Chemo Drugs Flashcards
(29 cards)
What is cancer?
Uncontrolled proliferation of cells; neoplastic cells have abnormal, unregulated growth.
What are the 5 key characteristics of cancer cells?
- Persistent proliferation 2. Invasive 3. Metastatic 4. Immortal 5. Angiogenesis
What are the three primary treatment modalities for cancer?
- Surgery 2. Radiation 3. Chemotherapy
Why is understanding the cell cycle important in cancer therapy?
Chemotherapeutic drugs often target specific stages of cell proliferation.
Why is toxicity to normal cells a major issue in chemotherapy?
Cancer cells are similar to normal cells; drugs also affect normal cells with high growth fractions.
What is the significance of the growth fraction?
High growth fraction = more susceptible to chemotherapy; includes bone marrow, GI tract, hair follicles, testes.
What does ‘100% cell kill’ mean in cancer therapy?
All cancer cells must be eradicated to cure cancer; even a few remaining cells can cause recurrence.
How does first-order kinetics affect chemotherapy effectiveness?
A constant percentage of cancer cells are killed at each dose.
Why is early cancer detection challenging?
Tumors often aren’t detected until they reach ~10⁹ cells.
List Canada’s key cancer screening recommendations.
Breast: CBE every 2–3 yrs after 50; Cervical: Pap 1–3 yrs; Colorectal: FOBT every 2 yrs after 50; Prostate: DRE/PSA; Skin: Self-checks; Testicular: Self-exams from 15.
Why do solid tumors respond poorly to chemotherapy?
Many cells are in G₀ phase, where chemo is ineffective.
List five mechanisms of drug resistance in cancer cells.
- ↓ Uptake 2. ↑ Efflux 3. ↓ Activation (prodrug) 4. ↑ Repair/↓ Target sensitivity 5. ↓ Apoptosis
What is the benefit of intermittent chemotherapy?
Allows normal cells to recover faster than cancer cells.
Why is combination chemotherapy used?
- ↓ Resistance 2. ↑ Cell kill 3. ↓ Injury to normal cells
What are the three major toxicities from bone marrow suppression?
- Neutropenia 2. Thrombocytopenia 3. Anemia
What digestive tract injuries are common in chemotherapy?
Stomatitis (inflammation of Oral Mucosa) and diarrhea.
Why are nausea and vomiting major concerns in chemotherapy?
They’re common, treatment-limiting, and require supportive care.
What are the two major classes of anti-cancer drugs?
- Cytotoxic agents 2. Hormonal/other agents
What is the difference between cell cycle phase-specific and non-specific drugs?
Specific: active phases only; Non-specific: any stage, more toxic to dividing cells.
Describe alkylating agents and their mechanism.
Cross-link DNA by alkylating guanine; phase non-specific; example: Cyclophosphamide. (Memory Tip: alkyline cyclone) , prodrug, and need liver conversion. Delay onset. Most common indication Hodgkin (hog = ugly bumps)
Describe platinum compounds and their mechanism.
Nonspecific, Cross-link DNA like alkylating agents and stop replication; example: Cisplatin; treat ovarian, testicular and advance bladder ca, side effects: nephro/ototoxicity + emetogenic (cisplatin NOE)
Describe antimetabolites and their subclasses.
Inhibit Specific enzymes or prevent DNA replication; Cell Cycle S-phase specific; subclasses: folic acid, purine(adenine, guanine), pyrimidine (cytosine, thymine, uracil) analogs.
How do antitumor antibiotics work?
Intercalate DNA to inhibit synthesis; nonspecific, IV only not oral, example: Anthracyclines; AE: cardiotoxic & Bone marrow impression
How do mitotic inhibitors work and what are their types?
Cell cycle specific, Inhibit mitosis; types: Vinca alkaloids (block metaphase)- bind to tubulin protein and cause inappropriate distribution of chromosomes, Taxanes (stabilize microtubules): work in late G2 phase, freeze microtubules and cannot mitosis.
