Figure 4.

A 28-year-old male diagnosed with ALK rearrangement lung adenocarcinoma. (A) DESCT 70 keV image showing a solid nodule in the inferior lobe of the left lung, with a CT value at 70 keV of 33.93 HU. (B) Water-based material-decomposition image showing a WC of the nodule of 1,019.04 µg/cm³. (C) The graph shows the spectral Hounsfield unit curve of the nodule with a λHU slope of 0.7. (D) Immunohistochemistry showing ALK rearrangement. (E) ALK rearrangement prediction according to various significant factors and their combination (with AUC =0.748). WC, water concentration; DESCT, dual-energy spectral computed tomography; λHU slope, spectral Hounsfield unit curve; ROC, receiver operating characteristic; AUC, area under curve.