Exam 1 - Introduction To Oncology Flashcards
what is cancer?
5 or 6 mutations minimum to provide a cell & progeny the hallmarks of cancer
what are the 5 steps in the progression of cancer?
- precancerous dysplasia carcinoma in situ
- localized (on spot on liver)
- early locally advanced (involves more than 1 liver loves)
- late locally advanced
- metastasized
what are the 10 hallmarks of cancer?
- evading growth suppressors
- avoiding immune destruction
- enabling replicative immortality important
- tumor-promoting inflammation
- activating invasion & metastasis
- inducing angiogenesis
- genome instability & mutation
- resisting cell death
- deregulating cellular energetics
- sustaining proliferative signaling
what is an example of an intrinsic risk factor?
random errors in DNA replication
intrinsic risk factors are ________ (unmodifiable/partially modifiable/modifiable)
unmodifiable
what are the two examples of non-intrinsic risk factors?
endogenous risk factors & exogenous risk factors
between endogenous & exogenous risk factors, which is modifiable & partially modifiable?
endogenous = partially modifiable
exogenous = modifiable
what are some examples of exogenous risk factors?
radiation, chemical carcinogens, tumor causing viruses, bad lifestyles (smoking, lack of exercise, nutrient imbalances)
what are some examples of endogenous risk factors?
biologic aging, genetic susceptibility, DNA repair machinery, hormones, growth factors, & inflammation
what are intrinsic mutagens?
intrinsic risk factors - bad luck factors that interact in unpredictable ways with environmental (extrinsic) triggers to promote cancer
when is the animal getting intrinsic mutagens?
mutations are occurring during normal cell DNA replication
what is the process in which cell mutations are occurring?
every time a cell divides, each daughter cell is likely to carry at least a few hundred mutations, but most are silent
what happens if the mutations daughter cells are carrying are not silent?
ability to disable anti-cancer machinery such as tumor suppressor genes & proto-oncogenes
what is malignant transformation of cells?
genetic & epigenetic alterations & bypass of tumor suppressor mechanisms
what are some examples of tumor suppressor mechanisms?
contact inhibition, senescence (exhausted telomeres, excess DNA damage, oncogene activation), & immune surveilance
what are the 3 steps of carcinogenesis?
- initiation
- promotion
- progression
what is the initiation step of carcinogenesis?
alteration, change, or mutation of a gene - arises spontaneously or is induced by exposure to a carcinogen
what is the promotion step of carcinogenesis?
lengthy & reversible process in which actively proliferating pre-neoplastic cells accumulate during this phase
what is the progression step of carcinogenesis?
phase between pre-neoplastic & invasive neoplastic lesions
why do elephants not die of cancer?
they have an increased number of P53 genes
what is the P53 gene?
tumor suppressor gene - if a cell with faulty DNA is replicating, this gene can arrest the process & allow it to move forward only once the DNA is fixed or can kill the cell to get rid of the bad DNA
what is the LIF gene?
zombie gene - LIF6 is in charge of carrying out orders from P53 to eliminate damaged cells
elephants also have more of these
how many p53 genes do humans & dogs have compared to elephants?
humans & dogs - 2
elephants - 40
what is benign cancer?
proliferation of well differentiated cells that cause compression rather than invasion of tissue
does benign cancer metastasize?
no
what is malignant cancer?
cells are not well differentiated & there is invasion of the surrounding tissue
does malignant cancer metastasize?
yes
what is metastatic cancer?
spread of a malignant tumor to other areas/tissues within the body such as lymph nodes, lungs, liver, spleen, & bone
what are the general 6 steps of tumorigenesis?
- initiation
- hyperplasia
- dysplasia
- in situ cancer
- invasive cancer
- metastasis
what is the initiation step of tumorigenesis?
oncogene activation in the altered cell
what is the hyperplasia step of tumorigenesis?
cell begins dividing more rapidly than normal
what is the dysplasia step of tumorigenesis?
altered cells with increased growth potential
what is the in situ step of tumorigenesis?
cells rapidly grow & stay in one place
what is the invasive cancer step in tumorigenesis?
cells invade normal tissue & enter blood & lymph
what is the metastasis step in tumorigenesis?
metastases form at distant sites
what are 6 characteristics of cancer-promoting in cell invasion & metastasis?
- promoting cancer metastasis
- inducing dormant cancer cell survival
- supplying alternative source of energy
- inhibit cancer cell death
- reducing the sensitivity of cancer cells to the stimulus
- increasing drug resistance
what are the 5 components of metastasis?
- invasion
- intravasation
- dissemination
- extravasation
- colonization
what is the only way tumors can be graded?
histopathologically
why is tumor grading important?
has been linked to biologic behavior in some tumor types - predictive of how it may act
what is tumor staging?
determining where in the body the cancer is located by using imaging 9CXR, AUS, CT, MRI) & molecular & functional tests (Pet CT)
what is the number one rule of oncology?
know WHAT you are treating before prescribing treatment
why is it import to know what you’re treating prior to prescribing treatment?
first surgery is the best chance for a cure - many patients require multimodal therapy
not all cancer is the same!!!
why is it important to understand the biology of the tumor before prescribing treatment?
tumors spread differently - how it metastasizes & where
what are examples of ways to obtain a diagnosis of cancer prior to prescribing treatment?
FNA, cytology, biopsy, & histopathology
what should be considered as far as limitations in the rules of oncology?
do you have the treatment modalities needed? knowledge/experience? surgical skills? appropriate support/equipment? what is best for your patient?
__% of households have at least 1 pet
62%
how many pets were recorded as owned in the USA in 2012? how many dogs? cats?
164 million
dogs - 83.3 million
cats - 95.6 million
T/F: cancer is a major cause of mortality & morbidity in companion animals
true
how many dogs & cats develop cancer each year?
4 million
__% of dogs that live >10 years die of what? __% of deaths regardless of age are also due to?
45% - cancer
25% - cancer
what is the most significant health concern among dog owners?
cancer - 41%
why are companion animals a good comparative models for cancer?
share the same environment as humans, clinical trials are more economical, they are large enough for higher resolution imaging & multiple sampling, similar physiology & metabolism for most organ systems/drugs, & have a higher incidence of some cancers (osteosarcoma)
T/F: clinical & comparative oncology programs advance both animal & human cancer treatment
True
what are two main points of why cancer treatment/oncological studies in animals benefits both the patient & scientific community?
- gives patients the opportunity to receive new therapies not routinely available & cost prohibitive
- provides invaluable information for the management & treatment of cancer in humans
