1. 10th Annual Lung Cancer Conference Radiation Oncology
Advances in Radiation Oncology for Lung Cancer Treatment
John Mansueti, MD
PRMC Radiation Oncology
12 Mar, 2015 1

2. Disclosures
None, but always looking!

3. Objectives
Describe the role of 4-dimension (4-D) CT scanning in radiation lung treatment planning.
Describe the two techniques of stereotactic body radiation therapy: Non-coplanar Intensity Modulated Radiation Therapy and Volumetric Modulated Arc Therapy.
Compare the expected local control rates for early stage lung cancer with SBRT and surgery.

5. What is Radiation Therapy?
Using ionizing radiation to achieve lethal damage to target tissues
The radiation causes lethal breaks in the cells DNA

6. Linear Accelerator (LINAC)
Delivers high energy X-Rays (photons) or electrons to the patient’s tumor
Our treatment plans try to maximize dose to the tumor while minimizing dose to normal tissue
Modern techniques include IMRT, IGRT, SRS, SBRT

7. How does a LINAC Work
Microwaves accelerate electrons to extremely high speeds and slam them into a metal target
High energy x-rays are produced by this collision
The x-rays are shaped using several methods as they exit the machine to conform to the target

8. Why do we need SBRT? LC with SBRT is 92-97% Radiation Modality
5-year Overall Survival
Conventional RT
20%
SBRT
42%
Radiother Oncol 2010

9. Problem Lung tumors move a lot with respiration
≈40% lung tumors move >0.5cm
≈10-15% lung tumors move >1.0cm
How can we target a lung tumor more accurately with tight margins to minimize toxicity to normal lung?

10. Advanced Imaging
4-D CT scan
4-D PET/CT
Cone Beam CT
MRI Fusion

11. 4-D CT Scan
Advances in technology have made CT scanning much faster and accurate
Traditional CT scan only images the tumor at one point of the breathing cycle
Many 3-D CT sets are obtained corresponding to a particular breathing phase

12. 4D CT

13. 4-D CT Scan
Over-sampling images at every position of interest along the patients axis
Images are tagged with breathing signals
Images are sorted retrospectively based on corresponding breathing signal

14. MIP (Maximum Intensity Projection)
MIP reduces the multiple 3-D CT images from a 4-D data set into a single 3-D data set
MIP represents the maximum intensity encountered by the corresponding voxels in all the individual 3-D phase image sets of the 4-D image set.

15. MIP
CT Slice
MIP

16. MIP

17. MIP

18. Cone Beam CT
Acquires real-time 3D images of the patient while on the treatment table with a single rotation of the gantry
Patient can be adjusted immediately to align tumor target
Response of tumor to treatment can be monitored

19. Cone Beam CT

20. CT-PET/CT Fusion

21. Optimal Radiation Treatment
Encompass the tumor with a very conformal dose cloud with rapid dose fall-off outside your target
Minimize tumor motion to allow smaller treatment field, thus minimizing dose to normal tissue
Verify patient positioning with immediate imaging

22. Modern Techniques IMRT-Intensity Modulated Radiation Therapy
VMAT-Volumetric Arc Therapy
IGRT-Image Guided Radiation Therapy
SBRT-Stereotactic Body Radio-Therapy

23. SBRT
Advances in hardware (imaging), software innovation (computational algorithms), and faster computer processors have enable development of SBRT techniques.
SBRT involves highly precise, high dose, short course treatments (3-5 fractions)
SBRT allows precise targeting and techniques to minimize tumor motion

24. Multiple Treatment Directions

25. Highly Conformal Dose

26. Critical Structures Avoided

27. RapidArc
VMAT (Volumetric Modulated Arc Therapy) is a new radiation technique using sophisticated treatment plan to deliver a continuous beam (arc) of radiation as the linear accelerator rotates around patient

28. RapidArc
Planning optimization algorithm that simultaneously changes 3 parameters during treatment
Shape of treatment aperture
delivered dose intensity
Speed of gantry rotation
Treatment time is very rapid

29. RapidArc Conformal Dose

30. RapidArc Conformal Dose

31. Patient E.D.
68 y/o M was found to have a left sided pulmonary nodule after presenting with cough
Biopsy Lung Adenocarcinoma
Plan: 4800 cGy in 4 fractions (1200 cGy per fraction)

32. Local obliteration CT CT

33. Patient A.H.
78 F had a COPD exacerbation and imaging in Jan 2012 revealed RLL nodule
Biopsy: Lung Adenocarcinoma
Plan: 5400 cGy in 3 fractions

34. CT February 2013
CT March2014

35. Patient E.M.
73 y/o M with hx of LUL NSCLC s/p resection in 2011 with new RUL 2cm nodule in Jan 2013 (PET hot 5.3 SUV)
Biopsy caused penumothorax and path showed atypical cells
Plan: 5000 cGy in 5 fractions (1000 cGy per fraction)

36. CT CT

37. SBRT Results
Phase 2 multicenter study of 59 pts with T1 or T2 inoperable early stage tumors (medical condition precluded resection)
3 SBRT treatments (18Gyx3=54 Gy)
Local control 97%
Local/Regional Control 87%
3-year OS 56%
Median OS 48 months
Timmerman et al., JAMA 2010

38. Summary
Advanced Imaging has revolutionized targeting in Radiation Oncology
Modern radiation techniques have enabled dose escalation and excellent local control
SBRT is an excellent option for patients who are not surgical candidates or refuse surgery

39. QUESTIONS?