Post Surgical

Patients with stage III non-small-cell lung cancer (NSCLC) who receive neoadjuvant chemoimmunotherapy may achieve good response in the primary tumor but still have residual nodal disease after surgery (ypTanyN⁺M0), which is associated with poor prognosis in retrospective analyses from our center. In prior trials such as LungART and PORT-C, postoperative radiotherapy (PORT) did not improve disease-free survival in completely resected stage IIIA-N2 NSCLC after adjuvant chemotherapy, suggesting that PORT should not be used indiscriminately. However, recent preclinical and translational data indicate that radiotherapy can enhance antitumor immunity, remodel the tumor microenvironment, and synergize with immune checkpoint inhibitors via immunogenic cell death, improved T-cell trafficking, and tertiary lymphoid structure formation. This single-center randomized phase II study will evaluate whether adding postoperative involved-field nodal radiotherapy to standard PD-1 maintenance therapy can improve disease-free survival compared with PD-1 maintenance alone in patients with ypTanyN⁺M0 NSCLC after neoadjuvant chemoimmunotherapy and R0 resection.