pigmentation beyond its border, a cha in sensation, itchiness, tenderness, or pain. Risk Factors: Excessive exposure to ultraviolet radiat fair complexion; occupational exposure to coal tar, pil creosote, arsenic compounds, or radium. Prevention: The sun's ultraviolet rays are stronj R&S145014 CANCER F/ Prevention Researchers estimate that if everything known about the prevention of cancerwas applied, up to two-thirds of cancers would not occur. The following are areas in which certain health choices might reduce an individual's risk of cancer. Smoking Cigarette smoking is responsible for 90% of lung cancers among men and 79% among women--about 87% overall. Smoking accounts for about 30% ofall cancer deaths. Those who smoke two or more packs of cigarettes a day have lung cancer mortality rates 12 to 25 times greater than nonsmokers. (See Tobacco Use, p. 22.) Nutrition and Diet Research is showing the important role nutrition plays in preventing cancer. Evidence indicates that people may reduce their cancer risk by observing these nutrition guidelines: 1. Maintain a desirable weight Individuals 40% or more overweight have an increased risk of colon, breast, prostate, gallbladder, ovary, and uterus cancers. Physicians can recommend a suitable diet and exercise regimen to help maintain appropriate weight and body fitness. 2. Eat a varied diet A varied diet eaten in moderation offers the best hope for lowering the risk of cancer. 3. Include a variety of vegetables and fruits in the daily diet. Studies have shown that daily consumption of vegetables and fresh fruits is associated with a decreased risk of lung, prostate, bladder, esophagus, colorectal, and stomach cancers. 4. Eat more high-fiber foods such as whole grain cereals, breads, and pasta; and vegetables and fruits. High-fiber diets are a healthy substitute for fatty foods and may reduce the risk of colon cancer. 5. Cut down on total fat intake. A diet high in fat may be a factor in the development of certain cancers, particularly breast, colon, and prostate. 6. Limit consumption of alcohol, if you drink at all. Heavy drinking, especially when accompanied by cigarette smoking or smokeless tobacco use, increases risk of cancers of the mouth, larynx, throat, esophagus, and liver. 7. Limit consumption of salt-cured, smoked, and nitritecured foods. In areas of the world where salt-cured and smoked foods are eaten frequently, there is higher incidence of cancer of the esophagus and stomach. Modem methods of food processing and preserving appear to avoid the cancer-causing byproducts associated with older methods of food treatment. Sunlight Almost all of the more than 800,000 cases of basal and squamous cell skin cancer diagnosed each year in the US are sun-related (ultraviolet radiation). Epidemiologic evidence shows that sun exposure is a major factor in the development of melanoma and that incidence increases for those living near the equator. (See Selected Cancers: Skin Cancer, p. 15.) Alcohol Oral cancer and cancers of the larynx, throat, esophagus, and liver occur more frequently among heavy drinkers of alcohol especially when accompanied by smoking cigarettes or chewing tobacco. (See Selected Cancers: Oral Cancer, P. 17.) Smokeless Tobacco Use of chewing tobacco or snuff increases risk of cancer of the mouth, larynx, throat, and esophagus and is a highly addictive habit. (See Selected Cancers: Oral Cancer, p. 17.) Estrogen Estrogen treatment to control menopausal symptoms can increase risk of endometrial cancer. However, including progesterone in estrogen replacement therapy helps to minimize this risk. Consultation with a physician will help each woman to assess personal risks and benefits. Continued research is needed in the area of estrogen use and breast cancer. (See Selected Cancers: Uterus [Cervix] Cancer, p. 12.) Occupational Hazards Exposure to several different industrial agents (nickel, chromate, asbestos, vinyl chloride, etc.) increases risk of various cancers. Risk of lung cancer from asbestos is greatly increased when combined with cigarette smoking. (See Environmental Cancer Risks, p. 20.) Ionizing Radiation Excessive exposure to ionizing radiation can increase cancer risk. Most medical and dental x-rays are adjusted to deliver the lowest dose possible without sacrificing image quality. Excessive radon exposure in homes may increase risk of lung cancer, especially in cigarette smokers. If levels are found to be too high, remedial actions should be take R&S145015 19 CANCER FACTS i FIGURES 1995 Environmental Cancer Risks The environmental causes of cancer include exposures in the community or workplace settings, as well as exposures determined by individual lifestyle choices (smoking, diet, medications, etc.). The degree of cancer hazard posed by such risks depends on the concentration or intensity of the carcinogen in the environment and the exposure dose a person receives. These factors in combination create a range of risk. For example, in situations where high levels of carcinogen are present and where exposures are extensive, significant hazards may exist, but where concentrations are low and exposures limited, hazards are often negligible. Risk Assessment To protect people against unsafe exposures, risks should be assessed so that appropriate environmental standards can be set. Risk assessment is a two-step process: identifying the toxic properties of potential oncogenic hazards and measuring the extent of human exposure. The first step, hazard identification, evaluates the chemical or physical nature of hazards and their onco genicity in observed clinical and epidemiologic studies and in laboratory tests using animals or cell systems. Special attention is given to any evidence suggesting that cancer risk may increase with dose (dose-response relationships). The second step, exposure measurement, determines the levels of hazards in the environment (air, water, food, etc.) and the extent to which people are actually exposed (how much they eat of a particular food, use a particular water source, etc.). Knowledge of how the body absorbs, metab olizes, and excretes chemicals or is exposed to radiation sources is essential to determine accurately the actual carcinogenic dose delivered to humans. Unfortunately, evidence of risk for most potential car cinogens usually rests on the results of high-dose animal experiments or on human observations where high-dose exposures have occurred. To use such information in setting human safety standards, scientists must extrapolate from animals to humans and from high-dose to low-dose conditions. Both extrapolations involve much uncertainty; therefore conservative assumptions are used so that risk assessment will err on the side of safety. For cancer safety standards, only increased risks of one case or less per million persons over a lifetime are usually accepted. Safety standards developed in this way for chemical or radiation exposures are the basis for federal regulatory activities at the Food and Drug Administration, the Environmental Protection Agency, and the Occupational Safety and Health Administration. The application of laws and procedures by which standards are implemented and risks are controlled is called risk management Chemicals and Radiation Not all chemicals or all forms of radiation cause cancer. Only a limited number of chemicals (for example, benzene, asbestos, vinyl chloride, arsenic, aflatoxins) show definite evidence of human carcinogenicity or are probable human carcinogens based on animal experiments (for example, chloroform, dichlorodiphenyltrichloroethane (DDT], for maldehyde, polychlorinated biphenyls [PCBs], polycyclic aromatic hydrocarbons). The only forms of radiation proven to cause human cancer are ionizing radiation (for example, x-rays, radon, cosmic rays) and ultraviolet radiation (principally UV-B radiation). Unproven Risks Public concern about environmental cancer risks often focuses on risks for which no carcinogenicity has been proven or on situations where known carcinogen exposures are at such low levels that risks are negligible. For example: 1. Non-ionizing radiation. Electromagnetic radiation at frequencies below ionizing and ultraviolet levels has not been shown to cause cancer. While some epidemiologic studies suggest associations with cancer, others do not, and experimental studies have not yielded reproducible evidence of carcinogenic mechanisms. Low-frequency radiation includes radiowaves, microwaves, and radar, as well as power frequency radiation arising from the electric and magnetic fields associated with electric currents (often called ELF or extremely low-frequency radiation). 2. Pesticides. Many kinds of pesticides (insecticides, herbicides, etc.) are widely used in producing and marketing our food supply. While some of these chemicals cause cancer at high doses in experimental animals, the very low concentrations found in some foods are generally within established safety levels. Environmental pollution by slowly degraded pesticides such as DDT, a result of past agricultural practices, can lead to food chain bioaccumulation and to persistent residues in body fat. Such residues have been suggested as a possible risk factor for breast cancer; concentrations in tissue are low, however, and the evidence is not conclusive. Continued research regarding pesticide use is essential for maximum food safety, improved food production through alternative pest control methods, and reduced pollution of the environment. At the same time, banning any man-made chemicals with carcinogenic potential (as required for processed foods under the 1958 Delaney Amendment of the Food and Drug Act) is unrealistic, given the very low concentrations involved and the value of pesticides in sustaining our food supply. Scientists and consumer groups stress the important health benefits of a diet which includes many fruits and vegetables in contrast to the minimal risks associated with pesticide residues. 3. Toxic wastes. Toxic wastes in dump sites can threaten R&S145016 20 CANCER FACTS 4 FIGURES 1995