Fig. 1

PRISMA flow diagram for studies with patients with pulmonary metastases Includes studies with NSCLC and patients with pulmonary metastases. See Sect. 9.0 of the Online Supplement for a list of included studies with patients with pulmonary metastases. b Two studies with duplicate patients combined for the quantitative synthesis. Abbreviations: NSCLC = non-small cell lung cancer; PRISMA = Preferred Reporting Items for Systematic Reviews