Objective To predict the postoperative pulmonary function using ventilation-perfusion scintigraphy and explore its feasibility in evaluating surgical risk for lung cancer patients with borderline pulmonary functions [forced expiratory volume in 1 s (FEV1) < 2.0 l for pneumonectomy or < 1.5 l for lobectomy]. Methods Twenty lung cancer patients (52-86 years, four women, 16 men) with borderline pulmonary functions were included in this study. Planar ventilation scans with Tc-99m-diethylenetriamine pentaacetic acid aerosol and perfusion scans with Tc-99m-macroaggregated albumin were performed before surgery. Pulmonary function test was performed 1 week before surgery for all patients and 2 months after surgery for 12 patients. The predicted postoperative FEV1 (ppoFEV(1)) values were calculated using Neuhaus equations and compared with FEV1 values after surgery. Results There was no significant statistical difference between the ppoFEV1 values resulting from the ventilation scan (ppoFEV(1)-V) and the ppoFEV(1) values resulting from the perfusion scan (ppoFEV(1)-Q): (1.153 +/- 0.227) l versus (1.204 +/- 0.210) l (n=20, t=0.045, P>0.05). No statistically significant difference existed between the ppoFEV(1)-V values and the postoperative FEV1 values: (1.238 +/- 0.200) l versus (1.28 +/- 0.146) l (n=12, t=0.557, P>0.05), or between the ppoFEV(1)-Q values and the postoperative FEV1 values: (1.302 +/- 0.161) l versus (1.28 +/- 0.146) l (n=12, t=0.288, P>0.05). Both ppoFEV(1)-V values and ppoFEV(1)-Q values fairly correlated with the postoperative FEV1 values (r=0.765, 0.674; t=3.756, 2.885, P<0.01, P<0.01). Conclusion Ventilation-perfusion scans can predict postoperative pulmonary function and help evaluate the risk of surgery for lung cancer patients with borderline pulmonary functions. Nucl Med Commun 33:283-287 (C) 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.