Clinical outcomes of lung metastases after gastrectomy for gastric cancer.

Abstract

Lung metastases from gastric cancer are rare, and their clinical behavior remains poorly characterized. Improved understanding of their clinical characteristics may help optimize treatment strategies. This study aimed to assess the disease course and outcomes of lung metastases after gastrectomy for gastric cancer. Patients who underwent gastrectomy for gastric cancer and were diagnosed with lung metastases between January 2000 and December 2023 were retrospectively reviewed. Clinical and radiologic data were analyzed to assess disease course and prognostic factors. Among 22,927 patients who underwent gastrectomy, 110 (0.5%) developed lung metastases. The median interval from gastrectomy to diagnosis was 18 months (interquartile range, 10-38). Most patients had bilateral (64.5%) or multiple (≥4) lung lesions (74.5%), and the most common radiologic pattern of metastatic spread was hematogenous (68.2%). Isolated lung metastases as initial recurrence occurred in 28.2% of patients. The most frequent concomitant metastatic site was distant lymph nodes (48.2%). The median overall survival after diagnosis of lung metastasis was 10 months (interquartile range, 5-32), and the 5-year overall survival rate was 14.5%. Longer survival was observed in patients with unilateral involvement (P = .007), 3 or fewer lesions (P = .001), hematogenous spread (P < .001), or isolated lung metastases (P = .039). In multivariable analysis, metastatic spread pattern (P < .001), diagnosis era (P = .001), and pulmonary metastasectomy (P = .008) were associated with overall survival. Despite the dismal prognosis, selected patients with limited metastatic burden demonstrated favorable survival. Characterizing metastatic burden at recurrence may help identify highly selected patients who could be considered for local treatment.