Tips and tricks to

safely treat central lung tumors

Aman Sharma, M.D.

J. Nuyttens, M.D., Ph.D.

Disclosure & Disclaimer

An honorarium is provided by Accuray for this presentation

The views expressed in this presentation are those of the presenters and do not necessarily reflect the views or policies of Accuray Incorporated or its subsidiaries. No official endorsement by Accuray Incorporated or any of its subsidiaries of any vendor, products or services contained in this presentation is intended or should be inferred.

Definition of Central tumors

2 cm from …

Synchrony® Respiratory Tracking System

Tracking for tumors impacted by respiratory motion Patient wears a vest with optical markers that serve as a surrogate for tumor

position. Camera system monitors position of implanted fiducial markers.

Reducing margins ?

Population based margins (PBM) utilized to account for tumour motion were

typically 5 mm radially and 8–10 mm longitudinally.

For : CK: margins: GTV+5-7 mm = PTV

Reducing marginsITV based target volume Real-time tumor tracking

with the

CyberKnife® System

Reducing margins: how ?

Xsight® Lung System

Placing markers

endo-bronchoscopic

percutaneous intrapulmonary

intravascular

Endo-echo

Dose and dose volume constraints

Our fractionation schedules with MC

Central lung tumors : 11Gy * 5 fractions

For tumors close to esophagus or <6mm from pericardium : 7.5 Gy *7 fractions

Fractionation Schedules and Results

Close to esophagus:

6 *8 Gy -> 7*7 Gy

Close to main bronchi only:

5 * 9 Gy -> 5 * 10 Gy -> 5 *12 Gy

2yr Survival:

NSCLC -------53%

Metastases----75%

Nuyttens et al 2012

Use of appropriate BED

Nuyttens et al 2012

2-years LC

85% with a BED >100 Gy

60% BED <100 Gy.

Fractionation schedules and results

Nuyttens et al 2012

2-years LC

NSCLC ---------85%

Metastases ----64%

Dose to organs and toxicity

No severe acute or late toxicity Nuyttens et al 2012

Duijm et al 2016

Dose and Volume of the Irradiated Main Bronchi and Related Side Effects

N=134 690 bronchial structures delineated Bronchial structures divided1) (T) trachea2) (MI) mainstem bronchus and

intermediate bronchus 3) (UML) upper-, middle-, and lower- lobe

bronchi4) (SB) segmental bronchi (branches of

the upper-,middle-, and lower bronchi) Side effects scored1) stenosis2) occlusion without atelectasis in the

same segment3) occlusion with atelectasis in the same

segment.

Dose and Volume of the Irradiated Main Bronchi and Related Side Effects in the Treatment of Central Lung Tumors With Stereotactic Radiotherapy

Duijm et al 2016

No side effects found in the

trachea

Stenosis : main bronchus and

bronchus intermedius.

Higher grades of side effects

(occlusion and atelectasis) :

upper, middle and lower bronchi

and the segmental bronchi

Duijm et al 2016

Oesophagus toxicity

Nuy

ttens

, Sem

Rad

Onc

, 201

6

Primary Lung cancer & Pulmonay oligometastasis Dose 6*8 Gy Post RT (15 months)

Pre-RT

Post RT (30 months)• Dose: 6*8 Gy

Conclusions

Fractionation of 5 or more fractions with the CyberKnife® System is safe.

BED of ≥100Gy associated with excellent local control

Reducing margins is very import and so is the treatment associated with

no mortality, limited toxicity.

J. Nuyttens

J. Praag

R. De Boer

I. Antonisse

S. Aluwini

L. Baartman

N. Van der Voort

J-B. Prevost

M. Hoogeman

H. Marijnissen

E. De Klerck

L. Luthart

D. De La Bije

C. De Pan

H. Joosten