CANCER
What Is Cancer?
ØCancer – a large group of diseases characterized by the uncontrolled growth and spread of abnormal cells
Neoplasm – new growth of tissue that serves no physiological function
Tumor – clumping of neoplasmic cells
Malignant - cancerous
Benign - noncancerous
Biopsy – microscopic examination of cell development
ØMetastasis – malignant tumors that are not enclosed in a protective capsule have the ability to spread to other organs
Mutant cells – disruption of RNA and DNA within normal cells may produce cells that differ in form, quality and function from the normal cell
•Cancerous cells divide repeatedly out of control even though they are not needed, they crowd out other normal cells and function abnormally. They can also destroy the correct functioning of major organs.
What Causes Cancer?
•Cancer arises from the mutation of a normal gene.
•Mutated genes that cause cancer are called oncogenes.
•It is thought that several mutations need to occur to give rise to cancer
•Cells that are old or not functioning properly normally self destruct and are replaced by new cells.
•However, cancerous cells do not self destruct and continue to divide rapidly producing millions of new cancerous cells.
•A factor which brings about a mutation is called a mutagen.
•A mutagen is mutagenic.
•Any agent that causes cancer is called a carcinogen and is described as carcinogenic.
So some mutagens are carcinogenic
Eternalnal Factors – chemicals, radiation, viruses, and lifestyle
Internal Factors – hormones, immune conditions, and inherited mutations
Theories
•Cellular change/mutation theories
•Carcinogens
•Oncogenes/ protooncogenes
Risks For Cancer
Lifetime risk – the probability that an individual, over the course of a lifetime, will develop cancer or die from it
Relative risk – measure of the strength of the relationship between risk factors and a particular cancer
Smoking – 30% of all cancer deaths, 87% of lung cancer deaths
Obesity – 50% higher risk for breast cancer in postmenopausal women, 40% higher risk in colon cancer for men
Biological Factors
ØSome cancers such as breast, stomach, colon, prostate, uterus, ovaries and lung appear to run in families
Hodgkin’s disease and certain leukemia's show similar patterns
University of Utah research suggests that a gene for breast cancer exists
A rare form of eye cancer appears to be transmitted genetically from mother to child
Reproductive And Hormonal Risks For Cancer
Pregnancy and oral contraceptives increase a woman’s chances of breast cancer
Late menarche, early menopause, early first childbirth, having many children have been shown to reduce risk of breast cancer
Occupational And Environmental Factors
Asbestos
Nickel
Chromate
Benzene
Arsenic
Radioactive substances
Cool tars
Herbicides/pesticides
Social And Psychological Factors
Stress has been implicated in increased susceptibility to several types of cancers
Sleep disturbances, diet, or a combination of factors may weaken the body’s immune system
Chemicals In Foods
Sodium nitrate when ingested forms a potential carcinogen, nitrosamine
Sodium nitrate is still used because it is effective in preventing botulism
Pesticide and herbicide residues
Viral Factors
Herpes-related viruses may be involved in the development of leukemia, Hodgkin’s disease, cervical cancer, and Burkitt’s lymphoma
Epstein-Barr virus, associated with mononucleosis, may contribute to cancer
Human papillomavirus (HPV), virus that causes genital warts, has been linked to cervical cancer
Helicobacter pylori causes ulcers which are a major factor in the development of stomach cancer
Medical Factors
Some medical treatments actually increase a person’s risk for cancer
Diethylstilbestrol (DES) used 1940 to 1960 to control bleeding during pregnancy, the daughters of mothers that used DES were found to have an increased risk for cancers of the reproductive organs
Estrogen supplementation
Chemotherapy used to treat one form of cancer may increase risk for another type of cancer
Types Of Cancers
ØClassification of cancers
•Carcinomas
•Sarcomas
•Lymphomas
•Leukemias
Lung Cancer
In 2006, 174,470 people died from lung cancer
Since 1987, more women have died from lung cancer that breast cancer
Symptoms: persistent cough, blood-streaked sputum, chest pain
Treatment: surgery, radiation therapy, and chemotherapy
Prevention: avoid smoking and environmental tobacco smoke
Breast Cancer
1 out of 8 women will develop breast cancer (lifetime risk)
1 in 227: birth to age 39
1 in 25: ages 40-59
1 in 15: ages 60-79
Detection: mammograms, regular breast self-exams
Symptoms: lump in the breast, thickening, dimpling, skin irritation, distortion or tenderness
Risk factors: family history, hyperplasia, long menstrual history, obesity after menopause, oral contraceptives
Treatment: lumpectomy, radical mastectomy, radiation, chemotherapy
Prevention: exercise
Colon And Rectal Cancers
ØThird most common cancer in men and women with over 148,610 new cases diagnosed in 2006
Risk factors: over 50 years old, obese, family history of colon or rectum cancer or polyps, diets high in fats, low in fiber, smoking, high alcohol consumption, lack of exerciseMore Colors...
90% of colorectal cancers are preventable
Treatment: radiation, surgery, and possible chemotherapy
Prevention: regular exercise, a diet heavy in fruits and plant-origin foods, a health weight, and moderation in alcohol consumption
Prostate Cancer
ØMost common cancer in American men, excluding skin cancer
ØIn 2006, 234,460 new cases diagnosed
Ø1 in 3 men will be diagnosed in their lifetime
Prostate is a muscular, walnut-sized gland the surrounds part of the urethra. Its primary function is to produce seminal fluid.
Symptoms: nonspecific, weak or interrupted urine flow, difficulty starting or stopping urination
Risk factors: age, race, nationality, family history, diet, lifestyle, and vasectomy
Prevention: diet high in lycopenes, vitamin E
Skin Cancer
Cancer-
Cancer starts out as a mutation in one gene in one cell. Then the mutated cell starts dividing rapidly and taking over the whole area.
CHARACTERISTICS OF CANCER CELLS
4. ANGIOGENESIS (INDUCE BLOOD VESSEL FORMATION)
5. METASTASIZE
ORIGIN
MUTAGEN is an agent that increases chances of DNA change or mutation. Everyone exposed for long enough will get DNA mutations, and possibly cancer. Examples are x-rays and some medicines (thalidimide; caused birth defects
1. CARCINOGENS
2. HEREDITY
DIAGNOSTIC PROCEDURES
Particular types of cancers run in families, such as breast, lung, and colon cancer
The American Cancer Society says the following are signs of cancer: C-A-U-T-I-O-N
1. BEHAVIORS
2. DIET
PREVENTION OF SKIN CANCER:
1. RADIATION
2. CHEMOTHERAPY
3. BONE MARROW TRANSPLANTS
4. IMMUNOTHERAPY
5. GENE THERAPY
6. COMPLEMENTARY THERAPIES
Long term effects of sun exposure can result in skin cancer
Malignant melanoma, deadliest form of skin cancer
Sun give off 3 types of harmful rays:
•UVA
•UVB
•UVC
Prevention: limit exposure to harmful UV rays, drink more fluids than usual, apply cool compresses to skin, moisturize skin
What to look for – The ABCD rule
•Asymmetry – half of mole does not look like the other half
•Border irregularity – the edges are uneven
•Color – pigmentation is not uniform
•Diameter – greater than 6mm
Ovarian Cancer
ØFifth leading cause of cancer death for women, 20,180 new cases diagnosed reported in 2006
ØMost common symptom is enlargement of the abdomen
ØRisk factors include: family history, age, childbearing, cancer history, fertility drugs, talc use in genital area, genetic predisposition
ØPrevention: diet high in vegetables and low in fat, exercise, sleep, stress management, and weight control
Cervical and Endometrial (Uterine) Cancer
9,710 new cases of cervical cancer, 41,200 cases of endometrial cancer in U.S. in 2006
Pap test – cells are taken from the cervical region
Risk factors:
•Cervical cancer: early age at first intercourse, multiple sex partners, cigarette smoking, and certain STIs
•Endometrial cancer: age, endometrial hyperplasia, overweight, diabetes, and high blood pressure
Other Cancers
ØPancreatic cancer – “silent” 4% 5-year survival rate
ØLeukemia – cancer of blood forming tissues
Detecting Cancer
ØThe earlier the diagnosis the better the prospect for survival
ØMagnetic resonance imaging (MRI)
ØComputerized axial tomography scan (CAT scan)
ØProstatic ultrasound
ØRegular self-exams, and check ups
New Hope In Cancer Treatments
Remove less surrounding tissue during surgery
Combine surgery with radiation or chemotherapy
Immunotherapy
Cancer-fighting vaccines
Gene therapy
Neoadjuvant chemotherapy
Stem cell research
nucleus of every one of the human body's 30 trillion cells exists DNA, the substance that contains the information needed to make and control every cell within the body. Here is a close-up view of a tiny fragment of DNA.
•Early diagnosis can often make a difference to how easily cancer is managed/treated and the chance of making of good recovery.weeks
Know Your Body and What is Normal for You
•If it turns out not to be serious, you’ve got peace of mind
•; if you smoke, stop doing so. If you fail to stop, do not smoke in the presence of non-smokers.
2)Avoid ObesityUndertake some brisk, physical activity Increase your daily intake and variety of vegetables and fruitsIf you drink alcohol, whether beer, wine or spirits, moderate your consumption Care must be taken to avoid excessive sun exposure.
Food, nutrition and physical activity and the prevention of cancer
•Be physically active every day
•Eat mostly foods of plant origin
•Red meat
–Alcohol salt
•Add dietary supplements for cancer prevention
•Breastfeed children for at least six months
© 2018 health . All Rights Reserved | Design by GITSYS