Radiological unilateral pleuroparenchymal fibroelastosis as a notable late complication after lung cancer surgery: incidence and perioperative associated factors

Abstract

Objectives Pleuroparenchymal fibroelastosis (PPFE) is a rare idiopathic interstitial pneumonia characterized by pleural-parenchymal involvements predominantly in the upper lobes. Unilateral upper lung field pulmonary fibrosis (upper-PF) radiologically consistent with PPFE reportedly develops after lung cancer surgery in the operated side and presents many clinical characteristics in common with PPFE. However, the incidence and perioperative associated factors remain unclear. Methods All consecutive patients with lung cancer completely resected from 2008 to 2016 were retrospectively investigated. Pre-/postoperative characteristics were compared between patients with and without unilateral upper-PF. Cumulative incidence curves were estimated by using competing risk analysis. Results Among 587 included patients, 25 patients (4.3%) were diagnosed as unilateral upper-PF. The 3-, 5- and 10-year cumulative incidence of unilateral upper-PF was 2.3%, 3.3% and 5.3%, respectively. In multivariable analysis, male sex, presence of pulmonary apical cap, lobar resection and low % vital capacity (%VC < 80%) were independent perioperative associated factors. The 10-year cumulative incidence was 6.3% in patients treated with lobar resection, 8.0% in male patients, 10.3% in patients with pulmonary apical cap and 14.5% in patients with low %VC. Postoperative pleural effusion at 6 months after surgery was much more common in the patients who later developed unilateral upper-PF (96.0% vs 24.2%). This pleural effusion persisted and was accompanied by pleural thickening and subpleural pulmonary fibrosis thereafter. During the clinical courses of 25 patients with unilateral upper-PF, 18 patients presented symptoms related upper-PF and 6 patients died. Conclusion Unilateral upper-PF is not a rare but under-recognized late complication after lung cancer surgery.