Long-Term Survival Achieved by Combined Surgical Resection and Immunotherapy for Recurrent Adrenal Oligometastasis of Lung Adenocarcinoma: A Case Study.

A 73-year-old woman with epidermal growth factor receptor (EGFR) L858R-mutant lung adenocarcinoma (cT4N1M1a stage IV, programmed death-ligand 1 (PD-L1) high expression (60%)) received osimertinib as first-line therapy, but disease progression was observed after two months. She subsequently received second-line therapy with carboplatin, paclitaxel, and atezolizumab, followed by maintenance atezolizumab. During maintenance therapy, solitary metastasis developed in the left adrenal gland, while all other lesions remained well controlled. The condition was diagnosed as oligoprogression, and laparoscopic left adrenalectomy was performed. Histopathological examination confirmed adrenal metastasis from lung cancer. Atezolizumab was resumed 42 days after surgery, and the patient has remained recurrence-free for more than four years, achieving long-term survival. With the widespread use of immune checkpoint inhibitors (ICIs), the prognosis of advanced non-small cell lung cancer has improved. However, the optimal treatment strategy for patients who develop localized progression (oligoprogression) during systemic therapy has not been established. This case demonstrates long-term survival achieved by combining surgical resection with resumption of ICI therapy for solitary adrenal oligoprogression during ICI maintenance therapy. The findings suggest that local treatment for limited progressive lesions during ICI therapy may be a useful therapeutic strategy.