Regional Emphysema Score Predicting Overall Survival, Quality of Life, and Pulmonary Function Recovery in Early-Stage Lung Cancer Patients

Abstract

IntroductionPulmonary emphysema is a frequent comorbidity in lung cancer, but its role in tumor prognosis remains obscure. Our aim was to evaluate the impact of the regional emphysema score (RES) on a patient’s overall survival, quality of life (QOL), and recovery of pulmonary function in stage I to II lung cancer. MethodsBetween 1997 and 2009, a total of 1073 patients were identified and divided into two surgical groups—cancer in the emphysematous (group 1 [n = 565]) and nonemphysematous (group 2 [n = 435]) regions—and one nonsurgical group (group 3 [n = 73]). RES was derived from the emphysematous region and categorized as mild (≤5%), moderate (6%–24%), or severe (25%–60%). ResultsIn group 1, patients with a moderate or severe RES experienced slight decreases in postoperative forced expiratory volume in 1 second, but increases in the ratio of forced expiratory volume in 1 second to forced vital capacity compared with those with a mild RES (p < 0.01); however, this correlation was not observed in group 2. Posttreatment QOL was lower in patients with higher RESs in all groups, mainly owing to dyspnea (p < 0.05). Cox regression analysis revealed that patients with a higher RES had significantly poorer survival in both surgical groups, with adjusted hazard ratios of 1.41 and 1.43 for a moderate RES and 1.63 and 2.04 for a severe RES, respectively; however, this association was insignificant in the nonsurgical group (adjusted hazard ratio of 0.99 for a moderate or severe RES). ConclusionsIn surgically treated patients with cancer in the emphysematous region, RES is associated with postoperative changes in lung function. RES is also predictive of posttreatment QOL related to dyspnea in early-stage lung cancer. In both surgical groups, RES is an independent predictor of survival.