Treatment of Cancer

Question 1

4 phases of the cell cycle

Answer 1

G1 phase: RNA & protein synthesis, cell growth, DNA repair
S phase: DNA completely replicated
G2 phase: additional synthesis of RNA, protein & specialized DNA
M phase: mitosis

Question 2

Alkylating agents

Answer 2

One of the first class of drugs discovered
Directly damage DNA to keep the cell from reproducing
Work in all phases of the cell cycle
Cyclophosphamide (Cytoxan)

Question 3

Cyclophosphamide (Cytoxan) Side Effects

Answer 3

Hemorrhagic cystitis
Metabolic products of cytoxan secreted into the urine
Bladder mucosa may become damaged
Need to increase fluid intake before and after infusion and empty bladder frequently
Can lead to Leukemia long term

Question 4

Alkylating agents: Nitrogen mustards

Answer 4

Cyclophosphamide (Cytoxan)

Question 5

Alkylating agents: Platinum analogs

Answer 5

Cisplatin (Platinol)

Question 6

Cisplatin (Platinol) Side Effects

Answer 6

Nephrotoxicity:
Patients must be vigorously hydrated prior, during and after cisplatin administration
Monitor electrolytes and renal function
Neurotoxicity:
Peripheral neuropathy
Ototoxicity that can lead to deafness
(Amifostine is given IV to protect against nephro/neurotoxicity from Cisplatin)

Question 7

Antimetabolites

Answer 7

Interfere with DNA and RNA growth by substituting for the normal building blocks of RNA and DNA
Damage cells during the S phase, when the cell’s chromosomes are being copied

Question 8

Classes of antimetabolities

Answer 8

Folate antagonists: Methotrexate (MTX, Trexall)
Purine analogs: Mercaptopurine (6-MP, Purinethol)
Pyrimidine analogs: Fluorouracil (5-FU), Gemcitabine (Gemzar)

Question 9

Methotrexate (MTX; Trexall) Anticdote

Answer 9

Leucovorin is given to reverse the toxic effects

Question 10

Mitotic inhibitors

Answer 10

They work by stopping mitosis in the M phase of the cell cycle but can damage cells in all phases by keeping enzymes from making proteins needed for cell reproduction
Toxicities: myelosuppression, anaphylactic reactions, peripheral neuropathy

Question 11

Mitotic inhibitors: Vincristine (Oncovin)

Answer 11

Neuropathy
Paresthesias in the fingers and toes (mild)
Symptoms can move distal to proximal and result in significant weakness
Constipation is the most common symptom of autonomic neuropathy (Start on stool softners at the beginning of therapy)

Question 12

Anthracyclines

Answer 12

Cardiotoxicity – leading to systolic CHF
Need a baseline MUGA scan
Most commonly associated with Doxorubicin (Adriamycin)

Question 13

Topoisomerase inhibitors

Answer 13

These drugs interfere with topoisomerases, which help separate the strands of DNA so they can be copied during the S phase
Topoisomerase II inhibitors can increase the risk of a second cancer (acute myelogenous leukemia (AML))

Question 14

Misc: Bleomycin (Blenoxane) Side Effects

Answer 14

Edema of the interphalangeal joints and hardening of the skin on the palms and soles of the feet
Anaphylactic or serum sickness like reaction
Pulmonary fibrosis**
Hypotensive reaction