Practice Exam Questions And Correct

Certified Oncology Nurse Certification Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• The most common type of cancer among women in the United States

is

• Ovarian cancer
• Breast cancer
• Lung cancer
• Colorectal cancer

Rationale: Breast cancer remains the most common malignancy

diagnosed in women in the U.S., accounting for a significant proportion of cancer morbidity and mortality.

• Which chemotherapy agent is known to cause cardiotoxicity?
• Cyclophosphamide
• Doxorubicin
• Vincristine
• Methotrexate 1 / 4

Rationale: Doxorubicin, an anthracycline, causes dose-dependent

cardiotoxicity due to free radical formation leading to myocardial damage.

• The tumor marker CA-125 is primarily used in the diagnosis and

monitoring of

• Breast cancer
• Prostate cancer
• Ovarian cancer
• Pancreatic cancer

Rationale: CA-125 is a glycoprotein antigen elevated in many ovarian

cancers and used for monitoring disease progression.

• The TNM staging system classifies cancer based on
• Tumor size, nodal involvement, and metastasis
• Tumor size, nodal involvement, and metastasis
• Tumor histology only
• Cellular differentiation

Rationale: The TNM system describes tumor extent (T), lymph node

status (N), and distant metastasis (M) to determine overall cancer stage.

• A patient receiving cisplatin is at greatest risk for
• Hepatotoxicity
• Nephrotoxicity
• Ototoxicity 2 / 4

• Neuropathy

Rationale: Cisplatin causes nephrotoxicity due to accumulation in

renal tubular cells, requiring adequate hydration protocols.

• Which nursing intervention is essential during extravasation of a

vesicant chemotherapy drug?

• Apply warm compress
• Massage the area
• Stop the infusion immediately
• Flush the line with saline

Rationale: Immediate discontinuation of the infusion prevents

further tissue damage from vesicant leakage.

• Which symptom is most characteristic of anemia in a cancer patient?
• Nausea
• Fatigue
• Vomiting
• Pruritus

Rationale: Fatigue is the most common symptom of anemia due to

decreased oxygen delivery to tissues.

• A patient receiving radiation therapy to the head and neck is at risk for
• Diarrhea
• Mucositis
• Alopecia only
• Constipation 3 / 4

Rationale: Radiation to the head and neck commonly damages

mucosal cells, leading to mucositis and painful swallowing.

• What is the primary purpose of a bone marrow biopsy in oncology

care?

• To evaluate bone marrow function and detect malignant cells
• To monitor electrolyte levels
• To measure chemotherapy drug levels
• To assess renal function

Rationale: Bone marrow biopsy identifies hematologic malignancies

and marrow suppression status.

• The nadir period refers to
• The lowest point of a patient’s white blood cell count after

chemotherapy

• Peak plasma concentration
• Time of maximum nausea
• Period of tumor shrinkage

Rationale: Nadir indicates the period of greatest myelosuppression

and infection risk following chemotherapy.

• Which symptom indicates superior vena cava syndrome?
• Abdominal pain
• Hematuria
• Facial and upper extremity swelling
• Cyanosis of the feet
• / 4