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Influence of lung resection volume on risk of primary spontaneous pneumothorax recurrence.

Background
Thoracoscopic stapled bullectomy is a popular procedure for the treatment of primary spontaneous pneumothorax (PSP) that has a relatively high postoperative recurrence rate. One reason for PSP recurrence is the formation of a new bulla around the staple line. We hypothesized that different resected specimen volumes might cause differences in staple line tension. In this study, we analyzed the relationship between postoperative pneumothorax recurrence and resected lung volume.


Methods
Between April, 2009 and December 2013, 360 cases which underwent video-assisted thoracoscopic surgery (VATS) for PSP were selected. Recurrence after VATS was examined by electronic medical records and telephone survey. Resected volume and vertical area of specimen were calculated with the size of pathologic specimen.


Results
A mean follow up period was 44.5±24.4 months and recurrence rate was 11.1% (40/360). Large volume of resected specimen (≥16 cm3) (P=0.027 by the log-rank test) and larger vertical area of resected specimen (≥2.0 cm2) (P=0.003 by the log-rank test) showed significantly high recurrence rate. Cox regression analysis demonstrated that age [hazard ratio (HR), 0.083, P=0.006], vertical section area of resected specimen (HR, 1.239, P=0.020) and volume of resected pathology specimen (HR, 1.039, P=0.009) were independent risk factors of recurrence.


Conclusions
Bulky resection during VATS for PSP increases the risk of recurrence. Large volume and vertical area of resected specimen are associated with greater tension in stapling line. Avoidance of wide resection and the firing of stapler after full collapse of lung are recommended for reducing the pneumothorax recurrence after VATS.