Stereotactic Body Radiotherapy (SBRT) Versus Sublobar Resection for High-Risk Patients Non-Small Lung Cancer

The current standard of care for Stage I Non-Small Lung Cancer (NSCLC) is sublobar surgical
resection. Recent trials have suggested that early stage NSCLC might be successfully treated
with SBRT amongst those who are medically inoperable. SBRT is the precise delivery of a high
dose of radiation to control tumors while limiting damage to surrounding normal tissues.
Patients on the SBRT arm will receive 54 Grays (Gy) in 3 fractions. One gray is the
absorption of one joule of energy, in the form of ionizing radiation, per kilogram of matter.
Recent advances with three-dimensional conformal and Intensity Modulated Radiotherapy (IMRT)
techniques can now compensate for lung motion and allow delivery of high-dose, single
fractions to the primary lung tumor for patients with clinical state I NSCLC.

Local control and survival results appear promising. SBRT for early stage lung cancer may
offer a potentially equivalent, non-invasive treatment alternative to surgical resection.
Additionally, SBRT may be associated with fewer complications and better quality of life.
SBRT may be an acceptable or even preferred treatment option in higher-risk patients not able
to tolerate a surgical lobectomy. This clinical dilemma is increasingly faced in our lung
cancer practice at Mayo Clinic, with no comparative effectiveness data to guide treatment
decisions.

Patients will be evaluated by both Thoracic Surgery and Radiation Oncology. Randomization can
occur through either group but a patient must see both in consultation prior to
randomization. For patients meeting enrollment criteria but unwilling to participate in
randomization, observational arms for each of SBRT and sublobar resection will enroll up to
24 patients as part of the 96 patient total.

The patients will receive the following tests as part of their clinical care:

- Computed Tomography (CT)-Positron Emission Tomography (PET) will be used for mediastinal
imaging

- Endobronchial/endoscopic ultrasound (EBUS/EUS)-Fine Needle Aspiration (FNA) or
mediastinoscopy will be used for pathologic assessment of level 2 lymph nodes (N2)
greater than 1 cm in the short axis on CT scan and/or SUV greater than 1.5 fold
background

- Follow-up CT scans at 6 months, 12 months, 18 months, and 24 months for the Surgery and
SBRT groups.

- Follow-up Pulmonary Function Tests at 1 year

Inclusion Criteria

- Patients must have a suspicious lung nodule for clinical stage I NSCLC.

- Pathologic confirmation at the time of surgery is acceptable. Patients randomized to
SBRT require core biopsy for diagnosis prior to treatment.

- Patient must have a mass ≤ 5 cm maximum diameter by CT size estimate that is clinical
stage I (T1N0, T2N0)

- Patient must have a CT scan of the chest and upper abdomen and PET-scan within 60 days
prior to date of registration.

- Patient must have an Eastern Cooperative Oncology Group (ECOG) or Zubrod performance
status 0, 1, or 2.

- Patient must meet at least one major criteria or meet a minimum of two minor criteria
as described below:

Major Criteria:

- Forced expiratory volume in one second (FEV1) ≤ 50% predicted

- Carbon monoxide diffusing capacity (DLCO) ≤ 50% predicted

Minor Criteria:

- Age ≥75

- FEV1 51-60% predicted

- DLCO 51-60% predicted

- Pulmonary hypertension (defined as a pulmonary artery systolic pressure greater than
40 mmHg) as estimated by echocardiography or right heart catheterization

- Poor left ventricular function (defined as an ejection fraction of 40% or less)

- Resting or Exercise Arterial oxygen partial pressure (pO2) ≤ 55 mm Hg or blood oxygen
saturation (SpO2) ≤ 88%

- pCO2 > 45 mm Hg

- Modified Medical Research Council (MMRC) Dyspnea Scale ≥ 3.

Exclusion Criteria

- Patient must not have had previous intra-thoracic radiation therapy.

- No prior malignancy except adequately treated non-melanoma skin cancer, in situ
cervical cancer, localized prostate cancer, stage 0 Chronic lymphocytic leukemia
(CLL), or other cancer disease-free > 3 yrs.