After completion of Phase I, it was decided not to initiate Phase II of the study.

The purpose of this study is to test whether 5 fraction stereotactic ablative body radiation (SABR) is safe and improves local control for early state squamous cell carcinoma of the lung. While three fraction SABR is effective for the treatment of early stage non small cell lung carcinoma (NSCLC) of all histologies, it is not safe for many patients. While four and five fraction SABR is safe, recently published data and our institutional data suggests that local control for early stage squamous cell carcinoma of the lung using the current four or five fraction SABR is suboptimal.

1. Primary Objectives During Phase I study - Determine the safety and maximum tolerated radiation dose for five fraction SABR for squamous cell cancer of the lung.

   During Phase II study - Determine 2 year local control of dose escalated five fraction SABR vs. institutional historical control standard dose SABR in squamous cell cancer of the lung.

2. Phase II Secondary Objectives

   • Determine overall survival, progression free survival and patterns of failure after SABR.
   • Determine tolerability of dose escalated SABR.

Inclusion Criteria

1. Age ≥ 18 at time of consent.
2. Ability to provide written informed consent and HIPAA authorization.
3. Pathological diagnosis of squamous cell carcinoma of the lung.
4. Staging PET/CT (invasive mediastinal staging strongly encouraged but not required).
5. Tumors < 7cm
6. Any location eligible for SBRT (including, but not limited to, peripheral, chest wall abutting and central tumors)
7. N0 M0 disease
8. Plan to undergo four or five fraction SABR
9. Baseline PFTs available within 6 months of treatment start or will be obtained prior to treatment start (no finding will exclude patient from enrollment in trial)

Exclusion Criteria

1. Previous radiation therapy to the lung per investigator discretion.
2. Inability to comply with treatment per investigator discretion.
3. Inability to follow standard of care follow up recommendations per investigator discretion.
4. KPS<40