Transcript Powerpoint

Cancer and AIDS
What is cancer?
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Rapid reproduction of irregular cells
forming a neoplasm (tumor)
Results from a dysfunction in the cell’s
DNA
Tumor cells reproduce at different rates,
doubling times ranging from 23 to 209
days.
Four Types of Cancer
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Carcinomas 
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Lymphomas –
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Cancer of the lymphatic system
Sarcomas
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Malignant neoplasms of the skin and organ cells. About
85% of all cancers.
Malignant neoplasms of the muscle, bone or connective
tissue
Leukemias
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Cancers of the blood forming organs (e.g., bone marrow)
leading to proliferation of white blood cells.
Cancer
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Metastasis – migration of cancer cells to
other parts of the body.
Metastases – new neoplasms formed after
metastasis.
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50% of people will live 5 or more years after
diagnosis and most of these will be cured.
Cancer death rates increasing, primarily due to
increases in lung cancer.
Effects
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Proliferation of cancer cells at each site
interferes with normal cell development and
functioning.
Produces pain as it creates pressure on
tissues and nerves and blocks flow of body
fluids.
Most experience severe pain in later stages.
How does cancer cause
death?
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Direct by spreading to a vital organ and
takes nutrients the organ needs causing the
organ to fail.
Indirect by weakening the victim, impairing
appetite and immune functioning.
Cancer Prognosis and Causes
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Prognosis depends on the site and on how
early the cancer was detected.
Causes involve an interplay of genetic and
environmental factors.
Cancer Genetics
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Genetics appear to play a role in some
cancers.
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Example - breast, colon, prostate, ovarian
However, environmental factors also run in
families (e.g., diet) and so family history of
cancer does not necessarily mean that the
cancer was due to genetic factors.
In some cases you can test your genes.
Cancer & Ethnicity
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Anglo men – higher rates of bladder cancer.
Hispanics – lowest rates of lung cancer but women
have highest rates of cervix cancer.
Blacks – highest rates of prostate cancer.
Japanese – highest rates of stomach cancer.
Chinese Americans lowest rates of liver cancer.
Northern Europeans – high rates of breast cancer.
Environmental Factors
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Smoking
Diet
Radiation
Chemicals
Viral component in some cancers.
Age, Gender, and SocioCultural Factors
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Risk increases with age, especially after
middle age.
Gender differences in types of cancers.
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Breast cancer more common in women
Blacks and whites have higher rates than
other ethnic groups.
Blacks more likely to die with cancer
because it tends to get detected later.
Diagnosing and Treating
Cancer
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Physician tests for breast, colon,
prostate, skin, testes, cervix.
Self-administered testing for some
cancers – breast, skin, testes.
CAUTION – Warning Signs of
Cancer
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Change in bowel or bladder habits.
A sore that does not heal.
Unusual bleeding or discharge.
Thickening or lump in the breast or
elsewhere.
Indigestion or difficulty swallowing.
Obvious change in wart or mole.
Nagging cough or hoarseness.
Diagnostic Procedures
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Blood or urine tests for abnormal levels of
hormones or enzymes.
Radiological imaging (X-ray, CT scan, MRI)
to look for tumors.
Biopsy – analysis of suspicious tissue.
Cancer Treatments
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Options depend on size, site(s), and quality
of life tissue.
Age often inappropriately affects treatment
choice with those over 60 receiving less
radiation and chemotherapy.
Cancer Treatment Options
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Surgery –
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If cancer is localized, can remove it.
If it has spread then surgery can remove large
portions to reduce symptoms.
Potentially healthy tissue is also sometimes
removed in case some cancer cells have
spread to the tissue.
Less tissue tends to be removed now than in
previous years (e.g., lumpectomy in stead of
mastectomy).
Cancer Treatment Options
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Radiation – alters body cells so they are
destroyed or cannot reproduce.
Two types:
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External beam therapy: beam of radiation
directed to malignant tissue (multiple
treatments).
Internal radiation therapy: place radioactive
substance inside body near tumor.
Microwave therapy - new
Radiation Side Effects
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Troubling side effects since healthy tissue
is effected as well
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Nausea, fatigue, burning, loss of appetite,
sterility, bowel/bladder dysfunction, reduced
bone marrow function.
Anxiety in anticipation of treatment.
Chemotherapy
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Oral or injection drugs targeted at cells that
reproduce rapidly.
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Works better for some forms of cancer (e.g.,
testicular, leukemia) than others (e.g., brain,
pancreatic).
Effects healthy cells that also divide rapidly
(e.g., bone marrow, mouth, intestinal tract,
hair follicles) leading to reduced immunity,
mouth soars, nausea, vomiting, hair loss, etc.
Chemotherapy Side-effects
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Side-effects may lead to discontinuation of
treatment.
Anticipatory nausea – classical conditioning
process whereby patients become
nauseous in anticipation of receiving
treatment. Occurs in ¼ to ½ of patients.
Chemotherapy Side-Effects
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Cancer treatment is aversive, complex,
demanding, and requires many lifestyle
changes.
Adherence is good among most adults,
but not for minority and lower class
individuals or adolescents.
Psychosocial Impact
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“Real killer” and it is associated with pain,
disability, and disfigurement.
Threat of remission – fear.
Treatment is aversive.
Prognosis is poorer for those who do not
cope well.
Most adapt well – most difficult in early
months or when symptoms worsen or recur,
or with disability and pain.
AIDS
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Acquired immune deficiency syndrome
New and infectious
Worldwide, the majority of HIV+ are
heterosexual non-drug users.
HIV – human immunodeficiency virus
(attacks the immune system, notably the
helper T cells and macrophages).
HIV+ can be asymptomatic for years.
AIDS – Risk Factors
Three main routes for infection
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Sexual activity involving the exchange of
body fluids.
Sharing contaminated needles.
Birth by infected mother.
Incidence is increasing particularly among
heterosexuals.
Age, Gender, and SocioCultural Factors
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Highest rates among 20-45 year olds.
2-3 times higher in men.
Disease progresses more rapidly among
older people.
Death rate higher for Blacks.
Highest rates of infection in Africa,
Southeast Asia, and South America.
From HIV Infection to AIDS:
Four Stages of Progression
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Mild symptoms like those of other diseases (e.g.,
soar throat, fever, rash, headache). Lasts 1-8
weeks.
Latent period for as long as 10 years with no or
few symptoms.
AIDS related complex – cluster of symptoms (e.g.,
swollen glands, loss of appetite, fever, fatigue,
night sweats, persistent diarrhea).
Severe immune impairment – multiple opportunist
infections (e.g., lungs, gastrointestinal tract).
What leads to these changes?
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Gradual decrease in T4 (CD4), helper tcells over many years.
In early stages virus “hides” in lymph
tissue and multiplies.
AIDS Diagnosis
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“AIDS” diagnosis after development of:
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Pneumocystis carinii pneumonia, Kaposi’s
sarcoma, or very low levels of CD4.
Viral load test: determines level of HIV in body.
Damage to part of the immune system that
fights viral infections – existing antibodies
usually still work.
HIV attaches to CD4 and replicates itself,
destroying the cells function.
Psychosocial Impact
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Others fear and blame them.
Rejected by others.
Concerned about who in their social
network they can tell.
Most adapt well, but those who don’t have
more rapid disease progression.
AIDS Treatment Options
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Hope for eventual vaccine – some success
in producing immunity in monkeys.
Protease inhibitors – New class of drugs
that interfere with maturity of HIV cells and
slows progression of disease.
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Don’t know the long term effects. They have
troubling side-effects are expensive, and
typically have to be taken in very tight
schedule.
AIDS Treatment Options Nutrition
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Wasting syndrome
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Extreme weight loss, muscle loss as well as
fat.
Important to keep up strength but tend
to loose appetite and have persistent
diarrhea.
AIDS Prevention
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Education is not enough – continue high
levels of risk behaviours.
Need new intervention strategies.
Risk may be linked to certain personality
characteristics.
Study by Trobst et al.
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Examined personality factors contributing to
risk behaviours in high risk groups.
Over 500 participants from substance abuse
centres, homeless shelters, etc.
Five-Factor Model of personality assessing:
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Neuroticism
 Agreeableness
Extraversion
 Conscientiousness
Openness to new experience
Study by Trobst et al.
Results
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HIV+ had higher N and lower C scores than
low risk groups.
Cause or consequence?
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High risk HIV- had higher N and lower C than
low risk group.
High neuroticism and low conscientiousness
appear to act as predisposing risk factors
leading to engagement in risky behaviours and
enhanced risk for contracting HIV.