Prediction of postoperative lung function in lung cancer patients using perfusion scintigraphy

Background: Predicting postoperative lung function is critical in lung cancer patients. Perfusion scintigraphy has been used to estimate postoperative function after lung resection. Purpose: To evaluate the usefulness of the posterior oblique method in relation to other conventional processing methods for predicting postoperative lung function using lung perfusion scintigraphy. Material and Methods: Fifty-five patients with non-small-cell lung cancer who underwent lobectomy were enrolled. Forced expiratory volume in 1 s (FEV1) values were obtained from preoperative and postoperative pulmonary function tests. After performing lung perfusion scintigraphy, predicted FEV1 values were calculated using the segment, conventional, posterior, and posterior oblique methods. Postoperative FEV1 values were compared with predicted FEV1 values. Results: The mean value of the preoperative FEV1 was 2.29 L and that of the postoperative FEV1 was 1.89 L. The mean values of the predicted postoperative FEV1 values for the segment, conventional, posterior, and posterior oblique were 1.83 L, 1.94 L, 1.88 L, and 1.89 L, respectively. Between the observed and predicted FEV1 values, there was a strong correlation without significant difference except for conventional method. Bland–Altman analysis showed that segment and posterior methods underestimated the FEV1, whereas conventional and posterior oblique methods overestimated the FEV1. Conclusion: Predictions with each processing method of lung perfusion scintigraphy showed nearly similar results to the actual postoperative lung function. The posterior oblique method of lung perfusion scintigraphy showed a very small difference to such an extent as to be equal to the observed FEV1, implying that this method may be applied for predicting postoperative lung function in lung cancer patients.