AOCNP Radiation Therapy Principles and Side Effects

Question 1

What is the primary mechanism by which ionizing radiation kills cancer cells?

Accepted Answer

Inducing DNA double-strand breaks leading to apoptosis or mitotic catastrophe

Answer

Radiation kills cells primarily through direct and indirect (free radical-mediated) DNA double-strand breaks. Cells unable to repair this damage undergo apoptosis, necrosis, or mitotic catastrophe. Rapidly dividing cells are most sensitive due to less time for DNA repair between divisions.

Question 2

Stereotactic body radiation therapy (SBRT) differs from conventional radiation in that SBRT delivers:

Accepted Answer

Ablative doses in 1–5 fractions with high precision

Answer

SBRT (also called SABR) delivers ablative doses (typically 25–60 Gy) in 1–5 fractions using highly conformal techniques (IMRT/VMAT with image guidance). It is used for early-stage lung cancer, liver metastases, spinal metastases, and other oligometastatic disease.

Question 3

Radiation recall is an acute dermatitis reaction triggered by certain chemotherapy agents administered after prior radiation. Which agent is most classically associated with radiation recall?

Accepted Answer

Doxorubicin (Adriamycin)

Answer

Radiation recall is an inflammatory skin reaction in a previously irradiated field triggered by certain drugs, most classically anthracyclines (doxorubicin), gemcitabine, taxanes, and capecitabine. It can occur weeks to years after radiation and may also affect internal organs.

Question 4

Which grading system is used by oncology nurses to assess and document radiation-induced side effects including mucositis and dermatitis?

Accepted Answer

CTCAE (Common Terminology Criteria for Adverse Events)

Answer

The CTCAE (published by NCI) is the standardized system for grading adverse events in oncology, grading toxicities from 1 (mild) to 5 (death). Radiation-induced dermatitis, mucositis, esophagitis, and other toxicities are all graded using CTCAE criteria.

Question 5

Total body irradiation (TBI) is most commonly used in what context?

Accepted Answer

Myeloablative conditioning prior to hematopoietic stem cell transplantation

Answer

TBI is a component of myeloablative conditioning regimens before allogeneic HSCT for hematologic malignancies. It destroys residual leukemic/lymphomatous cells, suppresses the immune system to prevent graft rejection, and ablates the bone marrow to create space for engraftment.

AOCNP - Advanced Oncology Certified Nurse Practitioner Practice Test

AOCNP - Advanced Oncology Certified Nurse Practitioner Practice Test

AOCNP Radiation Therapy Principles and Side Effects