1. Cancer
Chapter 16

2. Introduction Causes about 565,000 deaths in the U.S. each year
1500 per day
Leading cause of disease related death among people under age 65.
Second most common cause of death
Evidence supports that most cancers could be prevented by simple lifestyle changes.
Tobacco is responsible for about 30% of all cancer deaths.
Poor diet and exercise habits account for another 30% of cancer deaths

3. Figure 16-1 Percentage of all cancer deaths linked to risk factors

4. What is Cancer?
Definition: an abnormal and uncontrollable multiplication of cells or tissue that can lead to death.
Tumor: a mass of tissue that serves no purpose.
Benign versus malignant tumors
Benign tumor: mass of cells enclosed in a membrane that prevents their penetration of other tissues.
Malignant tumor: (Neoplasm) cancerous, can invade surrounding tissues.
Every case of cancer begins as a change in a cell that allows it to grow and divide when it should not.

5. Figure 16-2 Tumor development occurs in stages

6. Metastasis Primary tumor
Definition: the spreading of cancer cells from one part of the body to another, occurs because cancer cells do not stick to each other as strongly as normal cells.
Metastasizing – the traveling and seeding process of cancerous cells
Cells break away from primary tumor and invade surrounding tissues or travel through the blood and lymphatic system.
New tumors are called
Secondary tumor or metastases

7. Types of Cancer Malignant Tumors
The behavior of tumors arising in different body organs is characteristic of the tissue of origin
Classified according to the types of cells.
Initially retain some of the original properties of the host cell.
Carcinomas - most common - arises from the epithelial tissue that cover body surfaces. Linings, tubes, cavities and secretion glands.

8. Types of Cancer Malignant Tumors
Sarcomas: arise in connective and fibrous tissues. Bone, muscle, cartilage and membranes covering muscle or fat.
Lymphomas: Cancers of the lymph nodes.
Leukemia: cancer of the blood-forming cells in bone marrow.

9. Figure 16-3 Cancer cases and deaths by site and sex

10. The Incidence of Cancer
1.4 million Americans are diagnosed yearly
American Cancer Society
Estimates that the 5-year survival rate for all cancers diagnosed between 1996 and 2003 is 66%
1 in 2 men and 1 in 3 women will be develop cancer during their lifetime.

11. The Incidence of Cancer
Since 1991 the death rate has dropped 18% in men and 10% in women
Prevention
Early detection
Improved therapy
American Cancer Society estimates
90% of skin cancer could have be prevented
87% of lung cancer could have be prevented
Regular screening and self-examinations could save an additional 100,000 lives per year.
About 10.8 million living Americans have a history of cancer.

12. Lung Cancer Most common cause of cancer death in the U.S.
162,000 deaths per year
Risk Factors
Tobacco smoking contributes to 87%.
Combined with environmental carcinogens multiply by a factor of 10.
Detection and Treatment (Difficult to detect)
Symptoms are not detected until cancer has reached the invasive stage.
Persistent cough, chest pain, or recurring bronchitis.
Diagnosis - chest x-ray or sputum examination - fiber-optic bronchosectomy.

13. Lung Cancer Treatment: Difficult to treat.
Caught early treated by surgery
Only 16% are detected prior to spreading
Radiation and chemotherapy are used in addition
Detected early 49% of patients are alive 5 years post.
Overall the survival rate is only 15%
Phototherapy, gene therapy, and immunotherapy are being studied.

14. Colon and Rectal Second leading cancer causing death. Risk Factors
Directly linked to diet and genetic predisposition.
90% occurs after 50 yr. of age.
Heredity
Lifestyle
Up to 1/3 of the population is genetically prone.
Detection and Treatment
Diet low in fat and High in fiber
Screening
Sigmoidoscopy or colonoscopy
Examine for polyps
Surgery is primary treatment
Radiation and chemotherapy used prior to surgery

15. Breast Cancer Most common cancer in women
Causes almost as many deaths in women as lung cancer
1:7 American women will develop it during her lifetime (182,000).
1:30 Will die from the disease (41,000 deaths).
Risk Factors
Most common in women over 50
“Disease of Civilization”
Common causes: Genetic predisposition, High fat, High calorie diet and Sedentary lifestyle, Alcohol use, early onset of menstruation, First child after 30 and obesity
Current use of Hormone Replacement Therapy (HRT)
Estrogen -cancer in estrogen-responsive sites

16. Breast Cancer Detection and Treatment Early detection. Treatment
Monthly breast self-exam for all women over 20.
Clinical breast exam by a physician every 3 yr.
Mammography- Every 1-2 years yr. old.
Over 50 every year.
Digital Mammography
Ultrasonography
Treatment
Biopsied
Survival rate
98% if the cells did not metastasized
89% for all stages at 5 years
80% at 10 years
New strategies for treatment and prevention

17. Prostate Cancer Most common cancer in men.
Second leading cancer death in men
186,000 new cases per year
More than 28,000 deaths per year
Risk Factors
Age
Diet
Lifestyle
Genetic predisposition
Early detection is key.
Prostate-specific antigen (PSA) blood test
Digital rectal exam
Ultrasound
Treatment
surgical removal of the prostate and radiation
Survival
All stages near 100% after 5 years

18. Cancers of the Female Reproductive Tract
Cervical cancer - sexually transmitted.
Most cases stem from infection by the human papillomavirus (HPV)- transmitted by unprotected sex.
Group of about 100 related viruses
Women high in HPV 16 are at a high risk
Smoking
Infection by genital herpes
Cervical cancer most common in women in their 20’s and 30’s.
Factors: sexual intercourse before 18, multiple sex partners, cigarette smoking and low socioeconomic status.
Screening:
PAP Test
Cervical dysplasia
All sexually active women ages should be tested
Treatment
Surgery
Cryoscopic probe
Localized laser
Vaccination of girls as young as 9 and women through age 26

19. Cancers of the Female Reproductive Tract
Uterine, or Endometrial:
Occurs after 55
Risk factors similar to breast cancer
Determined by Pelvic Exam
Treatment is surgery
95% survivability after 5 years
Ovarian Cancer:
Difficult to detect and diagnosis, No warning signs
Family history or genetic factors
Determined
Pelvic Exam
Ultrasound of ovaries
Treatment is surgical removal of the ovaries, the fallopian tubes, and the uterus.
Radiation and Chemotherapy are sometimes used.
Survival rate after 5 years is 92% for localized tumor
Survival rate after 5 years for all stages is 45%

20. Skin Cancer Risk Factors Types: Prevention Detection and Treatment
Most common form
1 million cases per year
62,500 are melanoma
Most serious
Easily detected and highly curable
Risk Factors
Exposure to ultraviolet rays during childhood
Common cause - sunburns and suntans
Caucasians are 10X more likely than African Americans to develop melanoma
Types:
Basal and Squamous
Melanoma - more dangerous form
Prevention
Avoid long term overexposure to sunlight
Blistering and peeling sunburns
Detection and Treatment
ABCD screen test

21. Figure 16-4 The ABCD test for melanoma

22. Other Cancers Oral Cancer Testicular Cancer Pancreatic Cancer
Lip, tongue, mouth, and throat
Smoking and tobacco use
Testicular Cancer
Rare
Most common n men age 20-35
Pancreatic Cancer
3 out of 10 are linked to smoking
Stomach Cancer
Twice as common in males
Infected by Helicobacter pylori
Bladder Cancer
Three times more likely in males
Smoking is the key risk factor
Kidney Cancer
Smoking and obesity are mild risk factors
Brain Cancer
Develops for no apparent reason

23. Leukemia Cancers of the white blood cells.
Starts in the bone marrow but spread to the lymph nodes, spleen, liver, other organs and CNS.
Abnormal production of immature white blood cells; rapidly growing cells displace red blood cell precursors
Immature WBC’s cannot fight off infections
Risk factors are unknown
20% of cases of adult leukemia are related to smoking
About 44,000 new cases and 22,ooo deaths each year.

24. Common Cancers Lymphoma Multiple Myeloma Arising from the lymph cells
Hodgkin’s disease
Non-Hodgkin’s disease (NHL)
More common
More deadly (6th most common cancer)
Risk factors are not well understood
Compromised immune system are at a greater risk
Multiple Myeloma
Malignant plasma cells produce tumors in the bone marrow.
Leads to anemia, excessive bleeding and decreased resistance to infection
Age is most significant risk factor – average age is 70

25. The Cause of Cancer The Role of DNA (Deoxyribonucleic acid)
Each cells has 23 pairs of chromosomes
Each controls the way a cell will work
Each rung is made up of four different nucleotide bases:
Adenine, thymine, cytosine and guanine
A gene – smaller unit of DNA
DNA Mutations and Cancer
Changes the way the cells function
Mutagens – radiation, certain viruses and chemical substances
Oncogenes – a gene involved in the transformation of a normal cell into cancer
Tumor suppressor genes – type of oncogene that restrains cellular growth
Hereditary Cancer Risks

26. Promoters Cancer promoters Cancer initiators:
Do not directly produce mutations, they accelerate the growth of cells without damaging of permanently altering the DNA.
Estrogen
Cancer initiators:
Carcinogenic agents
UV radiation
Cigarette smoking is a complete carcinogen because it is a cancer initiator and promoter.

27. Dietary Factors
Your food choices affect your cancer risk by exposing you to potential dangerous compounds and depriving you protective ones.
Dietary Fat and Meat
American Cancer Society encourages everyone to limit their consumption of processed and red meats.
Contributes to certain cancers:
Colon, stomach, and prostate
Alcohol
Fried Foods
Dietary Fiber
Fruits and Vegetables
Anticarcinogens
Carotenoids
Antioxidants versus Free radicals
Phytochemicals
Sulforaphane

28. Table 12-1 Food with Phytochemicals

29. Inactivity and Obesity
Linked to breast and colon cancer.
Benefits of Physical Activity
Speeding the movement of food through the digestive system
Strengthen the immune system
Decreasing blood fat levels
Prevention of obesity

30. Microbes About 15% of the world’s cancers are caused by microbes
Viruses
Human papillomavirus – cervical cancer
Bacteria
Helicobacter pylori – stomach cancer
Epstein-Barr virus (mononucleosis) – Hodgkin’s disease, cancer of the pharynx and some stomach cancers
Human herpesvirus 8 – Kaposi’s sarcoma and certain types of lymphomia
Hepatitis B and C – cause as many as 80% of the world’s liver cancers.
Parasites

31. Carcinogens in the Environment
Ingested Chemicals
Nitrosamines – Nitrates and nitrites combining with dietary substances - highly potent carcinogen
Environmental and Industrial pollution
Radiation - UV rays or man made

32. Detecting,Diagnosing, and Treating Cancer
Self-monitoring
CAUTION acronym
Diagnosing:
Biopsy
Magnetic resonance imaging (MRI)
Computed tomography (CT)
Ultrasonography
Treatment:
Surgery
Chemotherapy
Radiation Therapy
New and Experimental:
Gene therapy
Bone marrow and Stem Cell transplants
Biological therapies
Proteasome inhibitors
Anti-angiogenesis drugs
Enzyme activators/blockers

33. Figure 16-8 The seven major warning signs of cancer

34. Living with Cancer More than 10 million cancer survivors in the U.S.
Economic prejudice
Face prejudice from health insurers
Refuse to issue
renewal
Financial impact
Psychological support is important

35. Preventing Cancer
Lifestyle choices
Avoid tobacco
Controlling diet and weight
Regular exercise
Protecting skin from the sun
Avoiding environmental and occupational carcinogens Recommended screening tests
Follow the American Cancer Society’s recommendations.
Appropriate timing and methods for screenings
Be aware of the early signs and symptoms

36. Cancer
Chapter 16