Cancer Flashcards
(101 cards)
Cancer
large group of disorders with different causes, manifestations, treatments, and prognoses.
Most cancers occur in older adults.
78% of all cancer diagnoses are in people > 65 years. Incidence of overall cancer rate is higher in men than in women.
Second leading cause of death in the United States.
benign tumors / benign neoplasms
does not spread, can become malignant in some cases
- Margins of tumor are well defined
- Cell growth is local
- Cells are well-differentiated
- Relatively innocuous, doesn’t metastasize
- Slow rate of growth
malignant
has the potential to spread to other parts of the body.
- Margins are poorly defined
- Crab like appearance, hence the term cancer
- are invasive
- Neoplastic cells extend into and destroy surrounding tissue
- Cells are not well-differentiated
- Growth is erratic, slow to rapid
- Can metastasize
Cancer incidence
Men: prostate, lung, colorectal Women: breast, lung, colorectal
Overall cancer rate deaths has declined.
- However, cancer death rates in African-American men remain substantially higher than those among Caucasian men and twice those of Hispanic men
Characteristics of Normal Cells
- Have limited cell division
- Undergo apoptosis
- Show specific morphology
- Have a small nuclear-cytoplasmic ratio
- Perform specific differentiated functions
- Adhere tightly together
- Non-migratory
- Grow in an orderly and well-regulated manner
- Contact inhibited
- Euploid
Cancer pathophysiology
- Cancer is a disease process that begins when a cell is transformed by genetic mutations of the cellular DNA.
- Genetic mutations may be inherited and/or acquired, leading to abnormal cell behavior.
- The initial genetically altered cell forms a clone and begins to proliferate abnormally, evading growth-regulating signals as well as the immune system defense mechanisms of the body.
- Cells acquire a variety of capabilities that allow them to invade surrounding tissues and/or gain access to lymph and blood vessels, which carry the cells to other areas of the body (metastasis).
Characteristics of Cancer Cells
- Have rapid or continuous cell division
- Do not respond to signals for apoptosis
- Show anaplastic morphology
- Have a large nuclear-cytoplasmic ratio
- Lose some or all differentiated functions
- Adhere loosely together
- Able to migrate through embryonic cells
- Grow by invasion
- Are euploid(when a human cell has an extra set of 23 chromosomes) with 23 pairs of chromosomes
Cancer development
Initiation - occurs in genetic level, permits malignant transformation, DNA chain break, gene mutation activate proto-oncogenes
Promotion - cancer cell form tumor, promoting of agent beyond latency
Progression - cells show capacity to invade or metasize to surrounding tissues, tumor develops own blood supply, angiogenesis happen, TAF also happens
Metastasis - movement of cancer cell from primary to remote site, cells lose adherence property.
carcinogenesis
malignant transformation
Risk factors for cancer
- Viruses and bacteria
- Physical agents
- Chemicals
- Genetic or familial factors
- Lifestyle factors
- Hormones
Cancer viruses
Accounts for about 15% of worldwide cancer cases
- Retroviruses- t cell leukemia
- Papillomavirus- cervical cancer
- HIV-associated with Kaposi’s sarcoma
- Herpes virus- Epstein-Barr virus, Burkitt’s lymphoma
- Chronic hepatitis B- liver cancer
viruses and bacteria etiology
Viruses are thought to incorporate themselves in the genetic structure of cells, thus altering future generations of that cell population (perhaps leading to cancer).
Physical Agents:
Exposure to sunlight or radiation, chronic irritation or inflammation, tobacco carcinogens, industrial chemicals, and asbestos.
Chemical Agents:
Tobacco, chewing tobacco, and passive smoking.
Pesticides and formaldehydes; arsenic, soot, and tars; asbestos; wood dust; etc.
genetics and familial factors
Almost every cancer type has been shown to run in families.
May be due to genetics, shared environments, cultural or lifestyle factors.
Lifestyle factors for cancer
- Diet, obesity, and insufficient physical activity.
- Dietary substances that appear to increase the risk of cancer include fats, alcohol, salt-cured or smoked meats, nitrate- and nitrite- containing foods, and red and processed meats.
- Alcohol intake should be limited to no more than two drinks per day for men and one drink per day for women.
hormonal agents
- Tumor growth may be promoted by disturbances in hormonal balance, either by the body’s own (endogenous) hormone production or by administration of exogenous hormones.
- Cancers of the breast, prostate, and uterus are thought to depend on endogenous hormonal levels for growth.
- Hormonal changes related to the female reproductive cycle are also associated with cancer incidence:
- Early onset of menses (before age 12)
- Delayed onset of menopause (after age 55)
- Nulliparity
- Delayed childbirth (after age 30)
detection and prevention of cancer (primary prevention)
Concerned with reducing the risks of disease through health promotion and risk reduction strategies.
Programs may focus on the hazards of tobacco use, nutrition, and lifestyle changes.
detection and prevention of cancer (secondary prevention)
Involves screening and early detection activities that seek to identify early stage cancer in individuals who lack signs and symptoms suggestive of cancer.
Goal is to decrease cancer morbidity and mortality.
Mammograms, Digital Rectal Examinations (DRE), and PSA blood tests.
detection and prevention of cancer (third prevention)
Focuses on monitoring for and preventing recurrence of the primary cancer as well as screening for development of second malignancies in cancer survivors
Proliferative Patterns
- Hyperplasia- increase in the number of cells
- Metaplasia- conversion of one type of mature cell into another type of cell
- Dysplasia- bizarre cell growth
- Anaplasia- lack normal cell characteristics, shape, and organization
- Neoplasia- uncontrolled cell growth that follows no physiologic demand
Carcinoma
tissue of origin: epithelial
-glandular or -squamous
characteristics: Accounts for 80% - 90% of all cancers
- Organs or glands capable of secretion.
- Covers or lines all external and internal body surfaces.
term: adenocarcinoma or squamous cell carcinoma
examples:
- Adenocarcinoma of breast, lung, prostate
- Squamous cell cancer of the skin, lung, esophagus
sarcoma
tissue of origin: Connective or Supportive -Bone -Cartilage -Adipose -Smooth muscle -Skeletal muscle -Fibrous tissues -Membranes lining body cavities -Blood vessels
characteristics: Cancer of bone Rare, from within bones Deep soft tissue Very rare Most common in young Long or flat bones Related to asbestos exposure Related to occupational exposure to vinyl chloride monomer
term: Osteosarcoma Chondro-sarcoma Liposarcoma Leiomyo-sarcoma Rhabdo-sarcoma Fibrosarcoma Mesothelioma Angiosarcoma
examples: Femur, humerus Femur, pelvis Retroperitoneum, thigh Uterus, intestines, stomach Head and neck, limbs Femur, tibia, mandible Pleura or peritoneum Liver, heart
Myeloma
tissue of origin: plasma cells
characteristics: Produced by B-cell lymphocytes; plasma cells produce antibodies.
Term: N/A
Example: N/A
Lymphoma
Tissue of origin: Lymphocytes Characteristics:Two main classifications; may involve lymph nodes and/or body organs. Term: -Non-Hodgkin lymphoma -Hodgkin lymphoma Example: -B-cell lymphoma -T-cell lymphoma -N/A
Leukemia
Tissue of origin: Hematopoietic cells in the bone marrow -White blood cells -Lymphocytes -Red blood cells Characteristics: Involves various cell lines produced in the bone marrow N/A N/A Involves overproduction of RBCs and is associated with increased levels of WBCs and platelets; also risk of additional bone marrow disease Term: Myelogenous
Lymphocytic
Erythremia
Examples:
Acute myelogenous leukemia
Acute lymphocytic leukemia
Polycythemia vera