Exam 1 - Principles of Chemotherapy Flashcards
when was breast cancer first described?
460 BC by ancient egyptians
what did hippocrates describe cancer as?
disease of black bile
what did hippocrates name cancer? what does it mean? was surgery recommended?
karkinos - greek for crab
no surgery
when was the earliest cancer treatment documented? examples?
200 AD
opium, castor oil, licorice
when was hodgkins-lymphoma described in data?
1946 - after explosion in 1942 that exposed soldiers to mustard gas
T/F: vet med is about 20 years behind human medicine when it comes to cancer treatment
true
what are the big 3 components of cancer therapy in vet med?
surgery, chemotherapy, & radiation
spay/neuter as prevention!!
what is the difference between localized & systemic therapy for cancer?
localized involves surgery & radiation, so targeted approach
systemic includes chemotherapy & immunotherapy
after determining your histological diagnosis for a tumor, what 3 questions should you consider next?
- benign or malignant?
- is surgery necessary?
- is adjuvant therapy necessary?
what are the 2 general groups of tumors that require systemic therapy?
hematopoietic tumors & tumors with high metastatic rates
what are some examples of hematopoietic tumors?
leukemias, lymphomas, & myelomas
what are some examples of tumors with high metastatic rates that require systemic therapy?
hemangiosarcoma, osteosarcoma, melanoma, AGASACA, & high grade tumors
how do sarcomas spread first?
hematogenously - organs with large capillary beds/endocrine organs
how do carcinomas spread first?
lymphatically - regional lymph nodes 1st
how do round cell tumors spread first?
both hematogenously & lymphatically
why is staging important?
you need to determine if the cancer has spread?
what are common concerns clients have about cancer treatment?
cost, side effects, prognosis, time commitment, & disfigurement
what is adjuvant therapy?
chemotherapy administered after the primary tumor has been removed
what is neoadjuvant therapy?
chemotherapy used to reduce the bulk of the tumor before local therapy
with what type of tumor would you want use neoadjuvant therapy?
mast cell
what is nadir?
lowest point of the white blood cell count or platelet count after chemotherapy
when making a drug plan for a tumor, why is it important to know the tumor’s responsiveness?
when picking specific drugs - want to pick one that has shown prior success
why do you consider drug mechanisms when making a drug plan for chemotherapy?
you want to pick drugs that have different mechanisms from each other & the drug’s cytotoxic activity/mechanism of resistance to the drug
why is drug toxicity important when making a chemotherapy plan?
drugs may cause more side effects/problems than the cancer
what is the main goal of chemotherapy when addressing solid tumors?
often palliative in a gross setting - trying to slow things down to aim for partial remission/stable disease
what is the exception to palliative care of tumors in chemotherapy? why?
lymphoma!
curative intent - goal to reach clinical remission
in a microscopic disease setting, what are the 3 goals of chemotherapy?
- kill micro-metastatic cells throughout the body
- kill tumor cells remaining at the primary tumor site
- prevent delay or recurrence
what is the fractional cell kill hypothesis?
given drug concentration applied for a defined period of time will kill a constant fraction of the cells with regrowth of the tumor between drug cycles
what is the goal of the fractional cell kill hypothesis?
give the highest tolerated dose at the shortest frequency tolerated
the fractional cell kill hypothesis works best in what 2 cancer types? what cancer is it not great for?
great for leukemias & lymphomas
not great with solid tumors
why is the fractional cell kill hypothesis not great for solid tumors?
biochemical heterogeneity of tumors - subclinical dose to areas further from vessels can become resistance
T/F: cytotoxic chemotherapy is preferred most of the time but is more likely to induce toxicity in the patient
true
what is the goal of cytotoxic chemotherapy?
kill the cancer cell directly
how does cytotoxic chemotherapy generally work?
often aims to kill the cancer directly through DNA damage or altered cellular metabolism
when is cytostatic chemotherapy used?
palliative care or metronomic chemotherapy
how does cytostatic chemotherapy work?
often targets growth factors or other signaling pathways that may not be required for survival, but may be required for growth
when may you use the tyrosine kinase receptor inhibitor, target c-kit receptor?
mast cell tumors
when may you use the tyrosine kinase receptor inhibitor, target PDFGR?
vaccine associated sarcomas
when may you use the tyrosine kinase receptor inhibitor, target VEGFR?
AGASACA
how is the chemotherapy dose calculated?
based off of body surface area in meters squared
what is the calculation for body surface area?
(W^0.425 X H^0.725) X 0.007184
T/F: all chemotherapy is bone marrow suppressive
true
what values would you see on a CBC/chem that would make you not treat your patient with chemo?
neutrophil counts <2000 cells/dL
platelet counts <75000 cells/uL
total bilirubin >1.5 mg/dL (dose adjustment may be required)
what are the 3 pharmacologic determinants of response to chemotherapy?
absorption
metabolism
elimination
how does absorption affect the response to chemotherapy?
intestinal disease or co-administration with other drugs can impede/decrease/increase absorption
how does metabolism affect the response to chemotherapy?
liver & kidney function - if disease is present, can lead to toxicity much quicker
genetic differences - mrd1 mutation
how does elimination affect the response to chemotherapy?
liver & kidney function - if disease is present, can lead to toxicity much quicker
specific enzyme alterations
when was combination chemotherapy introduced?
1950s for childhood leukemia
why was combination chemotherapy started?
single agent drugs induced resistance rapidly
what is combination chemotherapy?
use of combo of drugs with various mechanisms of action & target resistant target subpopulations left behind in single agent protocols
what two chemo drugs are better to use on dividing cells?
doxorubicin (hydroxydaunarubicin) & vincristine (oncovin)
what is the CHOP protocol?
C - cyclophosphamide
H - hydroxydaunarubicin
O - oncovin
P - prednisone
what is important to remember if using cisplatin & methotrexate?
they are both cleared by the kidneys, so increased risk for toxicity
T/F: chemotherapy causes delayed healing of surgical wounds
true
in the chop protocol, which drugs are not cell-cycle specific?
cyclophosphamide & prednisone
what chemo drug is M phase specific?
vincristine
what chemo drug works best in the S phase of the cell cycle?
doxorubicin
T/F: chemotherapy affects rapidly dividing normal cells
what are the big 3 side effect categories of chemo therapy?
- bone marrow suppression
- alopecia
- gastrointestinal
what are 2 long term effects of chemotherapy on the bone marrow?
anemia & myelofibrosis
what cells are most effected in the blood with chemo?
neutrophils & platelets - highest turnover rate of cells
how is bone marrow suppression from chemotherapy treated?
antibiotics, drug holidays, colony growth stimulating factors, transfusions, & active surveillance
what does chemotherapy cause peripherally in the gi tract?
blunting of the crypt cells
what peripheral gi signs are seen as chemo side effects?
diarrhea, vomiting, nausea, inappetence, & weight loss
what is the most common gi sign from chemo?
peripheral - diarrhea, vomiting, & nausea
what chemo drugs cause central gi signs?
cisplatin & doxorubicin
what central gi signs are seen as chemo side effects?
vomiting
when do peripheral gi signs occur from chemo?
3-5 days after chemotherapy
what anti-emetics are used for gi side effects from chemo?
ondansetron, maropitant, & metoclopramide
also acupuncture
what antidiarrheals can be used for treating gi side effects from chemo?
metronidazole, fiber, tylosin, & imodium
what drugs can be used as appetite stimulants for treating chemo side effects?
steroids & capromorelin
what animals commonly get alopecia from chemo?
dogs with hair not fur
how is alopecia treated in chemo patients?
sweaters
what chemo drug causes fulminant pulmonary edema in cats?
cisplatin
what chemo drug commonly causes immediate vomiting in dogs?
cisplatin
if starting an animal on lomustine, what other drug should you start immediately? why?
denamarin - lomustine is hepatotoxic
what chemo drug causes sterile hemorrhagic cystitis?
cyclophosphamide
what chemo drug is known to cause DCM & arrhythmias in dogs?
doxorubicin
what can you give prophylactically in a patient you’re treating with cyclophosphamide?
pred or lasix - help prevent sterile hemorrhagic cystitis
what chemo drug is associated with a ‘walking on eggshells’ gait, pigmentation of skin, gi ulcers, hypertension, proteinuria, & muscle pain
T/F: the board won’t get you for USP 800 violations
true - but OSHA will
what is USP 800?
provides standards for safe handling of hazardous drugs to minimize the risk of exposure to healthcare personnel, patients and the environment.
who has to follow USP 800?
all facilities that store, handle, or administer hazardous drugs (not just chemotherapy)
in a facility under USP 800 regulations, what is required in the environment?
externally vented powder hood
negative air pressure around the hood
PPE
what PPE should be utilized?
gloves with a long sleeve
water resistant gowns
face mask
goggles
sharps container
chemo-waste receptacle
