1.3c Neoplastic Flashcards
Cancer what is it?
Group of complex diseases
Can affect any body tissue
Occurs when normal cells mutate into abnormal cells with uncontrolled growth
Chronic disease with acute episodes
Oncology
- Study of cancer
- Derived from Greek oncoma, meaning “bulk”
Oncologists
Oncology nurse
Neoplasms what is it?
Neoplasm
-Mass of new tissue that grows independently of its surrounding structures and has no physiologic purpose
-Used interchangeably with “tumor”
Benign neoplasms
what is it?
Local Cohesive Well defied borders Pushes other tissue out of the way Slow growth Encapsulated Easily removed Usually dos not recur
Malignant neoplasms
what is it
Invasive Non-cohesive Does not stop at tissue borderers Invades and destroys surrounding tissues Rapid growth Metastasized to distant sites Not always easy to remove Can recur
Characteristics of Malignant Cells
Loss of regulation of the rate of mitosis
Loss of specialization and differentiation
Loss of contact inhibition
Progressive acquisition of a cancerous phenotype
Irreversibility
Altered cell structure
Simplified metabolic activities
Transplantability (metastasis)
Ability to promote its own survival
Risk Factors for Cancer
1 of 3
Genetics and heredity
- Recurring patterns of cancer within a family a risk factor for heredity, not necessarily genetic
- Familial cancers generally occur during old age.
Age
- Associated with aging
- Hormonal changes
Gender
- Breast, thyroid cancer in women
- Prostate, bladder cancer in men
Poverty
-Higher risk due to lack of insurance and access to care
Stress
-Risk if continuous and unmanaged
Risk Factors for Cancer
2 of 3
Diet
-High in red meat, saturated fat
Occupation
-Standards to protect workers from hazardous substances may not be strict enough
Infection
-Hepatitis B, C, HPV
Obesity
- Hormone-dependent cancers
- Breast, colon, endometrium, kidney, adenocarcinoma of esophagus
Sun exposure
- Ozone layer thinning
- Older adults with decreased pigment are more at risk, regardless of skin color.
Risk Factors for Cancer
3 of 3
Tobacco use
- Most preventable cause of death
- Lung cancer
- Secondhand smoke (SHS)
Alcohol use
Recreational drug use
- Promotes unhealthy lifestyle
- Marijuana demonstrative, but not implicated
Cellular Differentiation
Hyperplasia
-Increase in number, density of normal cells
Metaplasia
- Change in normal pattern of differentiation
- Cell types not normally found in that location of the body
Dysplasia
-Loss of DNA control over differentiation occurring in response to adverse conditions
Anaplasia
-Regression of a cell to immature or undifferentiated cell type
These types often reverse after irrigating factor is eliminated.
Theories of Carcinogenesis
Cell mutation
Cell mutation
Carcinogens cause mutations in cellular DNA and transform normal cells into cancer cells.
Three stages
-Initiation stage: initial incident that caused the damage (sunburn, radiation exposure), cells then become defective
- Promotion stage: occurs over many years, repeated exposure (sun)
- Progression stage: inherited changes in the cell causing cancer
Theories of Carcinogenesis
Oncogense
Oncogense: abnormal genes
- Promote cell proliferation
- Capable of triggering cancerous characteristics
- Proto-oncogenes: normal genes
- –Normal genes that promote growth and repair
Known Carcinogen Groups
Two groups
Two groups
Genotoxic
-Directly alter DNA and cause mutations.
Promoter substances
-Cause other adverse biologic effects (secondary physiological effects), hormone imbalance, chronic lung damage
Known Carcinogens
Viruses
Weaken immunologic defenses against neoplasms
HIV, hepatitis B, HPV
Known Carcinogens
Drugs and hormones
Impair immune function
Estrogen-containing contraceptive pills implicated in breast cancer but reduce ovarian cancer.
Known Carcinogens
Chemical agents
Chemical agents
Both genotoxic and promotional
Natural substances in the body
-Bile acids from a high-fat diet
Some foods: sugar substitutes, nitrate preservatives
Known Carcinogens
Physical agents
Physical agents
Excessive exposure to radiation
Radon
Tumor Invasion
Invasion
Qualities of aggressive tumors to facilitate invasion
- Ability to cause pressure atrophy
- Ability to disrupt basement membrane
- Motility
- Response to chemical signals from adjacent tissues. Chemotaxis: move around and respond to chemical responses
Tumor Metastasis
Metastasis
- Occurs by means of one or more mechanisms or spread by way of body cavities
- Blood- or lymph-borne metastasis
- Metastatic lesions
- Cells escape detection by immune system.
Most common metastasis sites: lymph nodes, liver, lungs, bones, brain
Physiologic and Psychologic Effects of Cancer
- Functional
- Infection
- Blood
- Malaise or fatigue
- Anorexia, nausea, vomiting
- Pain
- Grief, Fear, Punishment, Isolation, Disturbed Body Image and Sexual Dysfunction
Diagnosis of Cancer
X-ray imaging Computed Tomography Magnetic Resonance Imaging Ultrasonography Tissue samples through biopsy Collections of secretions Simple screening procedures Tumor markers
Classification
Tissue origin?
Benign?
Malignant?
Epithelium
Benign: papilloma
Malignant: carcinoma
Melanocytes
Benign: melanoma
Malignant: malignant melanoma
Adipose tissue
Benign: lipoma
Malignant: lipocarcinoma
Neural tissue
Benign: ganglioneuroma
Malignant: neuroblastoma
Bone tissue
Benign: osteoma
Malignant: osteosarcoma
Granulocytes
Benign: granulocytosis
Malignant: leukemia
Grading of tumors
Grading
- Evaluates amount of differentiation (matured, most like parent cell) of cell and estimated growth rate
- Classification is on grade scale of 1 (least malignant) to 4 (aggressively malignant)
