Usefulness of lung perfusion scintigraphy before lung cancer resection in patients with ventilatory obstruction

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.

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.

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.

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.