Meta-analysis of survival after pulmonary resection for isolated metachronous pancreatic cancer metastasis: A promising, albeit infrequent, approach

Objectives To evaluate survival outcomes of pulmonary resection for isolated metachronous pancreatic cancer metastasis. Methods A systematic search of electronic data sources and reference lists were conducted. Proportion meta-analysis model was constructed to quantify 1- to 5-year survival after pulmonary resection for isolated metachronous pancreatic cancer metastasis. Random-effects modelling was applied to calculate pooled outcome data. Results Twenty-four retrospective studies were included reporting a total of 168 patients who underwent pulmonary resection for isolated pancreatic cancer metastasis. The nature of the index pancreatic surgery included 65% pancreaticoduodenectomies, 17.5% distal pancreatectomies, 0.5% total pancreatectomy, and 17% unspecified. Adjuvant chemotherapy was given to 88% of the patients. The median disease-free interval was 35 (8-96) months. The type of pulmonary resection included 54% wedge resections, 26% lobectomies, 4% segmentectomies, 1% pneumonectomies, and 15% unspecified. Pulmonary resection was associated with 1-year survival of 91.1% (95% CI 86.6%-95.5%), 2-year survival of 77.5% (95% CI 68.9%-86.0%), 3-year survival of 65.0% (95% CI 50.7%-79.3%), 4-year survival of 52.0% (95% CI 37.2%-66.9%), and 5-year survival of 37.0% (95% CI 25.0%-49.1%). Conclusions Pulmonary resection for isolated pancreatic cancer metastasis is associated with acceptable overall patient survival. We recommend selective pulmonary resection for isolated pulmonary metastasis from pancreatic cancer. Our findings may encourage conduction of better-quality studies in this context to help establishment of definitive treatment strategies.