Chemotherapy of malignancy is a core subject for B. Pharm students, covering principles, mechanisms and clinical examples of antineoplastic drugs. This introduction highlights drug classes, pharmacokinetics, cell cycle specificity, mechanisms of action, patterns of toxicity, mechanisms of resistance and key supportive measures. Emphasis is placed on rational combination therapy, dose intensity, therapeutic index and examples such as alkylating agents, antimetabolites, anthracyclines, vinca alkaloids, taxanes, platinum compounds and targeted agents. Understanding drug interactions, rescue agents (mesna, leucovorin), management of tumor lysis syndrome and the role of growth factors is essential for safe chemotherapy practice. Now let’s test your knowledge with 30 MCQs on this topic.
Q1. Which is the primary mechanism of action of classical alkylating agents such as nitrogen mustards?
- Inhibition of thymidylate synthase
- Covalent alkylation causing DNA cross-linking
- Topoisomerase I inhibition
- Microtubule stabilization
Correct Answer: Covalent alkylation causing DNA cross-linking
Q2. Antimetabolites like methotrexate and 5-fluorouracil are most active during which cell cycle phase?
- G0 (resting phase)
- G1 phase
- S phase
- M phase
Correct Answer: S phase
Q3. Cyclophosphamide requires metabolic activation. Where and by what is it activated to its cytotoxic metabolite?
- Activated in plasma by esterases
- Activated in tumor cells by thymidylate synthase
- Activated in the liver by cytochrome P450 enzymes to phosphoramide mustard
- Activated in the kidneys by dehydrogenases
Correct Answer: Activated in the liver by cytochrome P450 enzymes to phosphoramide mustard
Q4. Which chemoprotective agent is routinely used to prevent hemorrhagic cystitis caused by ifosfamide?
- Leucovorin (folinic acid)
- Mesna (sodium 2-mercaptoethane sulfonate)
- Dexrazoxane
- Allopurinol
Correct Answer: Mesna (sodium 2-mercaptoethane sulfonate)
Q5. Which drug is used as a ‘rescue’ agent to mitigate high-dose methotrexate toxicity?
- Filgrastim (G-CSF)
- Leucovorin (folinic acid)
- Mesna
- Rasburicase
Correct Answer: Leucovorin (folinic acid)
Q6. 5-Fluorouracil (5-FU) exerts its antitumor effect primarily by inhibiting which enzyme?
- Dihydrofolate reductase
- Thymidylate synthase
- Topoisomerase II
- DNA-dependent RNA polymerase
Correct Answer: Thymidylate synthase
Q7. Which of the following adverse effects is most characteristically associated with doxorubicin (an anthracycline) at cumulative doses?
- Nephrotoxicity
- Cardiomyopathy leading to congestive heart failure
- Interstitial pneumonitis
- Hemorrhagic cystitis
Correct Answer: Cardiomyopathy leading to congestive heart failure
Q8. Which agent is used to reduce doxorubicin-induced cardiotoxicity by chelating iron and reducing free-radical formation?
- Dexrazoxane
- Amifostine
- Mesna
- Allopurinol
Correct Answer: Dexrazoxane
Q9. What is the major dose-limiting toxicity of cisplatin that requires aggressive hydration and monitoring?
- Cardiotoxicity
- Nephrotoxicity
- Severe peripheral neuropathy
- Pulmonary fibrosis
Correct Answer: Nephrotoxicity
Q10. Carboplatin dosing is commonly calculated using the Calvert formula. Which pharmacokinetic parameter is required by this formula?
- Area under the plasma concentration-time curve (AUC) and glomerular filtration rate (GFR)
- Half-life and protein binding percentage
- Volume of distribution and hepatic clearance
- Minimum inhibitory concentration (MIC)
Correct Answer: Area under the plasma concentration-time curve (AUC) and glomerular filtration rate (GFR)
Q11. Vinca alkaloids (vincristine, vinblastine) exert cytotoxicity primarily by which mechanism?
- Inhibiting microtubule polymerization leading to metaphase arrest
- Stabilizing microtubules and preventing depolymerization
- Intercalating into DNA and preventing replication
- Inhibiting dihydrofolate reductase
Correct Answer: Inhibiting microtubule polymerization leading to metaphase arrest
Q12. Taxanes (paclitaxel, docetaxel) differ from vinca alkaloids because they:
- Inhibit topoisomerase I
- Stabilize microtubules and prevent depolymerization
- Cause alkylation of DNA bases
- Are exclusively S-phase specific
Correct Answer: Stabilize microtubules and prevent depolymerization
Q13. Which toxicity is classically associated with vincristine and may limit its use?
- Myelosuppression with profound neutropenia
- Severe peripheral neuropathy and constipation due to autonomic dysfunction
- Cardiotoxicity
- Nephrotoxicity
Correct Answer: Severe peripheral neuropathy and constipation due to autonomic dysfunction
Q14. Irinotecan’s active metabolite SN-38 causes which characteristic dose-limiting toxicity that requires specific management?
- Severe mucositis only
- Early cholinergic syndrome and late severe diarrhea managed with atropine and loperamide respectively
- Delayed cardiomyopathy
- Ototoxicity
Correct Answer: Early cholinergic syndrome and late severe diarrhea managed with atropine and loperamide respectively
Q15. Tumor lysis syndrome can cause life-threatening hyperuricemia. Which agent enzymatically converts uric acid to allantoin and is useful in established TLS?
- Allopurinol
- Probenecid
- Rasburicase
- Febuxostat
Correct Answer: Rasburicase
Q16. Methotrexate inhibits which enzyme, leading to depletion of thymidine and impaired DNA synthesis?
- Thymidylate synthase
- Dihydrofolate reductase (DHFR)
- Ribonucleotide reductase
- Topoisomerase II
Correct Answer: Dihydrofolate reductase (DHFR)
Q17. Etoposide and doxorubicin share cytotoxic effects by targeting which cellular enzyme/process?
- Microtubule polymerization
- Topoisomerase II inhibition causing DNA strand breaks
- Inhibition of nucleotide salvage pathways
- Mitochondrial DNA synthesis inhibition
Correct Answer: Topoisomerase II inhibition causing DNA strand breaks
Q18. Overexpression of P-glycoprotein (MDR1 gene product) in tumor cells causes resistance by which mechanism?
- Enhanced DNA repair
- Increased drug efflux reducing intracellular drug accumulation
- Inactivation of drug by conjugation
- Mutation in drug target enzyme
Correct Answer: Increased drug efflux reducing intracellular drug accumulation
Q19. Which cytotoxic agent is most characteristically associated with profound myelosuppression and requires frequent blood count monitoring in acute leukemias?
- Cisplatin
- Cytarabine (Ara-C)
- Bleomycin
- Vincristine
Correct Answer: Cytarabine (Ara-C)
Q20. Which chemotherapeutic agent is well known to cause pulmonary fibrosis as a serious adverse effect?
- Bleomycin
- Daunorubicin
- Oxaliplatin
- 5-Fluorouracil
Correct Answer: Bleomycin
Q21. High inspired oxygen concentrations can exacerbate toxicity of which anticancer drug during anesthesia or oxygen therapy?
- Doxorubicin
- Bleomycin
- Cyclophosphamide
- Vinblastine
Correct Answer: Bleomycin
Q22. Which of the following agents is considered cell cycle non-specific and can kill resting as well as dividing tumor cells?
- Fluorouracil (5-FU)
- Bleomycin
- Cyclophosphamide
- Cytarabine
Correct Answer: Cyclophosphamide
Q23. 6-Mercaptopurine (6-MP) requires activation by which enzyme to become incorporated into nucleic acids?
- Xanthine oxidase
- Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
- Dihydrofolate reductase
- Glutathione S-transferase
Correct Answer: Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
Q24. Concurrent use of allopurinol with which chemotherapeutic agent necessitates a dose reduction due to impaired drug metabolism?
- 5-Fluorouracil
- 6-Mercaptopurine (6-MP) / Azathioprine
- Paclitaxel
- Bleomycin
Correct Answer: 6-Mercaptopurine (6-MP) / Azathioprine
Q25. Hemorrhagic cystitis is a known complication of which chemotherapeutic agent, due to the metabolite acrolein?
- Ifosfamide and cyclophosphamide
- Cisplatin
- Vincristine
- Methotrexate
Correct Answer: Ifosfamide and cyclophosphamide
Q26. Imatinib is a targeted therapy that inhibits which oncogenic tyrosine kinase fusion protein commonly seen in chronic myeloid leukemia?
- HER2/neu
- BCR-ABL
- EGFR mutant T790M
- ALK fusion protein
Correct Answer: BCR-ABL
Q27. Trastuzumab targets HER2-positive breast cancer but requires monitoring for which organ toxicity?
- Renal failure
- Cardiotoxicity (reduced left ventricular ejection fraction)
- Hepatic necrosis
- Severe pulmonary fibrosis
Correct Answer: Cardiotoxicity (reduced left ventricular ejection fraction)
Q28. Rituximab exerts antitumor effects primarily by binding to which antigen on B cells?
- CD20
- CD3
- HER2
- VEGF receptor
Correct Answer: CD20
Q29. The concept of dose-dense chemotherapy is based on which pharmacologic/biologic principle?
- Giving higher single doses at longer intervals to increase peak concentration
- Reducing cumulative dose to minimize toxicity
- Shortening intervals between cycles to prevent tumor regrowth and maximize cell kill (increase dose intensity)
- Administering drugs only during G0 phase to target resting cells
Correct Answer: Shortening intervals between cycles to prevent tumor regrowth and maximize cell kill (increase dose intensity)
Q30. One rationale for using combination chemotherapy regimens is to:
- Use drugs with identical mechanisms to amplify a single pathway
- Combine drugs with overlapping toxicities to ensure dose reductions
- Employ agents with different mechanisms and non-overlapping toxicities to enhance tumor kill and reduce resistance
- Avoid supportive care measures
Correct Answer: Employ agents with different mechanisms and non-overlapping toxicities to enhance tumor kill and reduce resistance
I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.
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