Lessons from surgery after neoadjuvant chemoimmunotherapy for bulky, invasive N2 lung cancer: a case report.

BACKGROUND: Neoadjuvant nivolumab plus chemotherapy increases pathologic complete response rates in resectable non-small cell lung cancer, but the operative safety of this approach in bulky, invasive N2 disease with suspected great-vessel involvement remains uncertain. CASE PRESENTATION: A 64-year-old woman had left upper lobe adenocarcinoma with bulky single-station N2a disease and suspected aortic arch invasion. After three cycles of nivolumab plus carboplatin-paclitaxel, imaging showed only limited nodal shrinkage. At lobectomy, the subaortic lymph node was broadly adherent to the arch and surrounding structures, causing hemorrhage that required cardiopulmonary bypass and arch resection. Pathology showed pathologic complete response, but lymphocyte-predominant inflammation and fibrosis extended to the aortic adventitia. CONCLUSIONS: Radiographic response and pathologic complete response after chemoimmunotherapy do not necessarily indicate safe technical resectability in bulky, invasive N2 lung cancer. Multidisciplinary surgical planning should preserve caution when great-vessel invasion is suspected.