An Exceptional Responder to Nivolumab in MetastaticNon-Small-Cell Lung Cancer: A Case Report and LiteratureReview of Long-Term Survivors

Exceptional responders to immune checkpoint inhibitors in metastatic non-small-cell lung cancer (NSCLC) are rare.Furthermore, the optimal duration of immunotherapy in patients who achieve complete remission and the benefit of rechallengeafter recurrence remain unknown. Studying the clinical course of exceptional responders can help identify potential predictors ofresponse to immunotherapy and furtherfine-tune our management algorithms in the absence of standard of care in challengingscenarios.Case Presentation. We highlight the case of a 73-year-old Vietnam War Veteran with active tobacco dependence whoachieved complete response with nivolumab for metastatic NSCLC after four prior lines of chemotherapy. Nivolumab wasdiscontinued after 10 cycles due to immune-mediated hepatitis that resolved with steroids. He remained in complete remissionfor 14 months while offtherapy. Then, his tumor recurred twice locally in the mediastinum and he again achieved complete anddurable responses after each recurrence with radiotherapy. Due to recurrence in both lungs one year later, he was rechallengedwith nivolumab and achieved partial response after two months of therapy. He continues to do wellfive and a half years sincehis initial diagnosis of de novo metastatic NSCLC.Conclusion. Optimal management of exceptional responders to immunecheckpoint inhibitors in metastatic NSCLC is largely unknown. Our case report adds to the limited data supporting the use oflocalized therapy for oligometastatic recurrences and rechallenge with immunotherapy for widespread disease in achievingdisease control and long-term survival.