1. Surgery remains gold standard for early stage lung cancer
Current
Gold
Standard
Surgery remains gold standard for early stage lung cancer
Many patients cannot or prefer to not undergo surgery
SBRT/ SABR is emerging, improving alternative
Problem
Radiosurgery targets only primary tumor
Control at 1O site excellent
But +/- 15% recur regionally (with T1& T2 patients, adequate follow up, imaging at follow-up & actuarial method)
Concept Under Investigation
Identify regions at highest risk of micro-metastatic disease
Deliver ablative radiation to primary nodal drainage 1

2. Pulmonary Interstitial Lymphography
--Sedate patient with versed/ etc
--sterile prep and drape
--local anesthetic with injection of 1% lidocaine
--percutaneous insertion of co-axial introducer needle
--gain access to primary tumor with CT fluoro
--obtain biopsy
--then insert needle attached to syringe with iodinated contrast material
--Inject 1-2 cc over 60 secs
--Begin timer and image at 1 and 3 mins – FOV mediastinum
--Recon mm section thickness 2

3. Pulmonary Interstitial Lymphography
This is an example of lymphography
Evaluate the images: compare pre and post contrast images
Examine pulmonary interstices, hilum, etc
Positive if 3 mm region of contrast collection
Typical pattern follow distal bronchus, more centrally to hilum, then wall of central bronchus nearing carina, but never collected more proximal than carina

4. Primary Nodal Drainage
Square = primary tumor
Circle = primary drainage
Square = primary tumor
Circle = primary drainage

5. Treatment Planning per 0813
5 fractions, simultaneous integrated boost
RapidArc, >340 d
PTV 50 Gy (primary tumor) coverage
Normalized to 95%
PTV 35 Gy (nodal drainage) coverage (all >, med)
95%, 99.6%
Modulation: MU/cGy ratio (med, max)
2.8, 3.3
Conformality: V50/ PTV volume (med, max)
1.07, 1.10
NTC: Spinal cord V13.5 (med, max)
0.00, 0.20 cc
NTC: Cent airway V18 (med, max)
8.5, 17.2 cc
NTC: Total lung V20 (med, max)
5.5, 7.6%
NTC: Esophagus V27.5 (med, max)
0.0, 9.7 cc
NTC: Heart V32, Gr Vessells V47 (med)
0.10, 0.00