Abstract:

Objective

To analyze the lobar emphysema ratio （LER） for predicting stage Ⅰ-ⅢA nonsmall cell lung cancer （non-small cell lung cancer）.The clinical significance of video-assisted thoracoscopic/thoracic surgery （VATS） after pulmonary resection for persistent air leak （PAL）.

Methods

All of 117 patients with NSCLC treated by VATS pulmonary lobectomy from January 2021 to January 2024 were selected as subjects.PAL （lung leakage time ＞5 days after pneumonectomy） was recorded，19 cases of PAL were observed and 98 cases without PAL were control group.Spearman rank correlation was used to analyze the correlation.Multivariate Logistic regression analysis of PAL risk factors after VATS in NSCLC patients.Subject operating characteristic curves were used to predict PAL risk after VATS in NSCLC patients.

Results

67 cases had gas leakage on the first day after operation，48 cases stopped gas leakage within 5 days，19 cases （16.23%） had gas leakage ＞5 days.There was no death during hospitalization，and no chest tube drainage was performed after discharge.The average length of hospitalization was （6.62±4.01） d and the duration of air leakage was （2.93±3.42） d.The emphysema ratio （ER） of 0.11 （0.02，1.01）% in the observation group was higher than that of the control group by 2.13 （0.85，3.07）%.The upper lobe of the right lung in the observation group was 0.10（0.01，1.38） and the middle lobe of the right lung was 0.18（0.02，1.00）%，lower lobe of right lung 0.04（0.00，0.46）%，upper lobe of left lung 0.09（0.01，1.32）%，lower lobe of left lung 0.06（0.00，0.53）% were higher than those of control group 2.59（0.39，6.16）%，middle lobe of right lung 0.72（0.36，2.00）%，right inferior lobe 1.29（0.13，2.36）%，left superior lobe 1.52（0.74，2.75）%，left inferior lobe 1.75（0.35，3.05）%.Spearman rank correlation analysis showed a strong positive correlation between ER and LER （rho=0.857， P=0.000）.LER predicted that the AUC of PAL after VATS in NSCLC patients was 0.876 （95%CI：0.817-0.922），the optimal cut-off value （0.75），sensitivity and specificity were 85.71% and 80.28%，and positive and negative predictive values were 82.27% and 84.03%，respectively.The AUC of ER predicting PAL after VATS in NSCLC patients was 0.792 （95%CI：0.723-0.850），the optimal cut-off value （0.18） was 92.86%，the specificity was 57.75%，and the PPV and NPV were 70.12% and 88.34%，respectively.LER predicted that PAL occurrence was higher than ER （Z=2.875， P=0.004）.Logistic regression analysis showed that smoking history （OR=5.888， P=0.037），T2-T3 tumor stage （OR=2.696， P=0.036），respiratory complications （OR=2.928， P=0.030） and LER ＞0.75 （OR=15.693， P=0.000） predicted PAL.

Conclusion

ER and LER can predict PAL in patients with stage Ⅰ-ⅢA NSCLC after pulmonary resection of VATS，and the prediction of LER is significant.

Key words: Pulmonary emphysema ratio, Non-small cell lung cancer, Video-assisted thoracoscopic lobectomy, Persistent leak