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Introduction: The abscopal effect is an elusive phenomenon first described by Mole in 1953 as tumor regression observed at sites distant to an irradiated area. Anti-PDL1 monoclonal antibodies (such as nivolumab) were recently approved as first and second-line treatment for advanced-stage NSCLC, but overall response rates remain low for these patients. Herein, we report two cases of stage IV lung adenocarcinoma that achieved complete response after the addition of radiation therapy to an existing anti-PD-1 regimen. Methods: Retrospective chart review of two patients was conducted, followed by systematic literature review using PubMed for abscopal effect observed in lung adenocarcinoma. Results: Two patients with widely metastastic lung adenocarcinoma and progression on multimodal therapy experienced complete resolution of radiographic disease after palliative radiotherapy administered in combination with maintenance anti-PD-1 therapy. Conclusion: Few studies describe the abscopal phenomenon in lung cancer. Adjunct radiotherapy may boost response rates in advanced-stage NSCLC managed with checkpoint inhibition via the abscopal effect. Investigative efforts are necessary to examine combined immunoradiotherapy in metastatic NSCLC.