Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
WEEK 22:
Introduction to causes, treatment and prevention of cancer:
| Question | Answer |
|---|---|
| neoplasia | new growth |
| cause of neoplasms | genetic mutations |
| causes of cancer (3) | carcinogens, infectious agents, and inherited predisposition |
| how is cancer described as sporadic or familial | cancer is caused by acquired mutations happening during lifetime or there is a predisposition occurring often earlier in life |
| driver mutations | mutations that affect function of genes that regulate proliferation, apoptosis, immortality etc |
| passenger mutation | mutations that do not affect promotion of cancer |
| how do carcinogens lead to a high rate of mutations | radiation makes free radicals which cause DNA damage (adducts, cross-links, and strand breaks) increasing rate of mutation, DNA breaks or base changes. This may lead to errors such as incorrect bases incorporated or misjoining of chromosome ends |
| mechanisms where infectious agents can lead to cancer (5) | inflammation, oncogenes, immune suppression, individually small effects (eg chemical exposure or obesity), and intrinsic causes (eg hormones and tissue growth) |
| UK cancer screening programmes (4) | never population wide (limited to at risk groups) including breast, cervical, colon and prostate |
| who gets a breast cancer screening | 43-73 yrs (women) |
| who gets a colon cancer screening | 60-74 yrs |
| who gets prostate cancer screening | 50 yrs + (men) |
| who gets cervical cancer screening | 25-65 yrs (women) |
| BRAC1 | involved in breast and also ovarian cancers where women who have family or ethnic group with predisposition is offered testing with a follow up of masectomy if they have a mutated BRCA1 gene |
| what should be done if mutated BRAC1 gene is found | offer masectomy |
| why do pap smears work well | since normal cells of cervix are relatively uniform |
| bowel cancer and screening for it | starts as a slow growing precancerous mass |
| virtual colonoscopy | CAT scan and colonoscopy which gives 3D picture of colon and rectum (almost as sensitive as colonoscopy and 1/3 cost but not used in the UK due to unknown associated risks) |
| cancer therapeutics (4) | surgery, radiotherapy, chemotherapy, and targeted therapies |
| radiotherapy | uses beams (xrays or protons of other energy types) of intense energy to kill (damage) cancer cells to the extent they cannot survive where cancer cells are more sensitive to DNA damage |
| fractionated radiotherapy | multiple lower doses are less toxic to normal cells |
| brachytherapy radiotherapy | use of sealed sources where seeds emit radiation that dissipates over a few months |
| three dimensional conformal radiation | radiation beams scan from multiple directions to make a 3D model of the tumour to determine its size and shape especially compared to other organs |
| mitotic catastrophe | where most dividing cancer cells survive initially and progress through cell cycle despite breaks in DNA but becomes more damaged until it is so broken the cells die (mitotic catastrophe) |
| most chemotherapeutics are | natural products of bacteria or plants |
| Antimetabolites | generally interfere with DNA replication eg methotrexate |
| Alkylating agents | cause DNA cross linking eg cyclophosphamide |
| Platinum compounds | inhibit DNA synthesis eg cisplatin |
| Anthracycline antibiotics | DNA intercalation eg doxorubicin |
| Topoisomerase inhibitors | prevents ligation step eg etoposide |
| Microtubule inhibitors | variously stabilise or destabilise spindle eg paclitaxel |
| mitomycin as a chemotherapeutic | cross links DNA eg streptomyces |
| Bleomycin as a chemotherapeutic | breaks DNA strands eg streptomyces |
| Etoposide as a chemotherapeutic | topoisomerase inhibitor eg mayapple |
| vincristine as a chemotherapeutic | builds tubulin subunits and blocks division eg vincristine |
| targeted therapies | therapies based on known features of cancer cells - usually antibodies to specific antigens |
| monoclonal antibodies as a targeted therapy for breast cancer | trastuzumab targets EGFR (HER2) mutants in breast cancer by blocking effects of HER2 and encouraging the immune system to attack and kill cancer cells |
| other targeted therapies using antibodies to treat cancer (3) | small molecule inhibitors (lung, leukaemia, and colon), angiogenesis inhibitors (colon), and immune system boosters (vaccines) |
| prevention of cancer includes (3) | lifestyle changing (smoking, UV, and diet of processed meat), immunization (HPV and hepatitis vaccines), and prenatal genetic diagnosis |
| preimplantation genetic diagnosis | check sample of embryo to see if it has faulty gene and correct it eg BRCA1/2 for breast and ovarian cancer |
| most common cancers in the UK (4) | breast, prostate, lung or bowel |
| ethnicity and UK cancer incidence in males | more common in white and black males than asian males |
| ethnicity and UK cancer incidence in females | more common in white females than black and asian females |
| inherited cancer predisposition principle | inherited mutation in gene that causes a defect in machinery that guards against genome damage (either monitoring or DNA repair) eg BRCA1 |
| BRCA1 and BRCA2 genes as a strong familial predictor of breast cancer | responsible for 2-10% breast cancer cases as they normally help in DNA repair where 1:150-800 western women inherit these mutations but Ashkenazi Jewish descent have a higher risk (1:40) |
| screening and tests for bowel cancer | faecal occult blood test (FOBT), colonoscopy and virtual colonoscopy |
| why is colonoscopy better than FOBT for screening for bowel cancer | colonoscopy detects 4-5x more polyps and cancers than FOBT but more expensive |
| when is surgery used to treat cancer | when cancer is localised so surgery can remove entire tumour |
| neo-adjuvant therapy | used to shrink tumour size before surgery based on the type of cancer, stage, grade, biology and patient health |
| how do free radicals cause apoptosis of cells | damage membrane proteins which can then trigger apoptosis |
Created by:
kablooey
Popular Medical sets