1) The study evaluated the feasibility, tolerability, and patient-reported outcomes of using surface guided radiotherapy with breath-hold for stereotactic body radiotherapy treatment of liver metastases. 2) 41 patients with 51 liver lesions were treated with 3-5 fractions of radiation using breath-hold and surface guidance for motion management. Patient questionnaires indicated that breath-holding was tolerable and the training and equipment were clear. 3) Treatment times including setup and delivery averaged around 14 minutes per fraction when using surface guidance. Surface guidance helped identify intrafraction motion in a small number of patients who required additional imaging or expanded margins.

1. Feasibility and Tolerability of Surface Guided
Radiotherapy in Breath-Hold Liver
Stereotactic Body Radiotherapy
Menekşe Turna
Anadolu Medical Center-Turkey
01.12.2022-London

2. Introduction
• Intra-fractional motion is one of the main challenges in radiotherapy
• Breath-hold
• Reproducibility and consistency are critically important
• Surface guidance

3. Aim
• AlignRT system (Vision RT Ltd, London, UK)
• Varian EDGE
• Since 2018
• In this study, we aim to report patient-reported outcomes (PROMs),
feasibility and tolerability of surface guidance with breath-hold SBRT in a
specific subgroup: liver metastases.

4. Methods
• Liver metastases from different primaries
• Two different parts
• 1. Patient reported outcomes (PROMs)
• 2. Time analysis

5. PROMs
• Two step questionnaire with 7
questions.
• Scale from 1 to 4 points
• Assessment of:
• Patient’s experience of coaching
and information provided by staff.
• Patient’s comfort with use of the
device
• Personal levels of anxiety.
First questionnaire (Before planning CT)
1. Did you find the training you received before the breath-hold procedure helpful?
2. Was the equipment used during breath-hold clear and understandable?
3. Were the commands given by the technician understandable during breath-hold?
4. Was it challenging to hold your breath?
5. Was the CT scan time long?
6. Did you experience stress during the CT scan?
7. Were you worried because you took an active role in the CT scan?
Second questionnaire (After completion of Treatment)
1. Did you find the training you received before the breath-hold procedure helpful?
2. Was the equipment used during breath-hold clear and understandable?
3. Were the commands given by the technician understandable during breath-hold?
4. Was it challenging to hold your breath?
5. Was the treatment period long?
6. Did you experience stress during the treatment?
7. Were you worried because you took an active role in the treatment?

6. 1st Step 2nd Step
Planning CT
First
Questionnaire
3rd Step
4th Step
Contouring and
Treatment
Planning
5th Step
Treatment
Delivery
6th Step
Second
Questionnaire
Coaching before
simulation

7. Treatment Delivery
• Verbal and visual guidance.
• Tracking screen
• Setup: The reference surface created from planning CT.
• Monitoring during the treatment: New reference surface
in the treatment room
• User defined a region of interest (ROI)
• Rigid registration algorithm.
• Beams were stopped automatically
• (3 mm for translational and 2o for rotational)

8. Time Analysis
• •BH duration at least 10 seconds
• •Treatment time were recorded.
• •Any parameter that can affect treatment duration was analyzed
• Endpoints:
• 1. Tolerability
• 2. Feasibility and time analysis
• Prospective, single arm

9. RESULTS

10. Patient Characteristics
• Between April 2021- May 2022
• 41 patients and 51 lesions
• Total of 171 fractions.
• 21 female, 20 male.
• Median age was 60 (32-82)
• KPS 90 (70-100 range).
Primary site Colorectal 18
Breast 8
Lung 2
Uterus 2
Pancreatic 2
Others 9
Language Native 34
Non-Native 7
Presence of factors affecting lung
capacity
Yes 18
No 23
Previous BH history Yes 9
No 32
Lesion Number 1 34
2 5
3 1
4 1

11. Treatment details
• Patients were treated in 3 or 5 fractions.
• The median dose was 46,6 Gy (range
between 24-54 Gy).
Fraction number 3 17
5 24
Field (Arc) number 2 39
3 2
MV 6 37
10 4
PTV volume Median: 59,1 cm3 Range (9,5 -293,5
cm3
GTV volume Median: 21,7 cm3 Range (1,3-146,8
cm3)
Monitor Unit Median: 3081,6 Range(1812-5370)

12. Patient-reported outcome
First questionnaire (Before planning CT) 1-4 scale
1. Did you find the training you received before the breath-hold procedure helpful? 4
2. Was the equipment used during breath-hold clear and understandable? 3,9
3. Were the commands given by the technician understandable during breath-hold? 3,8
4. Was it challenging to hold your breath? 1,5
5. Was the CT scan time long? 1,1
6. Did you experience stress during the CT scan? 1,2
7. Were you worried because you took an active role in the CT scan? 1,2
Second questionnaire (After completion of Treatment) 1-4 scale
1. Did you find the training you received before the breath-hold procedure helpful? 4
2. Was the equipment used during breath-hold clear and understandable? 3,9
3. Were the commands given by the technician understandable during breath-hold? 3,9
4. Was it challenging to hold your breath? 1,6
5. Was the treatment period long? 1,4
6. Did you experience stress during the treatment? 1,5
7. Were you worried because you took an active role in the treatment? 1,2

13. Patient-reported outcome
• Training before CT simulation was beneficial.
• The equipment and the commands were understandable.
• Holding breath is tolerable.
• Treatment duration is not long.
• Patients have a little stress taking an active role in the treatment and
CT scan.

14. Treatment Duration
• CBCT: 2,6 BHs (2-5,7).
• CBCT period and evaluation time: 7,18 minutes (4,47-13,17).
• Treatment: 7,1 BHs (3.6-16.3).
• Treatment time:14,4 minutes (9,1- 24,6).
• Average beam on time: 7,23 minutes (1,44-16,43).

15. Treatment Duration without SGRT
CORRELATION OF DIFFERENT PARAMETERS WITH QA TIME
Test Coefficient p
MU
Pearson 0,899 <0,001
Partial (control - doz hızı) 0,939 <0,001
DOSE PER FRACTION Pearson 0,598 <0,001
DOSE RATE Pearson -0,357 0,022
PTV VOLUME Spearman -0,209 0,19

16. BOT W SGRT / BOT WO SGRT (QA)
Test Coefficient p
GENDER Nokta Çift Serili Korelasyon Analizi 0,371 0,02
KPS
LANGUAGE Nokta Çift Serili Korelasyon Analizi -0,252 0,112
PRESENCE OF FACTORS
AFFECTING LUNG CAPACITY Nokta Çift Serili Korelasyon Analizi -0,211 0,185
PREVIOUS BH HISTORY Nokta Çift Serili Korelasyon Analizi -0,001 0,997
LUNG VOLUME Pearson -0,028 0,863ND
AGE Pearson -0,009 0,955ND

17. SGRT
Movement recognized by SGRT
a. Second CBCT: 7 patients (one fraction)
1 patient (two fractions)
b. Gating margin expantion: 5 patients (all fractions)
2 patients (one fraction)
c. Align RT deactivation: 1 patient in 1 fraction

18. Conclusion
• BH Liver SBRT with SGRT;
• Tolerable for patients.
• Pre-treatment education is important and useful.
• Intrafractional motion can be noticed with SGRT and additional action
may be required in some patients.
• With the addition of SGRT, BH SBRT can be administered in a
reasonable time.