Stage 1 non-small cell lung cancer (NSCLC) carries up to 30% chance of relapse in 5 years. Surgery is standard-of-care for this population. For patients who are not candidate for surgery, stereotactic ablative radiotherapy (SABR) is standard, with good local control but locoregional and distant failure. The use of preoperative SABR leads to a pathological complete response rate (pCR) of 60%. Anti-PD-1 has the ability to provoke a pCR in around 20% of patients as a single agent. Moreover, it has synergic activity with radiotherapy.

This a phase 2 study that aims to determine the pathological complete response of the combination of stereotactic ablative radiotherapy plus nivolumab as neoadjuvant treatment in early-stage non-small cell lung cancer. The patients will receive standard SABR, given either as 3, 5 or 8 fractions (depending on tumor size and location) + nivolumab at a dose of 360 mg every 21 days for 3 doses. The patient will undergo surgery 10 weeks after the last radiotherapy dose. We will measure translational biomarkers associated with either pCR or resistance to therapy.