1. Cancer Ray M. Merrill, PhD, MPH Department of Health Science
Brigham Young University

2. Did you know? In the United States…
1 in 3 people will develop cancer in their lifetime
1 in 8 women will develop breast cancer in their lifetime
1 in 6 men will develop prostate cancer in their lifetime
Over 1,400,000 people will be diagnosed with cancer this year
Over 550,000 people will die from cancer this year

3. Cancer 553,888 23.1 185.8 Fifteen Leading Causes of Death, US, 2004
Percent (%) of Total Deaths
Rank
Cause of Death
Number of Deaths
Death Rate* 1
Heart diseases
652,486
27.2
217.0 2
Cancer
553,888
23.1
185.8 3
Cerebrovascular diseases
150,074
6.3
50.0 4
Chronic lower respiratory diseases
121,987
5.1
41.1 5
Accidents (unintentional injuries)
112,012
4.7
37.7 6
Diabetes mellitus
73,138
3.1
24.5 7
Alzheimer disease
65,965
2.8
21.8 8
Influenza & pneumonia
59,664
2.5
19.8 9
Nephritis, nephrotic syndrome, & nephrosis
42,480
1.8
14.2 10
Septicemia
33,373
1.4
11.2 11
Intentional self-harm (suicide)
32,439
10.9 12
Chronic liver disease & cirrhosis
27,013
1.1
9.0 13
Hypertension & hypertensive renal disease
23,076
1.0
7.7 14
Parkinson disease
17,989
0.8
6.1 15
Assault (homocide)
17,357
0.7
5.9
All other & ill-defined causes
414,674
17.3
*Rates are per 100,000 population and age-adjusted to the 2000 US standard population.
Source: US Mortality Public Use Data Tape, 2004, National Center for Health Statistics, Centers for Disease Control and Prevention, 2006.

4. What is cancer?
Cancer is a collective name that refers to a group of many diseases with one common characteristic: uncontrolled cell growth or loss of the cell's ability to perform apoptosis (cell suicide).
Mutations occur to genes that control the normal process of cell growth and death
Gradual increase in the number of uncontrolled dividing cells
Mass of tissue occurs called a “tumor” (also called a neoplasm)

5. Development of Cancer from genetically altered cell to metastasis

6. Why do mutations happen?
Some cancer-causing mutations are simply spontaneous errors that appear in normal DNA molecules when cells duplicate their DNA prior to cell division
Some are related to environmental factors/exposures, diet, lifestyle choices or heredity (a few “suseptibility genes” passed down)

7. Accumulation of mutations in these 3 areas=cancer
The mutations that contribute to the development of cancer affect three general classes of gene:
Oncogenes
Tumor suppressor genes
DNA repair genes

8. Cancer Tends to Involve Multiple Mutations
The formation of cancer usually requires multiple mutations, with the chance increasing for mutations to accumulate and cancer to develop with more years of life (Doll & Peto, 1981).

9. Heredity and Cancer
Cancer is not considered an inherited illness since 80 to 90 percent occur in people with no family history of the disease
E.g., only about 5 percent of breast cancers are thought to be due to inheritance of particular form(s) of a "breast cancer susceptibility gene."

10. Different Kinds of Cancer
Carcinomas
Most common types of cancer
Arise from the cells that cover external and internal body surfaces Lung, breast, prostate, and colon are the most frequent cancers of this type in the United States
Sarcomas
Arise from cells found in the supporting tissues of the body such as bone, cartilage, fat, connective tissue, and muscle
Lymphomas
Arise in the lymph nodes and tissues of the body's immune system
Leukemias
Cancers of the immature blood cells that grow in the bone marrow and tend to accumulate in large numbers in the bloodstream

13. Tumor Grading/Staging
Microscopic examination also provides information regarding the likely behavior of a tumor and its responsiveness to treatment.
A low number grade (grade I or II) refers to cancers with fewer cell abnormalities than those with higher numbers (grade III, IV).

14. Tumor Grading/Staging
Based on the answers to the following questions, the cancer is assigned a "stage."
1. How large is the tumor, and how far has it invaded into surrounding tissues?
2. Have cancer cells spread to regional lymph nodes?
3. Has the cancer spread (metastasized) to other regions of the body?

15. Why Cancer Is Potentially Dangerous
A malignant tumor, a "cancer," is a more serious health problem than a benign tumor because cancer cells can spread to distant parts of the body.

16. Cancer Detection and Diagnosis
Early detection affects the outcome of the cancer
When cancer is found (type and how fast it is growing)
Invasion
Metastasized

17. Early Cancer May Not Have Any Symptoms
Screening methods are designed to check for cancer in people with no symptoms. Some examples of screening methods are:
Pap Test/smear
Mammograms
Blood Tests (PSA)
Fecal Occult Blood Test (FOBT)

18. Diagnose the presence of cancer
Screening tests indicate the possible existence of cancer, a doctor must then perform a biopsy
For leukemias, a small blood sample serves the same purpose
Microscopic examination will tell the doctor whether a tumor is actually present and, if so, whether it is malignant (i.e., cancer) or benign.

19. Tumor grade and stage are related to cancer survival

20. What Causes Cancer?

21. Heredity? Behaviors? Other Factors?
In theory, differences in heredity or environmental risk factors might be responsible for the different cancer rates observed in different countries.

22. Tobacco Use and Cancer Cigarette smoking linked with cancer of the:
lung
Mouth
Larynx
Esophagus
Stomach
Pancreas
Kidney
Bladder
Cervix
Current estimates suggest that smoking cigarettes is responsible for at least one out of every three cancer deaths.

24. Smoking-Related Cancers Relative Risks
Ex-smoker Current Smoker
Lip & Oropharangyeal
Oesophageal
Stomach
Anal
Pancreatic
Laryngeal
Lung M M
5.07 W F
Cervix
Vulvar
Penile
Bladder
Renal Parenchymal
Renal Pelvic
Source: Single et al., Am J Public Health 1999;89:

25. Low-Strength Radiation
Some atoms give off radiation, which is energy that travels through space. Prolonged or repeated exposure to certain types of radiation can cause cancer.

26. High-Strength Radiation
X-rays or radiation emitted from unstable atoms called radioisotopes
Stronger than ultraviolet radiation
Can penetrate through clothing and skin and into the body
High-strength radiation can cause cancers of internal body tissues

27. Examples of Human Cancer Viruses

28. Viruses A few viruses also can trigger the development of cancer
Cannot reproduce on their own
Viruses are small infectious agents
Enter into living cells and cause the infected cell to produce more copies of the virus
Causes the cell to become malignant

29. Bacteria and Stomach Cancer
The bacterium H. pylori, which can cause stomach ulcers, has been associated with the development of stomach cancer

30. Breast cancer risk factors
Most common cancer in women and second to lung cancer in the number of cancer deaths among women
Causes/risk factors
Heredity
Long-term exposure to high blood levels of estrogen
Early onset of menstruation
Late onset of menopause
No children or first child after age 30
Obesity
Current use of HRT
Alcohol use
Inactivity
Diet low in vegetables and fiber

31. Prostate Cancer Risk Factors
Age
Race (African American=higher)
Diet: high in calories
Male Hormones
Environmental Exposures
A Vasectomy, BPH, STD’s
Family History of Prostate Cancer

32. Cancer Risk and Aging

33. Summary of What Causes Cancer Source: CDC
Sexual Factors
Alcohol Overuse
Environmental &
Occupational
Factors
Tobacco Use
Other Factors
Diet & Physical
Activity

34. Ways to prevent cancer:
Maintain a healthy weight;
Eat no more than two or three servings of red meat per week;
Take a multivitamin with folate every day;
Drink less than one alcoholic drink a day;
Eat five or more servings of fruits and vegetables per day;
Eat more high fiber foods such as whole grains, wheat cereals, bread, and pasta;
Include cruciferous vegetables in your diet (such as broccoli, cabbage, etc.);
Do not smoke;
Protect yourself from the sun;
Avoid certain workplace exposures;
Protect yourself and your partner(s) from sexually transmitted infections; and
Exercise regularly.

35. Quick Quiz 3pts/ques 1. What is the most common cancer for men, women?
2. Give 3 risk factors for the most prevalent male cancer
3. Give 3 risk factors for the most prevalent female cancer
4. What is the common characteristic that makes cells result in cancerous growth?

36. Quick Quiz cont.
5. What are the four main categories/kinds of cancer and describe what type of tissue that each arises from.
6. Compare benign vs malignant
7.Using no more than 5 sentences, describe how a genetically altered cell becomes cancer that has spread throughout the body
8. Describe the I-IV grading/staging system for cancer

37. Quick Quiz, cont
9. How and to what extent does genetics play in the development of cancer?
10. List 3 ways cancers can be prevented