FINAL EXAM NATIONAL BOARD OF EXAMINATIONS
JUNE 2018

POSSESSION/USE OF CELL PHONES OR ANY SUCH ELECTRONIC GADGETS IS NOT PERMITTED INSIDE THE EXAMINATION HALL.
RADIOTHERAPY
PAPER-I
RTH/J/18/41/I
Time: 3 hours
Max. Marks:100
Important Instructions:
Attempt all questions in order.
Each question carries 10 marks.
Read the question carefully and answer to the point neatly and legibly.
Do not leave any blank pages between two answers.
Indicate the question number correctly for the answer in the margin space
Answer all the parts of a single question together.
Start the answer to a question on a fresh page or leave adequate space between two answers.
Draw table/diagrams/flowcharts wherever appropriate.
Write short notes on:
1. Draw a schematic diagram of the lymphatic drainage of the:
Breast
Middle third of the esophagus
Left testis

2. Explain the physiologic mechanistic basis of:
Visual field defects in a patient with a right occipital glioma.
Mechanisms of breathlessness in a patient with
bronchogenic carcinoma.
Aspiration in a patient with oropharyngeal cancer, pre and
post radiotherapy.

3. What are the various phases of a clinical trial?
The need to define a patient population, randomization
stratification.
The need to define 'trial stopping rules', intention to treat
analysis per protocol analysis.

4. What is meant by:
True positive and False positive
Positive and Negative predictive value
Confidence interval
Odds ratio and Hazard ratio

5. Screening for cancer and its goal using one tumor site as an
example.
Evidence base and rationale for the frequency and
investigations during follow-up of a treated patient of early
breast cancer.
5+5
6. The distinction between beam modifying and beam direction.
Need for wedge filters in radiotherapy.
Enumerate methods by which a dose distribution identical to
that of a physical wedge filter can be created without using a
wedge filter.
What is meant by wedge angle and hinge angle and their
general guiding relationship?

P.T.O.
FINAL EXAM NATIONAL BOARD OF EXAMINATIONS
JUNE 2018

POSSESSION/USE OF CELL PHONES OR ANY SUCH ELECTRONIC GADGETS IS NOT PERMITTED INSIDE THE EXAMINATION HALL.
7. Percentage depth dose.
Factors influencing Percentage depth dose.
Mechanism that explains the location of Dmax and it variation
with various photon energies.
Field equivalence of rectangular fields for central axis depth
dose distribution.

8. Properties of an ideal brachytherapy source.
Why were radium substitutes required?
How are dose rates in brachytherapy binned together?
Compare HDR with LDR brachytherapy and the rational to
use these.

9. What is the rationale of the choice of prescription point
normalization method in:
Conventional 2 D radiotherapy planning
Intensity modulated radiotherapy
Radiosurgery

10. With regard to immobilization positioning devices:
Describe those in common use for various sites of the body.
What is the basic purpose of their use?
How do you calculate the precision of relocation?
How do you correct errors in relocation on the treatment
table?