Determine the feasibility of liver stereotactic body radiation therapy (SBRT) given in combination with systemic therapy (immune checkpoint inhibitors) in adult patients with metastatic NSCLC with liver metastases.

Inclusion Criteria:

• Adult patients (≥18 years of age)
• Histologically or cytologically confirmed NSCLC with liver metastases
• Eligible for immune checkpoint inhibitors per treating medical oncologist
• Disease must be measurable per RECIST criteria
• ECOG Performance status of 0 - 2
• Adequate organ function per protocol.
• Allowable prior therapy includes adjuvant durvalumab, prior radiotherapy outside the upper abdomen.
• Patients must be willing and able to sign an informed consent form.
• Participants of childbearing potential willing to undergo pregnancy test and use contraception per Appendix.

Exclusion Criteria:

• Liver tumor burden which cannot be targeted with SBRT per treating radiation oncologist
• Presence of uncontrolled intercurrent illness or significant comorbidities precluding participation in a clinical study as determined by investigator
• Diagnosis of underlying parenchymal end stage liver disease (cirrhosis) or biliary disease (primary biliary cirrhosis).
• Other invasive malignancy active within 1 years, excluding in situ cancers
• Presence of psychiatric or substance abuse disorders that would interfere with compliance or safety
• Has a known history of active Bacillus Tuberculosis (TB), Hepatitis B or Hepatitis C infection
• Has received a live (active) vaccine within 30 days of enrollment.
• Active autoimmune disease that has required systemic treatment in the past 1 years aside from hormone replacement therapy (ie. thyroxine, insulin, or physiologic corticosteroid replacement therapy)
• Baseline corticosteroid use (>10 mg prednisone daily or equivalent) at study entry
• Pregnancy or breast feeding