growth that causes tissue to increase in size by enlarging each cell
growth of tissue by increasing the number of cells
Limited cell division
- normal cells divide for only two reasons
- -develop normal tissues
- -replace lost/damaged normal tissue
- programmed cell death
- -with each round of cell division the DNA gets shorter, when the cell runs out of DNA it then dies
each normal cell has a distinct, and recognizable appearance size and shape
every normal cell has a specific job/function it performs for whole body function
- normal cells make proteins that bind the cells together
- -exception of rbc, wbc which do not make this protein
orderly and well regulated growth
- the cells do not divide, unless body conditions are optimal.
- need for more cells, adequate space, sufficient nutrients, and other resources
reproductive resting state (G0)
cells carry out their functions but do not divide
- family of proteins that promote cells to enter mitosis and complete the cell divison process.
- -products of oncogenes
Phases of the cell cycle
-G0, G1, S, G2, M,
- G0-reproductive resting state-not dividing
- G1-cell prepares for division-takes in extra nutrients, makes more energy and produces an extra cell membrane
- S-doubles DNA through DNA synthesis
- G2-makes proteins used in actual cell division.
- M-actual mitosis-cell splint into two
is the stopping of further rounds of cell division when the dividing cell is completely surrounded and touched by other cells
normal chromosomes:23 pairs
amount of time it takes a cell to divide
- rapid and continuous cell divison, generation time =2-8 hours
- they do not respond to apoptosis(except for fingers/toes)
- early embryonic cells do not look like the mature cells they will eventually become. they are small and rounded. the nucleus takes up most of cytoplasma.
- pluripotency:unlimited potential for maturation. not bound tightly together,
without specific shape or differentiation.
at about day 8 embryonic cells start to change into differentiated cells.
early embryonic genes that control or regulate early rapid growth, they are turned off during the commitment event.
proteins are turned off/proteins are turned on.
benign tumor cells
- normal cells growing in the wrong place or at the wrong time. moles/uterine fibroids/skintags/nasal polyps.have specific shape and size of parent tissue/cell
- have tight adherence.orderly growth/ have normal chromosomes and spefic fxn
- abnormal, serve no useful fxn, and are harmful to normal body tissues.
- have rapid and continuous cell division, and shortgeneration time. do not respond to signals of apoptosis and have an unlimited life span.anaplasic, large nuclei, loose adherence, migrate, metastasize(spread) abnormal chromosomes (aneuploidy)
Steps of carcinogenesis/oncogenesis
- Initiation:first step, anything that causes normal cells to become cancer cells, if their oncogenes are turned on excessively at any time after embryonic life.(an irreversible event that can lead to cancer)A cancer cell is not a health threat unless it can divide.
- Promotion:substances that promote or enhance growth of the initiated cancer cell.(hormones like insulin, estrogen)
- Progression:is the continues change in the cancer making it more malignant over time.
- tumor must have have blood supply (TAF) makes new capillaries to tumor
time betweeen a cells initiation and the development of an overt tumor is called the latency period which could last from months to years.
original tumor that is identified by the parent tissue
secondary (metastatic) tumor
- cancer cells that move from prinary tumor to another tissue location
- bloodbourne metastasis: tumor cells released into the blood in order to colonize in a different location
General disease related consequences of cancer
- reduced immunity and blood producing fxns
- -occurs with leukemia/bone cancers;cuz bone marrow is affected
- -client is at risk for anemia and excessive bleeding
- Altered GI structure and fxn:reduction of ability to absorb and take in nutrients.
- -diet needed high in protein/carbs
- Motor and sensory deficits:when cancers invade bone/brain/compress nerves
- Decreased respiratory fxn: hypoxia and tissue perfusion are common with CA
extreme body wasting, and malnutrtion
- Prophylactic surgery:removal of at risk tissue
- Diagnostic surgery:(biopsy)
- Curative surgery:removal of all or part of suspected lesion
- Cancer control(cytoreductive) surgery:removing part of the tumor in order to reduce number of cells
- Pallitive surgery: focus is on quality of life not a cure
- Secondary surgery:rediagnosis after tx
- Reconstructive or rehab surgery:increases fxn and enhances appearance.
Radation therapy (Local treatment)
- Destroys cancer cells with minimal exposure of the normal cells.
- Gamma rays are most commonly used.
- inverse square law:radation decreases farther away from the source.
- Teletherapy:radiation source is outside of the body
- Brachytherapy:means short or close therapy(within) the patient.and is a hazard to others---hazardous in the waste products until the isotopes are eliminated usually within 48 hours. side effects:skin changes, hair loss, altered taste, fatigue, inflammation and scarring avoid sun exposure
- treatment with chemical agents, used to cure and increase survival time. the drugs are systemic and exert their damage on both cancer and normal cells as well. major complication:extravasation-movement of the needle during chemo treatment, and the drug leaks out into the surrounding tissue and the possibilty of tissue damage.
- side effects:anemia, neutropenia, Alopecia, mucositis, changes in cognition, peripheral neuropathy,