Cancer Flashcards
(176 cards)
Hypertrophy
– growth that causes tissue to increase in size by enlarging each cell.
Hyperplasia
growth that causes tissue to increase in size by increasing the number of cells.
Neoplasia
– any new or continued cell growth not needed for normal development or replacement of dead and
damaged tissues.
Cell growth
Most types of altered cell growth are benign, but nearly 1.5 million people in U.S. and Canada diagnosed with cancer each year (ACS, 2008).
longer life span
increase in exposure to carcinogens
Benign Tumors
ll
What are the steps in carcinogenesis?
Initiation – Step 1 in carcinogenesis. Exposure to carcinogen which penetrates cell, damage DNA, and change or mutate the cell. Irreversible, but only leads to cancer if cell division is not impaired.
Promotion – enhancement of growth of initiated cell. Normal hormones and body proteins, like insulin and estrogen, can cause altered cells to divide more frequently. Shortens the latency period.
Progression – increasing malignancy over time. To become a health problem, tumor must develop it’s own blood supply: TAF; less resemblance to original initiator, increasing malignancy.
Metastasis – breaks away from primary location and establishing remote colonies
True or false
80% of cancer come from external factors
True
Top four common sites of cancer
BBLL
- Brain
- Breast
- Lung
- Liver
How do you grade a tumor?
Initiation – Step 1 in carcinogenesis. Exposure to carcinogen which penetrates cell, damage DNA, and change or mutate the cell. Irreversible, but only leads to cancer if cell division is not impaired.
Promotion – enhancement of growth of initiated cell. Normal hormones and body proteins, like insulin and estrogen, can cause altered cells to divide more frequently. Shortens the latency period.
Progression – increasing malignancy over time. To become a health problem, tumor must develop it’s own blood supply: TAF; less resemblance to original initiator, increasing malignancy.
Metastasis – breaks away from primary location and establishing remote colonies
What are oncogenes?
Oncogenes are not abnormal genes – part of every cell’s make-up. Oncogenes are activated by External and
Personal factors.
External factors for cancer
External Factors – 80% of all cancers in North America
Chemical – 30% related to tobacco, single most preventable source. Tobacco is an initiator and a promoter.
Physical – Radiation, chronic irritation, and tissue trauma, scars. (frequent cell division increases risk for mutation)
Viral – when viruses infect body cells and break DNA strands, mutation may activate the oncogene or damage
suppressor cells. Oncoviruses are viruses known to cause cancer: EBV, HBV, HCV, HPV,
Cancer prevention
Avoidance of carcinogens
Skin cancer – sunscreen; avoid sun exposure
-Lung cancer – eliminate tobacco; environmental asbestos
-Modifying associated factors
-alcohol,
-Diet
-Multiple sex partners
-Removal of ‘at-risk’ tissues
-moles
-polyps
-breasts
Chemoprevention – drugs, chemicals, natural nutrients to disrupt cancer development
ASA, Celebrex – reduce risk of colon cancer
Vit D, Tamoxifen – reduce risk of breast cancer
Lycopene – prostate cancer
Vaccincation – Gardasil for HPV
Cancer Screening
Regular Screening does not reduce incidence but can reduce types of cancer death - mammography (over 40) clinical breast exam colonoscopy (50) PSA (50)
Features of early embryonic cells
Rapid and continuous cell division Anaplasia Large nuclear-to-cytoplasmic ratio Pluropotency Loose adherence Migration No contact inhibition Normal chromosomes(23 pairs) Day 8, commitment: oncogenes suppressed(off) or expressed (on) in different cell types
Features of benign tumors
Continuous or inappropriate cell growth Specific morphology Small nuclear-to-cytoplasm ratio Specific differentiated functions Tight adherence No migration Orderly growth Normal chromosomes(23 pairs)
Features of cancer cells
-Rapid or continuous cell division
-Anaplasia
-Large nuclear-to-cytoplasmic ratio
-Specific functions lost
-Loose adherence
-Migration
-No contact inhibition
-Abnormal chromosomes (aneuploidy)
lost (23), or broken
Cancer development: initiation
Initiation – Step 1 in carcinogenesis. Exposure to carcinogen which penetrates cell, damage DNA, and change or mutate the cell. Irreversible, but only leads to cancer if cell division is not impaired.
Cancer development: promotion
Promotion – enhancement of growth of initiated cell. Normal hormones and body proteins, like insulin and estrogen, can cause altered cells to divide more frequently. Shortens the latency period.
Cancer development: Progression
Progression – increasing malignancy over time. To become a health problem, tumor must develop it’s own blood supply: TAF; less resemblance to original initiator, increasing malignancy.
Cancer development: Metastasis
Metastasis – breaks away from primary location and establishing remote colonies
Common sites of metastasis
- Breast
- Lung
- Colorectal
- Prostate
- Melanoma
- Brain cancer`
Grading
Grading – compares the cancer cell with the normal cell from which it arose. Classifies cellular aspects of the cancer. Some cancer cells are more malignant than others, vary in aggressiveness and sensitivity to treatment.
Ploidy
Ploidy – description of cancer cells by chromosome number and appearance. Aneuploidyincreases with the degree of malignancy
Staging
Staging – determines the exact location and degree of malignancy at diagnosis. Influences the selection of therapy. Clinical; Surgical; Pathologic.
T – Primary tumor: Tx, To, Tis, T1, T2, T3, T4
N – Regional lymph node involvement: Nx, No, N1, N2, N3,
M – Distant metastasis: Mx, Mo, M1