Usefulness of Lung Perfusion Scintigraphy Before Lung Cancer Resection in Patients with Ventilatory Obstruction

Background: The study was conducted to evaluate the efficacy of preoperative lung perfusion scintigraphy performed by planar acquisition and single-photon emission computed tomography (SPECT) in predicting postoperative pulmonary function of patients with resectable lung cancer and obstructive ventilatory defect. Methods: The study enrolled 39 patients (mean age, 67 ± 2.1 years). All patients underwent preoperative and postoperative pulmonary function tests. Cut-off values for postoperative forced expiratory volume in 1 second (FEV₁) were 65% of the predicted value for pneumonectomy and 45% for lobectomy. A semiquantitative analysis of planar and SPECT lung perfusion scintigraphy images was performed preoperatively to estimate postoperative predicted FEV₁ (FEV₁ppo). Relationships between FEV₁ppo and measured postoperative FEV₁ were tested by the Pearson correlation and Bland Altman agreement tests. Results: Twenty-eight lobectomies and 11 pneumonectomies were performed. The FEV₁ppo estimated by mean planar lung scintigraphy was 1.85 ± 0.38 L, with a Pearson correlation coefficient to the measured FEV₁ of 0.8632 (p <0.001). The mean FEV₁ppo estimated by SPECT was 1.78 ± 0.31 L, with a Pearson coefficient to the measured FEV₁ of 0.8527 (p <0.001). Both values showed a more significant correlation with postoperative measured FEV₁ after lobectomy (p <0.001) than after pneumonectomy (p = 0.045). The Bland Altman test confirmed satisfactory agreement of FEV₁ppo estimated by both planar lung scintigraphy and SPECT with FEV₁ measured by spirometry. Conclusions: Both planar lung scintigraphy and SPECT can accurately predict postoperative FEV₁ and can therefore be considered reliable tools in establishing operability of patients with lung cancer and ventilatory obstruction.