ONS/ONCC Chemotherapy &
Immunotherapy Certification Exam 2026
Practice Questions & Answers | Oncology
Nursing Review Guide with Detailed
Rationales
ONS/ONCC Chemotherapy & Immunotherapy Certification Exam 2026
Practice Questions & Answers | Oncology Nursing Review Guide
• This review guide contains 200 practice questions with detailed EXPERT
RATIONALE designed to mirror the actual ONS/ONCC certification exam format,
covering all core competencies tested.
• Study tip: Attempt each question independently before checking the correct
answer and EXPERT RATIONALE — this active recall method significantly improves
retention and exam performance.
QUESTION 1
A nurse is preparing to administer vesicant chemotherapy via a peripheral IV.
Which action is the highest priority before beginning the infusion?
A. Premedicate the patient with antiemetics
B. Verify the patient's allergy history
C. Confirm blood return and patency of the IV site
D. Educate the patient about side effects
E. Double-check the medication administration record
C. Confirm blood return and patency of the IV site
EXPERT RATIONALE: Vesicants cause severe tissue damage and necrosis if
extravasation occurs. Confirming blood return and IV patency before administering
a vesicant is the highest priority to prevent extravasation injury.
,QUESTION 2
Which chemotherapy agent is classified as a vesicant?
A. Cyclophosphamide
B. Methotrexate
C. Fluorouracil (5-FU)
D. Doxorubicin
E. Carboplatin
D. Doxorubicin
EXPERT RATIONALE: Doxorubicin (an anthracycline) is a classic vesicant.
Extravasation can lead to severe tissue necrosis. Cyclophosphamide and 5-FU are
irritants, while carboplatin is considered a non-vesicant.
QUESTION 3
A patient develops redness, swelling, and pain at the IV site during
doxorubicin infusion. What is the nurse's first action?
A. Apply a warm compress to the site
B. Slow the infusion rate
C. Stop the infusion immediately and disconnect the IV
D. Aspirate the remaining drug through the IV catheter
E. Notify the physician before taking any action
C. Stop the infusion immediately and disconnect the IV
EXPERT RATIONALE: Suspected extravasation requires immediate cessation of the
infusion. The nurse should stop the drug, leave the catheter in place temporarily to
aspirate residual drug, then follow the extravasation protocol. Applying heat is
contraindicated with anthracyclines.
,QUESTION 4
Which antidote is used to treat anthracycline extravasation?
A. Sodium thiosulfate
B. Hyaluronidase
C. Dexrazoxane (Totect)
D. Phentolamine
E. Leucovorin
C. Dexrazoxane (Totect)
EXPERT RATIONALE: Dexrazoxane is the only FDA-approved treatment for
anthracycline extravasation. It works by inhibiting topoisomerase II and reducing
free radical damage to surrounding tissue.
QUESTION 5
A nurse is caring for a patient receiving cisplatin. Which laboratory value
requires the most immediate attention?
A. Hemoglobin of 10.5 g/dL
B. Serum creatinine of 2.8 mg/dL
C. Platelet count of 120,000/mm³
D. Serum potassium of 3.4 mEq/L
E. White blood cell count of 4,500/mm³
B. Serum creatinine of 2.8 mg/dL
EXPERT RATIONALE: Cisplatin is highly nephrotoxic. An elevated serum creatinine
indicates renal impairment, which can lead to drug accumulation and toxicity.
Adequate hydration and renal monitoring are critical before and after cisplatin
administration.
, QUESTION 6
Which of the following best describes the mechanism of action of alkylating
agents?
A. They inhibit microtubule polymerization
B. They block topoisomerase II enzyme
C. They cross-link DNA strands, preventing replication
D. They inhibit dihydrofolate reductase
E. They bind to estrogen receptors on tumor cells
C. They cross-link DNA strands, preventing replication
EXPERT RATIONALE: Alkylating agents (e.g., cyclophosphamide, cisplatin,
carmustine) work by forming covalent bonds with DNA, creating cross-links that
prevent DNA replication and transcription, leading to cell death.
QUESTION 7
A patient is receiving high-dose methotrexate. Which rescue agent must be
available?
A. Mesna
B. Leucovorin (folinic acid)
C. Amifostine
D. Dexrazoxane
E. Ondansetron
B. Leucovorin (folinic acid)
EXPERT RATIONALE: Leucovorin rescues normal cells from methotrexate toxicity
by providing reduced folate, bypassing the dihydrofolate reductase inhibition
caused by methotrexate. Timing is critical — rescue must begin as scheduled.
Immunotherapy Certification Exam 2026
Practice Questions & Answers | Oncology
Nursing Review Guide with Detailed
Rationales
ONS/ONCC Chemotherapy & Immunotherapy Certification Exam 2026
Practice Questions & Answers | Oncology Nursing Review Guide
• This review guide contains 200 practice questions with detailed EXPERT
RATIONALE designed to mirror the actual ONS/ONCC certification exam format,
covering all core competencies tested.
• Study tip: Attempt each question independently before checking the correct
answer and EXPERT RATIONALE — this active recall method significantly improves
retention and exam performance.
QUESTION 1
A nurse is preparing to administer vesicant chemotherapy via a peripheral IV.
Which action is the highest priority before beginning the infusion?
A. Premedicate the patient with antiemetics
B. Verify the patient's allergy history
C. Confirm blood return and patency of the IV site
D. Educate the patient about side effects
E. Double-check the medication administration record
C. Confirm blood return and patency of the IV site
EXPERT RATIONALE: Vesicants cause severe tissue damage and necrosis if
extravasation occurs. Confirming blood return and IV patency before administering
a vesicant is the highest priority to prevent extravasation injury.
,QUESTION 2
Which chemotherapy agent is classified as a vesicant?
A. Cyclophosphamide
B. Methotrexate
C. Fluorouracil (5-FU)
D. Doxorubicin
E. Carboplatin
D. Doxorubicin
EXPERT RATIONALE: Doxorubicin (an anthracycline) is a classic vesicant.
Extravasation can lead to severe tissue necrosis. Cyclophosphamide and 5-FU are
irritants, while carboplatin is considered a non-vesicant.
QUESTION 3
A patient develops redness, swelling, and pain at the IV site during
doxorubicin infusion. What is the nurse's first action?
A. Apply a warm compress to the site
B. Slow the infusion rate
C. Stop the infusion immediately and disconnect the IV
D. Aspirate the remaining drug through the IV catheter
E. Notify the physician before taking any action
C. Stop the infusion immediately and disconnect the IV
EXPERT RATIONALE: Suspected extravasation requires immediate cessation of the
infusion. The nurse should stop the drug, leave the catheter in place temporarily to
aspirate residual drug, then follow the extravasation protocol. Applying heat is
contraindicated with anthracyclines.
,QUESTION 4
Which antidote is used to treat anthracycline extravasation?
A. Sodium thiosulfate
B. Hyaluronidase
C. Dexrazoxane (Totect)
D. Phentolamine
E. Leucovorin
C. Dexrazoxane (Totect)
EXPERT RATIONALE: Dexrazoxane is the only FDA-approved treatment for
anthracycline extravasation. It works by inhibiting topoisomerase II and reducing
free radical damage to surrounding tissue.
QUESTION 5
A nurse is caring for a patient receiving cisplatin. Which laboratory value
requires the most immediate attention?
A. Hemoglobin of 10.5 g/dL
B. Serum creatinine of 2.8 mg/dL
C. Platelet count of 120,000/mm³
D. Serum potassium of 3.4 mEq/L
E. White blood cell count of 4,500/mm³
B. Serum creatinine of 2.8 mg/dL
EXPERT RATIONALE: Cisplatin is highly nephrotoxic. An elevated serum creatinine
indicates renal impairment, which can lead to drug accumulation and toxicity.
Adequate hydration and renal monitoring are critical before and after cisplatin
administration.
, QUESTION 6
Which of the following best describes the mechanism of action of alkylating
agents?
A. They inhibit microtubule polymerization
B. They block topoisomerase II enzyme
C. They cross-link DNA strands, preventing replication
D. They inhibit dihydrofolate reductase
E. They bind to estrogen receptors on tumor cells
C. They cross-link DNA strands, preventing replication
EXPERT RATIONALE: Alkylating agents (e.g., cyclophosphamide, cisplatin,
carmustine) work by forming covalent bonds with DNA, creating cross-links that
prevent DNA replication and transcription, leading to cell death.
QUESTION 7
A patient is receiving high-dose methotrexate. Which rescue agent must be
available?
A. Mesna
B. Leucovorin (folinic acid)
C. Amifostine
D. Dexrazoxane
E. Ondansetron
B. Leucovorin (folinic acid)
EXPERT RATIONALE: Leucovorin rescues normal cells from methotrexate toxicity
by providing reduced folate, bypassing the dihydrofolate reductase inhibition
caused by methotrexate. Timing is critical — rescue must begin as scheduled.
