signs common to cancer and their mechanisms Flashcards
common signs
- lump
- virchow’s nodes
- pyrexia
- night sweating
- weight loss
- neutropenic sepsis
- nail changes
- lymphedema
what does neoplasia mean
it is a new growth
what does carcinoma mean
epithelial malignancy
what does sarcoma mean
connective tissue malignancy
how does a mutation affect the DNA
a point mutation will cause a change in the DNA bases which affects the protein that is produced which can result in cancer
what does an oncogene do
it stimulates cell proliferation
what happens when an oncogene is mutated
it can lead to an increase in the rate of cell proliferation and is uncontrolled
what does a tumour suppressor gene do
it slows down cell proliferation
what happens when a tumour suppressor is mutated
- the suppressor does not work and proliferation is no longer controlled
- if there are two mutations to the gene then there is nothing to stop the cell proliferation
what is virchows node
- the left supraclavicular lymph node was enlarged with a connection to abdominal and pelvic malignancy
- it can be the first sign of gastric cancer
how does metastasis occur
primary cancer can be spread through the lymphatic system and through the blood stream into the rest of the body for it to develop elswhere
how do you get a tumour in the lymph from other cancers
if cancer enters the lymphatic ducts where the tumour is then this can travel to the lymph nodes where it will stay a grow
what is pyrexia
- a higher than normal body temperature
- caused in response to infection by bacteria or viruses
what is a neoplastic fever
a fever that develops as a manifestation of malignancy
why does malignancies induce fevers
- release of pyrogenic cytokines from tumour cells or from macrophages are responding to the tumour
- cytokines induce prostaglandin E2 which acts on the hypothalamus, changing the set point
what are night sweats
excessive perspiration while asleep at night alongside an increase in heart rate and chills
what causes night sweats
- autoimmune disorders
- bacterial infections
- certain cancers
- drug addition
- hormonal changes associated with menopause
- medications
- overactive thyroid or thyroid disease
- sleep disorders
- stroke
- TB
why do night sweats happen
the bodies thermoregulation gets mixed messaging resulting is sweating in aims to regulate temperature
cancers causing night sweats
- they come alongside other symptoms such as weight loss and fever
- they are persistent not sporadic
- they are linked to carcinoid tumours, adrenal tumour, leukaemia and lymphoma
- can be side effects of treatments
pathway of temperature regulation (hot)
- stimulus increases body temperature
- body becomes warmer than hypothalamic set point
- activates heat loss centre in hypothalamus
- sweat gland are activated and skin blood vessels dilate
- body temperature decreases
pathway of temperature regulation (cold)
- stimulus decreases body temperature
- blood cooler than hypothalamic set point
- activates heat promoting centre in the hypothalamus
- skin blood vessels constricted and skeletal muscles are activated and shivering begins
- body temperature increases
what is cancer cachexia
a multifactorial syndrome defined by an ongoing loss of skeletal mass that can be reversed by eating
what is the mechanism of cancer cachexia
- a physiological response of substrate mobilization driven by inflammation
- the release of proinflammatory cytokines from the tumour triggers the brain to release energy which is then used for the cancer to grow further meaning more cytokines for more energy…
- energy is stored in both adipose and skeletal muscle and can be released from both
what cytokines do cancer cells produce
TNF alpha
interleukin 6
what is neutropenic sepsis
a temp of over 38C or other sign of sepsis in someone with a low neutrophil count
what are neutrophils
white blood cells (found in the blood stream) that engulf and destroy bacteria and other pathogens
why do cancer patients get neutropenic sepsis
chemotherapy kills the neutrophils meaning that patients cant fight off infections making cancer patients more likely to get sepsis
how does chemotherapy affect the nails
drugs given interfere with normal kinetics of nail matrix keratinocytes
what are beau’s lines on nails
transverse depressions on the nail surface from a decrease in nail plate production
what is onycholysis
the nail plate becoming detached from the nail bed due to toxicity of the nail bed epithelium
what are the phases of the cell cycle for chemo to target
G2/M checkpoint: Cell size, DNA replication
SAC checkpoint: chromosome attachment
G1/S checkpoint: cell size, nutrient, DNA damage, growth factors
intra-S checkpoint: DNA damage, DNA replication
what is the negative of using alkylating agents
they damage DNA which can then affect the bone marrow and them making red blood cells which can result in leukemia
how do alkylating agents work
- they damage the DNA to stop it from reproducing
- they work in all stages of the cell cycle
how do antimetabolites work
- they interfere with DNA and RNA by acting as a substitute form RNA and DNA building blocks
- then causing DNA to not be able to copy itself for reproduction
how to anti-tumor antibiotics work
they change the DNA inside the cancer cell to stop further growth
how do topoisomerase inhibitors work
interfering with topoisomerases which helps to sperate the DNA strands so they can’t be copied
how do anthracyclines work
they interefere with enzymes involved in copying DNA during the cell cycle
how do mitotic inhibitors work
- they stops cells from dividing to form new cells
- can also damage cells in all phases by keeping enzymes from making proteins for replication
what is lymphedema
lymphatic fluid retention causing tissue swelling
how does cancer treatment cause lymphedema
treatment affect the lymph nodes which affect their drainage do lymph fluid accumulated in the interstitial tissue
how does radiotherapy treat cancer
- high energy particles destroy or damage cancer cells
- these make breaks in the DNA to stop cancer cells from growing so causing them to die
