PURPOSE:The chest radiograph (CXR) is used for evaluation of asbestos-related disease (ARD). Computed tomography (CT) is more accurate for asbestosis and pleural thickening (PT) in established disease. A principal role of radiographic imaging is screening, for which low dose (LD) CT is suited. There are no comparisons of CXR with LDCT for ARD. We assessed: (1) whether LDCT confirms interstitial fibrosis (IF) and PT and (2) detects cases not recognized on CXR.
METHODS:6220 nuclear workers had CXR for ARD and LDCT for lung cancer. Each CXR was read by a “B” reader. Each LDCT was read by a thoracic radiologist specifying IF and PT. The positive and negative predictive value (PPV and NPV) of CXR were calculated.
RESULTS:Of 96 subjects with IF by CXR, 24 had IF by LDCT (PPV 25%). Of 319 subjects with PT by CXR, 127 had PT detected by LDCT (PPV 40%). 130 additional subjects (2% of workforce) had IF and 188 (4%) had PT detected by CT alone.
CONCLUSION:LDCT confirmed IF in 25%. Most cases read by CXR (87/96) were low profusion (scores 1/0–1/2). CXR score correlated with CT. CT revealed IF in 2% with negative CXR, 10% with equivocal CXR (0/1, 1/0), 29% with less severe IF (1/1, 1/2) and 77% with severe IF (≥ 2/1). The majority of cases nowadays are equivocal or less severe in which the CXR is often not confirmed. Additionally, CT detected IF in 111 cases not detected by CXR (0/0). CT confirmed PT in 40% of cases read by CXR and detected PT in 188 cases (4%) not read on CXR.
CLINICAL IMPLICATIONS:Most cases of asbestosis are low profusion, in which the CXR was often not confirmed by LDCT. 60% of CXR readings of PT were not confirmed by LDCT. The CXR demonstrated a high NPV for PT (96%) and especially for IF (98%). Nevertheless, the majority of cases were detected by CT alone.
DISCLOSURE:Albert Miller, No Financial Disclosure Information; No Product/Research Disclosure Information