Long-term outcomes of surgical treatment of non-small cell lung cancer with oligometastatic disease involving only the brain in the era of PET/CT.

Background: The prognosis of patients with synchronous oligometastatic non-small cell lung cancer (NSCLC) has been improving owing to advancements in imaging techniques and new treatment approaches such as tyrosine kinase inhibitors. This study aimed to investigate the long-term outcomes, including the clinical course after recurrence, of patients with synchronous oligometastatic NSCLC with only brain metastases, treated with bifocal treatment.

Methods: We retrospectively analyzed 22 patients with clinical T1-4 and N0-1 NSCLC with synchronous brain metastases who were diagnosed by preoperative PET/CT and brain CT or MRI and underwent pulmonary resection for the primary site and surgery or radiation therapy for brain metastases at our institution from 2005 to 2019.

Results: The median follow-up period was 60 months. The 5-year recurrence-free survival rate and overall survival rates after pulmonary resection were 31.8% and 58.7%, respectively. In the univariate analysis, pathological N0 status was significantly associated with better recurrence-free survival, but not overall survival. The median survival after recurrence was 24 months. Aggressive brain treatment at sites of recurrence and the use of TKIs after recurrence have significantly prolonged prognosis.

Conclusions: The long-term outcomes in patients with synchronous oligometastatic NSCLC with brain metastases who underwent bifocal treatment, including pulmonary resection, were favorable. In particular, bifocal treatment may provide a chance for cure in patients without lymph node involvement.