Multi-Institutional Review of Spontaneous Pneumothorax (SP) over an 11 Year Period
Deborah Belchis, Christopher Gocke, Kris Shekitka. Johns Hopkins University, Baltimore, MD; St. Agnes Hospital, Baltimore, MD
Background: SP is a well-recognized complication of a variety of systemic and local disorders. In each of these conditions SP affects only a subset of the patients, raising the question of whether or not there are biologic differences in the affected subsets. This multi-institutional study attempted to identify unique clinicopathologic features in a large cohort with SP.
Design: The pathology files of 3 institutions over an 11 year period were searched for cases of SP. Charts and radiographic reports were reviewed. Slides were evaluated for a variety of histologic features.
Results: A total of 110 cases were retrieved: 26 women, 83 men and 1 unknown. The average ages by institution were 59, 46, and 37. 66 cases had identifiable disorders: 40 COPD, 12 cancer, 5 UIP (2 of which also had cancer), 1 pneumoconiosis, 3 infection (2 HIV with pneumocystis, 1 TB), 2 sarcoid, 1 SLE, 1 thrombotic vasculopathy, and 1 LCH. 1 was a presumed case of IPPFE, 1 Marfan's syndrome. 7 patients had a family history of lung disease: 2 with family history of pneumothorax, 2 with family history of lung cancer, and 1 each with family histories of emphysema, COPD and not further classified. A subset of patients had cystic lung disease not otherwise classified and 1 patient had unusual cellular areas suggestive of LAM but negative for HMB-45. 69 were smokers, 14 were non-smokers and 27 unknown. 44 cases had no obvious underlying etiology. In this group, 35 were men, 10 women. The average age was 30 (men) and 39 (women). Morphologic findings were similar to those identified by others including eosinophilic pleuritis, pleural fibrosis, blebs, small airways disease, intraalveolar macrophages and chronic inflammation. In addition, 3 unique clinicopathologic subsets were identified including a novel entity we recently described, pneumothorax-associated fibroblastic lesion (PAFL). Another subset of patients had extensive intraalveolar infiltrate creating a DIP-like appearance. A third subset had cellular alveolar septae.
Conclusions: Approximately 59% of SP have underlying associated disorders. Some of these disorders are not typically associated with SP. The mean age differed across institutions, possibly representing variations in clinical approach to SP or patient response. Several distinct morphologic lesions were identified: PAFL, a subset with cellular septae, and a third with numerous intraalveolar macrophages (DIP-like appearance).
Tuesday, March 5, 2013 1:00 PM
Poster Session IV # 292, Tuesday Afternoon