Purpose: To compare visual detection and computer aided diagnosis (CAD) for detection of non-solid nodules (NSN) and part-solid nodules (PSN), in a lung cancer screening trial. Material and Method: Baseline low-dose computed tomography (LDCT) of 2303 subjects were assessed by 2 independent operators: a) visual detection (VD); b) CAD software (CIRRUS Lung Screening). CAD was run also on first and second incidence round. The rate of agreement was calculated by weighted k test. Sensitivity and negative predictive value (NPV) were calculated according to the cumulative number of subjects with detected nodules (VD and CAD). LDCT features were compared between CAD-only and VD-only detected nodules. Results: Nodules were detected in 215/2303 subjects (dominant nodule: 171/215 NSN and 44/215 PSN), notably 149 were CAD-only detected (113 NSN and 36 PSN), 27 were VD-only detected (25 NSN and 2 PSN), and 39 were CAD and VD detected (33 NSN and 6 PSN). The agreement was fair (weighted k=0.276 95\%CI 0.203-0.350). Sensitivity and NPV for CAD 87.4\% and 98.7\%, and for VD 30.7\% and 93.3\%. Automatic and manual caliper were similar for the assessment of maximum diameter (p=0.111). CAD-only and VD-only detected nodules showed similar nodule diameter (p=0.727) and proportion of PSN (p=0.073). Volume of CAD-only detected nodules was significantly smaller (p=0.019). Among the 27 VD-only detected nodules, 11 NSN were subsequently detected by CAD at the incidence rounds. Conclusion: The detection of NSN and PSN showed only fair agreement between VD and CAD. Combined assessment of LDCT by both VD and CAD is needed to achieve the optimal sensitivity.
Non-solid and Part-solid Nodules: Comparison Between Visual and Computer Aided Detection
M. Silva, G. Capretti, N. Sverzellati, C. Jacobs, F. Ciompi, B. van Ginneken, C. Schaefer-Prokop, M. Prokop, A. Marchiano and U. Pastorino
World Congress of Thoracic Imaging 2017.