FRCR FRCR Clinical Oncology 2

Question 1

In brachytherapy, what does 'high dose rate' (HDR) mean?

Accepted Answer

Dose rate >12 Gy/hour at the reference point

Answer

HDR brachytherapy delivers dose at rates exceeding 12 Gy/hour, allowing outpatient treatment with no radiation exposure to staff after source retraction.

Question 2

Which lymphoma subtype is most radiosensitive and has the highest cure rate with radiotherapy alone in early-stage disease?

Accepted Answer

Classical Hodgkin lymphoma

Answer

Classical Hodgkin lymphoma is highly radiosensitive, and early-stage disease is commonly treated with combined modality therapy including involved-site radiotherapy.

Question 3

Proton therapy differs from conventional photon therapy primarily because:

Accepted Answer

Protons deposit most energy at the Bragg peak with minimal exit dose

Answer

The Bragg peak allows proton beams to deposit their maximum dose at a specific depth, then stop, dramatically reducing exit dose to tissues beyond the tumor.

Question 4

What is the primary mechanism of radiation-induced DNA damage that leads to cell death?

Accepted Answer

Double-strand DNA breaks

Answer

Double-strand DNA breaks are the most lethal form of radiation-induced damage because they are difficult to repair faithfully and can lead to chromosomal aberrations.

Question 5

Total body irradiation (TBI) is most commonly used as conditioning for:

Accepted Answer

Hematopoietic stem cell transplantation

Answer

TBI eliminates residual malignant cells and suppresses the immune system prior to bone marrow or stem cell transplantation.

FRCR - Fellow of the Royal College of Radiologists Practice Test

FRCR - Fellow of the Royal College of Radiologists Practice Test

FRCR FRCR Clinical Oncology 2