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Contralateral bulla neogenesis associated with postoperative recurrences of primary spontaneous pneumothorax in young patients.

Background
Video-assisted thoracoscopic surgery (VATS) is considered an acceptable treatment for recurrent primary spontaneous pneumothorax (PSP). However, recent reports have described a high postoperative recurrence rate in young patients with PSP. We hypothesized that ineffective VATS may have been performed for these patients (aged <25 years). We evaluated the factors preventing postoperative recurrence in young PSP patients in order to identify patients with effective surgery.


Methods
Between April 2009 and December 2018, we retrospectively evaluated 92 patients aged <25 years who underwent first VATS bullectomy for PSP. Factors such as gender, smoking habit, history of contralateral PSP, family history, body mass index (BMI), and contralateral bulla neogenesis on high-resolution computed tomography were evaluated.


Results
The mean BMI was 18.8±1.8. Contralateral bulla neogenesis was present in 31 patients (33.7%). The median period of observation for postoperative recurrence was 401.5 days. Thirty cases (32.6%) developed postoperative recurrence. Univariate and multivariable analyses showed that a BMI ≥18.0 and no contralateral bulla neogenesis were significant factors preventing postoperative recurrence (P=0.018, hazard ratio: 0.41 and P=0.0046, hazard ratio: 0.25, respectively).


Conclusions
Although the patients aged <25 years have a high rate of postoperative recurrence, the patients with BMI ≥18.0 and no contralateral bulla neogenesis have a significantly lower rate of postoperative recurrence rate.