Thoracic endometriosis-related pneumothorax distinguished from primary spontaneous pneumothorax in females.
OBJECTIVE
Thoracic endometriosis-related pneumothorax (TERP) is a secondary condition specific for females, but in a clinical setting, TERP often is difficult to distinguish from primary spontaneous pneumothorax (PSP) based on a relationship between the dates of pneumothorax and menstruation. The purpose of this study was to clarify the clinical features of TERP compared with PSP.


METHODS
We retrospectively reviewed the clinical and histopathological files of female patients with pneumothorax who underwent video-assisted thoracoscopic surgery in the Pneumothorax Research Center during the 6-year period from January 2005 to December 2010. We analyzed the clinical differences between TERP and PSP.


RESULTS
The study included a total of 393 female patients with spontaneous pneumothorax, of whom 92 (23.4 %) were diagnosed as having TERP and 33.6 % (132/393) as having PSP. We identified four factors (right-sided pneumothorax, history of pelvic endometriosis, age ≥31 years, and no smoking history) that were statistically significant for predicting TERP and assigned 6, 5, 4, and 3 points, respectively, to establish a scoring system with a calculated score from 0 to 18. The cutoff values of a calculated score ≥12 yielded the highest positive predictive value (86 %; 95 % confidence interval (CI) 81.5-90.5 %) for TERP and negative predictive value (95.2 %; 95 % CI 92.3-98 %) for PSP.


CONCLUSIONS
TERP has several distinct clinical features from PSP. Our scoring system consists of only four clinical variables that are easily obtainable and enables us to suspect TERP in female patients with pneumothorax.
Pneumothorax Research Center and Division of Thoracic Surgery, Nissan Tamagawa Hospital, 4-8-1 Seta, Setagaya-ku, Tokyo, 158-0095, Japan.
Takahiro
T
Haga
Hideyuki
H
Kataoka
Hiroki
H
Ebana
Mizuto
M
Otsuji
Kuniaki
K
Seyama
Koichiro
K
Tatsumi
Masatoshi
M
Kurihara
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D003937:Diagnosis, Differential; D004715:Endometriosis / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D006801:Humans; D008875:Middle Aged; D011030:Pneumothorax / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013896:Thoracic Diseases / Q000150:complications / Q000175:diagnosis* / Q000601:surgery; D020775:Thoracic Surgery, Video-Assisted; D055815:Young Adult