chemotherapy - pharm E4 Flashcards
cell cycle
G0: rest phase
G1: cell growth
S: DNA synthesis
G2: prepare to divide
M: mitosis (division)
growth fraction
the ration of proliferating cells to resting cells (G0)
higher amount in prolif = high GF, more in G0 = low G0
what growth fraction rate is harder to kill
the low growth rate
malignant tumors initially grow very
rapidly (high growth fraction)
as the size of the tumor increases, the growth fraction rate and what does it create
lowers -> a necrotic core, decreased nutrient supply at core, more cells in G0
barriers to success
-100% kill required for cure
-toxicity
-late detection
-tumor response
-drug resistance
-cell heterogeneity
same dose treatment
to kill the cancer cells, patient needs to have the same dose of chemo every time but the problem is that in the beginning the pt might be able to tolerate the dose for a few rounds but as they grow weaker they might not be able to tolerate it
what is the earliest we can detect cancer
when it is 1cm in diameter (& the cancer already has a billion cells)
intermittent chemo
Goal: 100% cancer cell death w/ limited normal cell injury
-needs a balance to let normal cells recover and aggressive treatment
combination therapy
-multiple drugs are better than one
-Adv: reduces drug resistance & normal cell injury
-increases cancer cell killed
don’t pair drugs that have the same toxicity
optimal dosing : dosing schedule
-maximize results
-cell cycle specific agents
-keep active drug present in body as long as possible so it can hit all parts of the cell cycle
optimal dosing: regional drug therapy
-access to tumors
-high drug concentrations
-decrease systemic toxicity
ex: intra arterial, intrathecal, intraperitoneal, intravesical
acting on the tumor, not the cell
usual toxicities from chemo
-N/v for several days after chemo
-1 to 2 wks after first round: decreased WBCs, RBCs, pallor, platelets, diarrhea, alopecia, fatigue
-neutropenia, erythrocytopenia, thrombocytopenia (bone marrow)
-stomatitis & GI tract injury & malnutrition
-hyperuricemia (kidney risk)
magic mouth wash
-prescription “cocktail” for stomatitis
-swish, gargle & spit 5-10ml q6 prn
-not curative
reproductive toxicities of chemo
do not take while pregnant / get pregnant while on
-can cause sterility in men
chemo is the treatment but aslo a
carcinogen so can cause organ damage
anti cancer agents
-cytotoxic agents
-hormonal agents
-biologicals
-targeted drugs
cytotoxic agent
cell death
hormonal agents
block effects of hormones on tumor
ex) tamoxifen
biologics
alter the body’s response to cancer
ex) interferon therapy
targeted drugs
new class, targets only cancer cells
ex) bevacizumab
cytotoxic agents: MOA
disrupt DNA synthesis & mitosis
what drugs are considered cytotoxic agents
alkylating agents
antimetabolites
antitumor antibiotics
mitotic inhibitors
immune check point inhibitors
allow for immune cells to respond more strongly to cancer
T cell transfer therapy
boost natural ability of the T cells to fight cancer
taken out of body, grown in lab, put back in for this effect
Monoclonal abx
used to mark the cancer cells so that they are better seen by body’s immune system
