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Chapter Sixteen
Cancer
Cancer
Cell regulation problem causing
abnormal cell growth
• Most cancers take the form of tumors: a
mass of tissues that serve no physiological
purpose
• Benign: cells similar to surrounding normal cells and
are enclosed in a membrane that prevents them from
penetrating neighboring tissues
• Malignant: capable of invading surrounding
structures, producing invasive tumors or uncontrolled
growth
How Cancer Spreads: Metastasis
• Metastasis is the spreading of cancer cells which
occurs due to the lack of cellular cohesiveness
• They break away and pass through the lining of
lymph or blood vessels to invade nearby tissues
• These new tumors are called secondary tumors
or metastases
Types of Cancer
• Carcinomas – Arise from epithelia, tissues that cover
external body surfaces (organs, skin, nerves,
membranes)
• Sarcomas – bone, blood, connective tissue
• Lymphomas – immune tissues/system
• Leukemia - blood and blood forming tissues (bone
marrow)
The Incidence of Cancer
• Each year, 1.4 million people in the United
States are diagnosed with cancer
• Cancer death rates have dropped more than
10% since 1990
• The American Cancer Society believes that
thousands of cases of colon, breast, and uterine
cancer could be prevented by lifestyle changes
Lung Cancer
• Risk Factors
– Smoking
– Environmental pollutants
• Prevention
– Remove smoke element
• Treatment
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Surgery
Radiation
Chemotherapy
Medications
Full recovery remains unlikely in all but a small percentages of cases
Colon and Rectal Cancer
• Considered the second leading cause of cancer deaths
(could arise from pre-existing polyps)
• Risk Factors
• Age
• Heredity
• Lifestyle factors
• Detection and Treatment
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Removal of polyps
Yearly stool blood test
Sigmoidoscopy/colonoscopy
Surgery
Breast Cancer
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Most common cancer in Women
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Risk factors
– Early menstrual cycle for women
– Women with no children or having children later in life
– Hormone replacement therapy use
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Prevention
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Diet
Mammography
Activity levels
Pregnancy and breastfeeding decisions
Occupational hazards
New medications
Treatment
– Lumpectomy
– Drug therapy
– Chemotherapy/radiation treatments
Prostate Cancer
• Most common cancer in Men
• Risk factors
– Age, dietary fat intake, genetic link
• Prevention
– Dietary intake of Vitamin E and selenium, drug therapy
• Early Detection
– PSA screenings, ultrasound rectal exam
• Treatment
– Surgery, radiation, implantation of radioactive seeds
Cervical Cancer
• Risk factors
– HPV infection
– Smoking and socioeconomic factors
• Prevention
– Sexual abstinence
– Pap tests
– Careful selection of sexual partners
• Treatment
– Surgery (minor or major)
– Radiation/chemotherapy
Uterine Cancer
• Risk Factors
– Early menarche, late menopause, lack of ovulation, never
having given birth, ERT, use of tamoxifen, and also in
diabetics, obese, and hypertensive women
• Prevention
– Minimize high levels of estrogen and regular physician care
• Treatment
– Surgery, radiation, chemotherapy, hormone treatment
Ovarian Cancer
• Prevention
– Similar to what is recommended for breast cancer
– Prophylactic oophorectomy
• Early Detection
– Referred as the “silent cancer”
• Annual pelvic exams
• Genetic screenings
• Treatment
– Surgery
– Chemotherapy
– Drug therapy
Skin Cancer
• Considered the most common cancer of all
• Risk factors
– Severe sunburn during childhood, chronic sun exposure
during young adulthood (UV)
• Prevention
– Reduce exposure to sun’s rays, use sunscreens,
• Early Detection
– Recognition and early diagnosis
• Treatment
– Surgery, chemotherapy, interleukin-2
Skin Cancer
• Risk factors
– Severe sunburn during childhood, chronic sun exposure
during young adulthood
• Prevention
– Reduce exposure to sun’s rays, use sunscreens,
• Early Detection
– American Cancer Society guidelines (next slide)
• Treatment
– Surgery, chemotherapy, interleukin-2
Testicular Cancer
• Risk factors
– Family history, environmental factors
• Prevention
– Self exams
• Early Detection
– Observations and self exams
• Treatment
– Surgery, chemotherapy, radiation
Other Cancers
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Pancreatic Cancer
Stomach Cancer
Bladder Cancer
Kidney Cancer
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Brain Cancer
Leukemia
Lymphoma
Multiple Myeloma
The Causes of Cancer
• The Role of DNA
• Role of inheritance of
certain genes
• DNA mutations such as
oncogenes
• Cancer promoters
• Dietary Factors
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Dietary Fat and Meat
Alcohol
Fiber intake
Fruits and Vegetables
• Inactivity and Obesity
• Microbes
• Carcinogens in the
Environment
• Ingested chemicals
• Industrial pollution
• Radiation
Detecting Cancer
(Figure 16-5)
Identify the 7 warning signs of cancer
Change in bowel/bladder habits
A sore that does not heal
Unusual bleeding or discharge
Thickening of tissues (schlerotic change)
Indigestion or difficulty swallowing
Obvious change in a wart/mole
Nagging cough
Diagnosing Cancer
• Detection begins with a physical exam
• Exploratory surgery or a biopsy may be
performed to identify a cancer’s stage or the
following:
• MRI
• CT
• Ultrasonography have been used to view tumors
and is considered completely safe
Treating Cancer
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Surgery
Chemotherapy
Radiation
New Experimental Techniques such as:
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Gene therapy
Bone marrow and stem cell transplants
Biological Therapies
Protease inhibitors
Anti-angiogenesis drugs
Telomerase inhibitors
Preventive Cancer
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Avoiding Tobacco
Controlling Diet and Weight
Regular Exercise
Protecting Skin from the Sun
Avoiding Environmental and Occupational Carcinogens
Having regular screening exams
Chapter Sixteen
Cancer