Chemotherapy II: Alkylating Agents Flashcards
What do the alkylating agents alkylate?
N-7 of guanine
Resistance in alkylating agents is due to:
Enhanced DNA repair
Binding to sulfar containing molecules
Bis(chloroethyl)aminea (2)
Cyclophosphamide
Ifosfamide
Cyclophosphamide MOA
Bifunctional alkylater: intrastrand cross link or interstrand cross link; DNA replication impaired
Cyclosphosphamide activation
In the liver (P-450 oxidase)
Cyclosphosphamide SE
Nausea, vomiting, hair loss, myelosupression
HEMATURIA (phosphoramide mustard is irritating)
How can you decrease hematuria associated with Cyclosphosphamide?
Give drug in morning, frequent urination, maintain hydration
Cyclosphosphamide Indication
breast cancer
NON-HODGKIN’s LYMPHOMA (diffuse large B cell)
Ifosfamide
Bischloroethylamine
1/5 alkylating ability of Cyclosphosphamide
MUCH HIGHER DOSE required
Ifosfamide SE
Blood in Urine
Must give Mesna (uroprotectant)
Lethargy, confusion
MYELOSUPPRESSION= d-l
Mesna
Monomer binds metabolites in urine, eliminates hematuria of Ifosfamide
Ifosfamide Indication
Sarcoma
Testicular cancers
Temozolomide
Monofunctional alkylating agent
Temozolomide MOA
Methylates DNA
Temozolomide SE
Myelosuppression, nausea, vomiting, hair loss
What must you give to a patient that is on Temozolomide for a prolonged period?
Prophylaxis for PCP (PJP) pneumonia
Temozolomide Indication
Primary brain tumors
glioblastoma
Platinum (Pt) Coordination Compounds MOA
Undergo sequential aquation reactions
aquated species = DNA reactive species
Covalently bind DNA at N7 of adenine and guanine
Platinum (Pt) Coordination Compounds
Cisplatin
Carboplatin
Oxaliplatin
Cisplatin SE
NEPHROTOXIC = d-l
*give with saline hydration and mannitol diuresis
emetogenic, neuropathy, hypomagnesemia, high frequency hearing loss
What should you check in a patient taking Cisplatin?
Mg levels
What should you co-administer with Cisplatin?
Saline hydration and mannitol diuresis
Cisplatin Indication
Curative in TESTICULAR CANCER
lung, ovary, head, neck, bladder cancer
What type of patient should not receive cisplatin?
CHF, renal insufficiency
Must be able to tolerate fluid load
Why is Cisplatin difficult to administer
Patient has to be in clinic for a very long time
Is Carboplatin nephrotoxic?
NO!
Carboplatin dose-limiting SE
MYELOSYPPRESSION
If a patient is resistant to cisplatin, can you give carboplatin instead?
NO! Cross resistant
Can you give carboplatin to a patient on dialysis?
YES! Easier to give!
Carboplatin indications
Same activity as cisplatin
Oxiplatin indication
COLORECTAL CANCER
Oxiplatin dose-limiting SE
MYELOSUPPRESSION
Oxiplatin SE (others)
Vein irritant (portacath)
Acute cold induced neuropathy
Chronic sensory neuropathy
Plant Alkaloids
Vincristine, Vinblastine, Taxol, Etoposide
Which of the plant alkaloids are cell cycle specific?
Vincristine, Vinblastine, Taxol
Which of the plant alkaloids inhibit mitotic spindle formation
Vincristine, Vinblastine
Which of the plant alkaloids inhibits the breakdown of the mitotic spindle?
Taxol
Which of the plant alkaloids inhibits topoisomerase II?
Etoposide
Vincristine MOA
Prevents polymerization of tubulin
Cell cyle specific (M-phase)
In which patients should you lower the dose of Vincristine?
Pts with elevated bilirubin (excreted in the bile)
Vincristine dose-limiting SE
NEUROPATHY
loss of ankle jerk reflexes, N/T in fingers
Does vincristine cause myelosuppresion?
NO!
Vincristine indications
Lymphoma, Hodgkin’s disease, Lymphoblastic leukemia
What are the differences between vincristine and vinblastine?
Vinblastin is less neurotoxic but causes more myelosuppression
Paclitaxel = Taxol MOA
Cell cycle specific (M-phase)
Prevents tubulin disassembly
In which patients should you dose reduce Taxol
Hepatic dysfunction
Taxol SE
Myelosuppression, hair loss, nausea, vomiting, stomatitis, peripheral sensory neuropathy, myalgias, arthralgias
*Premedicate to prevent allergic reactions
Carbotaxol = Carboplatin + taxol
Use to treat lung cancer, ovarian cancer, GE junction cancer
Taxol Indication
OVARIAN, LUNG, GASTROESOPHAGEAL, BREAST cancers
Docetaxel indication
prostate cancer
Albumin bound paclitaxel benifits
No allergic reactions
Less myelosuppression
Less neuropathy
Carbaxitaxel indication
Prostate cancer
Etoposide MOA
Cell cycle specific (G1-S phase)
Inhibits topoisomerase II
Double strand DNA breaks
Etoposide SE
Nausea, vomiting, hair loss
MYELOSUPPRESSION = d-l
What is the total dose you can give of Etoposide
2 gm/M^2
LEUKEMOGENIC
Who should you dose reduce etoposide in?
Renal/hepatic dysfunction
Etoposide Indication
TESTICULAR, lung cancer (small cell), lymphomas