Oncology II pt 2 Flashcards
What phase of the DNA replication cycle to topoisomerase I inhibitors work?
S phase
Prevents coiling and uncoiling of double-stranded DNA helix
Irinotecan class, brand, unique concerns, boxed warnings
Topoisomerase I inhibitor
Acute cholinergic symptoms (treat with atropine)
Delayed diarrhea (treat with loperamide, up to 24 mg/day)
Pharmacogenomic conerns: patients homozygous for the UGT1A1*28 allele are at increased risk for neutropenia and delayed diarrhea
Boxed warnings for diarrhea lmao ok
What phase of the DNA replication cycle to topoisomerase II inhibitors work?
G2 phase
Blocks coiling and uncoiling of double stranded DNA phase
Etoposide class, unique concerns
Topoisomerase II inhibitor
Comes IV or capsules
IV: Toposar requires concentration of less than 0.4 mg/mL
Etopophos doesn’t have concentration limits, use in pts on fluid restriction
Etoposide capsules (Vepesid) are refrigerated. IV:PO ratio is 1:2
Boxed warning for myelosuppression, can have hypersensitivity reactions
During what phase do pyrimidine analog antimetabolites work?
S phase Active metabolute (F-UMP) incorporated into RNA to replace uracil and inhibits cell growth
Fluorouracil class, brand, unique concerns
Pyrimidine analog antimetabolite
Adrucil, Efudex
Give leucovorin to increase efficacy Dihydropyrimidine dehydrogenade (DPD) deficiency increases risk of severe toxicity
Capecitabine class, brand, unique concerns
Pyrimidine analog antimetabolite
Xeloda
Oral prodrug of fluorouracil
DPD deficiency increases risk of severe toxicity
Folate antimetabolites act during what phase of the cell cycle?
S phase
DNA synthesis
Leucovorin place in therapy
Methotrexate, “rescue” must be given with high doses of MTX (> 500 mg/m2)
Also given with 5-FU to increase efficacy
Note: LEVOleucovorin is also available, dosed at 1/2 the dose of leucovorin
Methotrexate brand, unique concerns
Trexall, Oltrexup, Rasuvo, Xatmep
May require leucovorin rescue if dose exceeds >500 mg/m2
Doses for cancer much higher than RA or psoriasis
Hydration and IV sodium bicarbonate must be given to alkalinize the urine and decrease risk of nephrotoxicity
Drug interactions w MTX
NSAIDs, salicylates
Decreases clearance of methotrexate
Tretinoin unique concerns
Absolutely contraindicated in pregnancy
Boxed warning for RA-APL differentiation syndrome “potentially fatal complication of induction chemotherapy in patients with acute promyelocytic leukemia (APL)”
Arsenic trioxide unique concerns
QT prolongation
Boxed warning: RA-APL differentiation syndrome, QT prolongation
Asparaginase, pegasparagase unique concerns, side effects
Hypersensitivity reactions, pancreatitis, prolonged prothrombin time (PT/INR)
Bleomycin unique concerns
Not myelosuppressive
Maximum lifetime dose of 400 units due to pulmonary toxicity risk
Boxed warning for pulmonary fibrosis
Side effects: hypersensitivity reaction
Everolimus concerns, side effects
CYP3A4 major substrate
Side effects dyslipidemia, rash, stomatitis, interstitial lung disease
Note: Brand for cancers Afinitor, Afinitor Disperz. Zortress is indicated for transplantation