N323 - Week 5 (Oncology Pharmacology - Cancer Pharmacology)

growth fraction

measure of how many cells are undergoing mitosis

-ratio of replicating cells to resting cells

chemotherapy

most effective against rapidly dividing cells

High growth fraction

many replicating cells

-EX: leukemia & lymphomas have high growth fraction -> chemotherapy more effective

-EX: hair follicles, bone marrow, GI tissue have high growth factor (explains many adverse effects; e.g. hair loss)

Low growth fraction

solid tumors, less sensitive to chemotherapy

Cell cycle

G0 phase: Resting stage

G1 Phase: Synthesizes material needed to duplicate DNA

S phase: Duplicates DNA

G2 phase: Premitotic phase

M phase: Mitosis occurs

-Cell returns to G0 phase

G0 phase

cell can stay there for days, weeks, mnths or forever!

-depends on cell type

-rapidly dividing cells exit G0 quickly

Treatment for Cancer (4)

surgery (for something solid to be removed)

-radiation (targets specific area, using light waves)

-cytotoxic drugs (chemotherapy agents, target rapidly dividing cells)

-hormonal agents

Multiple drug strategy (3)

use multiple drugs from different classes -> affects different stages in cell cycle

-use different mechanisms of axn to increase cell kill

-allows for lower doses -> reduces toxicity, slower development of resistance

Chemotherapy

can cause hyperuricemia as a result of DNA degradation secondary to massive cell death

Hyperuricemia

excessive levels of uric acid in the blood

-insoluble uric crystals can get stuck in our renal tubules, nephrons and kidneys

Renal injury from hyperuricemia can be minimized by.. (2)

giving IV fluids

Prophylactic allopurinol (blocks uric acid formation)

*2 Types of Drugs Used to Treat Cancer

Cytotoxic agents

-hormonal agents

Cytotoxic Agents (6)

Alkylating Agents (Nitrogen Mustards & Platinum Compounds)

-Antimetabolites (methotrexate & 5 Fluorouracil)

-Anti-tumor Antibiotics (doxurubicin, danunorubicin)

-Antimicrotubule Agents/Mitotic Inhibitors (vincristine, vinblastine)

Type of Alkylating Agents

Nitrogen Mustards

Platinum Compounds

**can affect any phase of cell cycle

cyclophosphamide (Cytoxan) PO

MOA:

Classification:

Cancers Tx:

Adverse Effect: (4)

Nursing Considerations: (3)

-MOA: form bonds w/ DNA, prevent cell division; disrupts DNA replication

-Classification: Alkylating agent-nitrogen mustards

-Cancers Tx: ALL, CLL, AML, CML, Hodgkin lymphoma, multiple myeloma

-Adverse effect: bone marrow suppression, alopecia, thrombocytopenia, hemorrhagic cystitis

Nursing Consideration:

-Individuals of reproductive potential should use contraception for 12 mnths after drug administration

-Close monitoring of CBC w/ differential, renal, LFTs

-Educate pt importance of adequate hydration

hemorrhagic cytitis

inflammation of the bladder that involves bleeding

-can prevent this w/ adequate hydration

cisplatin (Platinol) IV

MOA:

Classification:

Primary use:

Adverse Effects: (4)

Nursing Considerations: (4)

-MOA: Bind to nucleotides - Unable to go through normal replication & move into cell arrest.. GI phase inhibitors

-Classification: Alkylating agent - platinum analog

-Primary use: testicular, ovarian & bladder cancers. Also lung, head and neck cancers

-Adverse effects: ototoxicity, nephrotoxicity!!; neuropathy, bone marrow suppression

Nursing considerations:

-Close monitoring of renal fxn

-ensure vigorous hydration prior to infusion

-assess hearing frequently (ototoxicity)

-assess lab values, CBC, Chem panel, LFTs

Antimetabolites

methotrexate (MTX) (Otrexup, Trexall)

5 Flurouracil (5-FU) (Adrucil) IV

** target a metabolite needed to divide -> target S phase

Methotrexate (MTX) (Otrexup, Trexall)

MOA:

Classification:

Cancers Tx:

Adverse Effect: (4)

Nursing Considerations: (4)

MOA: blocks synthesis of folic acid (vit B9) to inhibit replication. Powerful immunosuppressant - S phase specific

-Classification: antimetabolites-antifolate (DMARD)

-Primary use: many cancers, MTX for rheumatoid arthritis

-Adverse Effects: bone marrow suppression; rare alopecia, thrombosis, thrombocytopenia!! (watch for bleeding)

Nursing considerations:

-Not for use in pregnancy (known teratogen); avoid pregnancy for 6 mnths after

-Monitor CBC, renal labs, LFTs

-limit ETOH intake during use of medication

-Monitor for bleeding

** given PO, IV, IM but also intrathecally (straight into CSF)

5 Fluorouracil (5-FU) (Adrucil) IV

MOA:

Classification:

Primary use:

Adverse Effect: (3)

Nursing Considerations: (2)

MOA: inhibits thymidylate synthetase, thereby depriving cells of thymidylate needed to make DNA (S-phase specific)

-Classification: antimetabolites-Pyrimide Analog

-Primary use: mainly solid tumors, adjuvant treatment for many other cancers

-Adverse Effect: immune system suppression; lack of appetite, hair loss

Nursing Considerations:

-Not for use in pregnancy

-Monitor CBC, electrolytes, renal labs

doxorubicin (Doxil, Adriamycin), daunorubicin (Cerubidine)

MOA:

Classification:

Primary use:

Adverse Effect: (2)

Nursing Considerations: (3)

-MOA: inhibit cell growth through cytotoxicity, trigger apoptosis (slips btwn base pairs of DNA (intercalation) & distorts DNA)

-Classification: Anthracylcines

-Primary use: Hodgkins, Non-Hodgkins Lymphoma, Sarcomas, Lung, stomach, breast, ovary, testes, thyroid

-Adverse effects: bone marrow suppression, cardiotoxicity!!

Nursing considerations:

-Extreme caution w/ heart failure or cardiomyopathy pts, Monitor cardiac fxn

-Monitor CBC, electrolytes, LFTs, uric acid

-Causes red discoloration of urine, sweat, & tears

vincristine (Oncovin), vinblastine (Velban)

MOA:

Classification:

Primary use:

Adverse Effect: (4)

Nursing Considerations: (4)

-MOA: disrupts M-phase of the cell cycle (mitosis) leading to cell arrest & apoptosis

-Classification: Vinca alkaloid

-Primary use: Hogkins, Non-Hodgkins Lymphoma, Kaposi's Sarcoma, breast & bladder cancers (Testes: vinblastine)

-Adverse Effects: neurotoxicity & periph neuropathy!!, bone marrow suppression w/ Vinblastine, alopecia

Nursing Considerations:

-Monitor for muscular weakness

-Does not cause bone marrow depression

-Monitor for peripheral neuropathy

-Need central line for infusion

Vesicant drugs

drugs given only by the IV route into a large vein (use central line)

-can cause severe local injury w/ extravasation

-EX: vincristine

Hormonal Agents

hormonal-antiestrogens (tamoxifen)

-androgen deprivation (leuprolide)

tamoxifen (Soltamox)

MOA:

Classification:

Primary use:

Adverse Effect: (6)

Nursing Considerations: (4)

Commonly used: tamoxifen (Soltamox)

MOA: competes w/ estrogen at binding receptors, stops growth of estrogen dependent tumors; used as prevention in high risk cases

Classification: Estrogen receptor (blocker) antagonist

Primary use: breast Cancer (pre & post menopausal)

Adverse Effect: thrombocytopenia, hot flashes, hypercalcemia, GI upset; risk of uterine cancer & pulmonary embolism

Nursing Considerations:

-Individuals of reproductive potential should use contraception for 2 mnths after drug administration

-Monitor for DVT (leg swelling, tenderness) or PE (shortness of breath)

-Avoidance of grapefruit jucie

-Administer w/ food or fluids to decrease GI irritation

DVT & PE

DVT: deep vein thrombosis -> clot in leg -> leg swelling

-PE: pulmonary embolism -> clot travels through body & ends up in pulmonary vasculature of lungs -> shortness of breath

leuprolide (Lupron) IM, SubQ

MOA:

Classification:

Primary use:

Adverse Effect: (4)

Nursing Considerations: (2)

-MOA: blocks effects of adrenal androgens on prostate cells by decreasing testosterone

-Classification: Gonadotropin releasing hormone agonist

-Primary use: Prostate cancer

-Adverse Effect: decreased libido, gynecomastia (growth of breast in males), hot flashes, lowered blood sugar

Nursing Considerations:

-not for use in pregnancy

-monitor glucose levels closely & symptoms of hypoglycemia

How to handle antineoplastic drugs: (drugs for cancer) (4)

double flushing of bodily fluids in the commode

-use special hampers for disposal of all objects that contact the pt's body fluids

-use personal protective equipment

-special concerns if chemotherapy liquid spills

Nursing Implications of Alkylating drugs (5)

monitored for expected effects of bone marrow suppression

-expect nausea, vomiting, diarrhea, stomatitis

-hydration is important to prevent nephrotoxicity

-Report any ringing/roaring in the ears - possible ototoxicity

-Peripheral neuropathies may occur - report tingling, numbness, pain in extremities

Nursing Implications of Cytotoxic (antitumor) antibiotics (4)

expect the bone marrow suppression, nausea, vomiting, diarrhea, stomatitis

-monitor pulmonary status

-monitor for nephrotoxicity, liver toxicity

-monitor cardiovascular status

Signs of Oncologic Emergencies (7)

infections

-allergic rxns

-bleeding

-metabolic aberrations (liver dysfxn)

-stomatitis w/ severe ulcerations

-bowel irritability w/ diarrhea

-pulmonary, renal, liver, cardiac toxicity