Treatment Efficiency and Optimization of

Patient Care with IBA ProteusOne

Terry Wu, Ph.D.

Chief Physicist, Radiation Oncology Department

Willis-Knighton Cancer Center/Proton Therapy Center

Shreveport, LA, USA

Willis-Knighton Cancer Center/Proton Therapy Center

Willis-Knighton Health System

4 Hospitals in Shreveport/Bossier City, Louisiana

1100 Bed – 4 Hospitals in

Shreveport/Bossier City, Louisiana

Cancer Center Opened in 2000

Radiation Therapy- early users of

Peacock IMRT, Tomotherapy,

Varian Linacs with OBI/CBCT

Willis-Knighton Radiation Oncology

900 patients per year, 90 patients per day and 500

Brachytherapy procedures per year

2 Elekta Versa Linacs, Tomotherapy, Nucletron HDR

and IBA ProteusOne

5 physicians, 5 physicists, 2 physics residents, 3

dosimetrists and numerous therapists

Staff adding specifically for proton

– 1.5 Physicist, 1 Dosimetrist, 3 Therapists & 2 Office assistants

IBA ProteusOne Project Timeline

Entered Negotiations May 2011

Contract Signed Sep. 2011

Groundbreaking Feb. 2012

Cyclotron Arrival Aug. 2013

Gantry Arrival Oct. 2013

Started Beam Tuning Dec. 2013

Started PBS Calibration Feb. 2014

Acceptance Test and Commission July 1st, 2014

First Patient Treated Sept. 9th, 2014

CBCT Installed Sept. 24th, 2015

CBCT LFOV Upgraded Jun. 30th , 2017

More than 500 patients treated Sept. 20th , 2018

To Date Proton Treatment StatisticsMore Then 500 Patients Treated

Re-treat – 8%

GU-Prostate43%

Brain15%

H/N10%

Lung9% GI

7%

GU-GYN5%

Breast/CW4%

Lymphoma2%

Spine1%

Sacroma2%

GU-other1%Other

6%

Unique Design of ProteusOne

Open Gantry Environment

– 220 degree

– Ambient Experience

Imaging Solutions

– Instantaneous on-board oblique imaging

– On-board CBCT with various FOV

Beam Delivery Modality

– Pencil beam scanning (PBS) only

– Treatment field size 20x24cm2

– Remote operation of accessories

ProteusOne Technology

Beam Energy 70-230 MeV

Range in Patient 0.1 - 32 g/cm2

Dose Rate 2 Gy/min (10x10x10 cm3)

Beam Sigma 3.5 & 4.7 mm at Range 32 & 15 g/cm2

6 Degree Robotic Couch

Energy Layer Switching Time ~0.9 sec

Compact (Open) Gantry Design

220 Degree Compact Gantry

180 Deg

90 Deg

0 Deg-35 Deg

-5 Deg

6 Degree Robotic Couch

ProteueOne Imaging SystemFixed Imaging System at Isocenter

Stereo ObliqueNozzle Imager

(CBCT&Ortho)

X-Ray Source Flat Panel

Stereo X-ray

Flat Panels

X-Ray Tube

Under Ground

ProteueOne Imaging System Specification

Specifications Stereo Oblique Nozzle Imager

Flat Panel Type Amorphous silicon Amorphous silicon

Image Mode 2D 2D, 3D

Scan Diameters (FOV) n/a 25cm (currently)

Scan Length (S-I FOV) n/a 26 cm

Source to Axis Distance 250 cm 100 cm

Imager to Axis Distance 82 cm 55 cm

Flat Panel Array 1440 x 1560 px 2881 x 2881 px

Flat Panel Physical Size 38.0 x 32.8 cm2 50.8 x 51.8 cm2

Panel Sensitive Area at

ISO22 x 20 cm2 28 x 28 cm2

Pixel Size at Isocenter 0.1 mm 0.1 mm

Max. Gantry Speed (CBCT) n/a 3, 6 deg/s

CBCT Frame Rate n/a 7.5 fr/s

Elekta Versa XVI

Amorphous silicon

2D, 3D and 4D

27, 41 & 50 cm

Up to 27cm

100 cm

54 cm

1024 x 1024 px

42.5 x 42.5 cm2

27 x 27 cm2

0.25 mm

6 deg/s

5.5 fr/s

ProteusOne Imaging System – CBCT Dose

13

Scan

ProtocolFOV

(Field of View)

Acquisition

Angle

Gantry

Speed (°/s)

Scan Parameters CTDIweighted

(mGy)kVp mA ms

Head HD Small 205 3 100 25 12 8.2

Head SD Small 205 6 100 25 12 4.4

Thorax Small 205 3 110 25 12 6.4

Pelvis Small 205 3 120 40 12 12.5

AI 2.0 (Large FOV)

Thorax Large434

(dual half scan)6 110 50 12 10.6

Pelvis Large434

(dual half scan)6 120 64 12 15.7

WK Imaging Protocol

Treatment SiteImage Modality Daily 2nd Field

VerificationStereo Oblique CBCT

Brain V A Y

Head/Neck V A Y

Thorax/Lung V A Y*

Breast/Chest Wall V A Y*

Abdomen V A Y*

Pelvis V A Y**

Prostate A & V A Y**

Prostate Bed V A Y*

Extremities A & V A Y*

– A: Patient Position Alignment – *: Only when couch moved

– V: Patient Position Verification – **: 5 days evaluation

Remote Operation

All mechanical and imaging systems can be activated from

either inside or outside the room

No need to enter the room between fields or isocenters

Significantly increases the efficiency of workflow

Multiple in-room cameras system prevents any possible

collision during treatment from remote operation

4 viewing

Cameras

Open Environment and Ambient Experience

The relaxing and welcome

atmosphere provided by an

open gantry environment and

ambient experience allows

for fast patient loading and

positioning

Open Environment and Ambient Experience

The relaxing and welcome

atmosphere provided by an

open gantry environment and

ambient experience allows

for fast patient loading and

positioning

Open Environment and Ambient Experience

The relaxing and welcome

atmosphere provided by an

open gantry environment and

ambient experience allows

for fast patient loading and

positioning

Fast and Efficient Workflow Achieves by

Integrating the Following Systems

220 Degree Open Gantry

6 Degree Robotic Couch

IBA Image-Guided System

– 2D Stereoscopic Oblique X-ray and 3D CBCT systems

Remote Operation

Multiple In-room Camera Monitoring System

Open Environment and Ambient Experience

Record and Verify System – Elekta Mosaiq

Four Common Clinical Cases to Demonstrate the

Efficient Treatment Workflow with ProteusOne

Simple – Prostate

Intermediate – Brain/Head&Neck

Advance – Lung

Challenge – Breast/Chest Wall

ProstateStandard Opposed Lateral Beams

Gantry is at fixed lateral position. Couch has to rotate 180 deg to treat

the opposed side (75 sec).

Use Stereo imaging to align with fiducial markers daily and CBCT to

check bladder filling and rectal balloon position weekly

Stereo imaging allows quick and accurate patient position confirmation

and monitoring after each couch movement

Level of Difficulty for setup and treatment Simple

Robotic Couch Yes

3D CBCT Weekly, SFOV (2 mins)

Stereo X-ray Yes, avg. 2 sets per field (1 min)

Remote Operation of Accessories Yes

# of time re-enter treatment room during treatment 0

Overall treatment time, including patient set up, imaging

guidance and electronic charting

12-15 minutes

Stereo Oblique

CBCT

CBCT

Brain2-3 non-coplanar SFUD fields

Open gantry provides no limitation for any non-coplanar beam.

No short couch top needs to switch. No limit of any SSD setup

CBCT with SFOV is the best imaging system to align

Use Stereo X-ray to confirm patient position after each couch

movement

Treating a vertex field is easy compared with closed gantry

Level of Difficulty for setup and treatment Intermediate

Open Gantry Advantage Yes

Robotic Couch Utilization Yes

3D CBCT Daily, SFOV (2 mins)

Stereo X-rays Yes, each couch movement

Remote Operation of Accessories Yes

# of time re-enter treatment room during treatment 0

Overall treatment time includes set up, image guidance,

treatment and electronic charting

15-20 minutes

Stereo CBCT

Head and Neck

3 coplanar IMPT fields (LAO, RAO &PA)

Open gantry environment and ambient experience offers faster patient loading and

positioning

CBCT with SFOV is the best imaging system for initial patient setup alignment

Use Stereo x-ray to confirm positioning after each couch movement

Level of Difficulty for setup and treatment Intermediate

Open Gantry Advantage Yes

Robotic Couch Utilization Yes

3D CBCT Daily, SFOV (2 mins)

Stereo X-rays Yes, each couch movement

Remote Operation of Accessories Yes

# of time re-enter treatment room during treatment 0

Overall treatment time includes set up, image

guidance, treatment and electronic charting

15-20 minutes

TPS Planning CBCT

LungEither Breath-Hold (BH) or Free-Breathing (FB) treatment

For BH, Qfix SDX system is used to ensure the correct and consistent level of

deep inspiration

4D-robust optimization with Monte Carlo dose calculation for planning

Acquire CBCT (with pause and resume function for BH) for initial patient setup

and stereo images for verification after each couch movement.

Utilize both layer and volumetric repainting for treating moving target

Level of Difficulty for setup and treatment Advance

Open Gantry Advantage Yes

Robotic Couch Utilization Yes

3D CBCT Daily (either SFOV, 2 mins or

LFOV 3 mins)

Stereo X-rays After each couch movement

Remote Operation of Accessories Yes

# of time re-enter treatment room during treatment 0

Overall treatment time includes set up, image guidance,

treatment and electronic charting

20-25 minutes

Lung

CBCT

re-CT and re-Plan

Planning CT

Daily CBCT triggers for

re-CT and re-plan due to

tumor volume and other

structure changes

during treatment

Left Chest Wall and Supra-Clavicular

Using CBCT and Stereo Oblique

Imaging Systems

A CASE STUDY

Left Chest Wall and Supra-Clavicular

with ProteusOne PBS System

Concerns

– Field size limitation

– 2 or 3 enface fields

– Field matching

– Multi-isocenter

– No light field and ODI

– IGRT

– Workflow

Three Field Matching Treatment

1st field: ISO#1, LAO medial CW, G=15°

2nd field: ISO#2, LAO lateral CW, G=55°

3rd field: ISO#3, AP s’clav, G=0°

Field Matching Using Gradient

Optimization Technique

• Overlapping fields by creating

a gradient penumbra from

RayStation TPS

Site-setup in Mosaiq

This is

CRITICAL!!

Manually enter ISO #1

information into reference CT

image in Mosaiq Site Setup

Daily Treatment Workflow

Breast/Chest Wall

Align patient

• lasers

1st field

• CBCT (ISO #1)

• Treat

2nd field

• Auto move to ISO #2

• Oblique verification

• Treat

3rd field

• Auto move to ISO #3

• Oblique verification

• Treat

30 – 40 minutesPt step in Pt step out

1) CBCT using ISO #1

in Site Setup

2) Check Mosaiq 1st field

definition and Treatment

Daily Treatment Workflow

4) Confirm 2nd field position (ISO

#2) using stereo oblique images

and treat

2nd Mosaiq

field definition

3) Use auto couch

movement to ISO #2

with pre-determined

relative couch position

from TPS

6) Confirm the final field

position (3rd field) and Treat

3rd Mosaiq

field definition

5) Auto couch movement

again to ISO #3

Left Chest Wall and Supra-Clavicular

Overall treatment procedure can be completed

in 30-40 minutes.

Post Treatment Field Verification

Relative treatment position for each field can be

verified in Mosaiq

Site Setup ISO #1 ISO #2 ISO #3

Breast/ Chest Wall

Integration with Mosaiq, remote operation and setup automation play a

major role to increase workflow efficiency

Level of Difficulty for setup and treatment Challenge

Open Gantry Advantage Yes

Robotic Couch Utilization Yes

3D CBCT Daily, either SFOV or LFOV

Stereo X-rays When move to next isocenter

Remote Operation of Accessories Yes

# of time re-enter treatment room during treatment 0

Overall treatment time includes set up, image guidance, treatment

and electronic charting

30-40 minutes

Fast and Efficient Treatment Workflow

with ProteusOne

Simple – Prostate (12-15 mins)

Intermediate – Brain/Head&Neck (15-20 mins)

Advance – Lung (20-25 mins)

Challenge – Breast/Chest Wall (30-40 mins)

Current Status

of the WK ProteusOne

TPS: Raystation 7.0; R&V: Mosaiq 2.6.4

31 patients treated on August 3, 2018 from 7:28am to 6:48pm (11.3 hours)

– 16 prostate, 3 lung, 4 brain, 5 H&N, 1 anal/rectum, 1 lymphoma, and 1 chest

wall

Morning QA starts at 6:30am

Average proton treatment takes about 16 minutes per patient (range from

12 to 30 minutes)

Average 2.4 fields per patient for treatment

Current up-time is 97.7% since Sept. 9th, 2014

Conclusion

With over 500 proton treatment experiences since 2014, Willis-

Knighton Proton Therapy Center has shown the open gantry

feature combined with volumetric CBCT and stereo image

guidance can be safely and efficiently delivered to a wide range of

body sites.

The open gantry design allows to large variety of treatments.

Furthermore, the open gantry environment shows advantage

when dealing with non-coplanar fields and offers the most efficient

workflow.