Assessment of lung cancer development in idiopathic pulmonary fibrosis patients using quantitative high-resolution computed tomography: a retrospective analysis

Purpose: The purpose of this study was to investigate histogram-based quantitative high-resolution computed tomography (HRCT) indexes in the assessment of lung cancer (LC) development in idiopathic pulmonary fibrosis (IPF) patients. Materials and methods: From IPF databases of 2 national respiratory centers, we retrospectively studied patients with and without LC development-respectively, divided into Group A (n=16) and Group B (n=33). The extent of fibrotic disease was quantified on baseline and follow-up HRCT examinations using kurtosis, skewness, percentage of high attenuation area (HAA%), and percentage of fibrotic area (FA%). These indexes were compared between the 2 groups using the Mann-Whitney U test. In the prediction of LC development, receiver operating characteristic analysis was performed to assess threshold values of HRCT indexes. Results: At baseline, no difference was reported among groups for kurtosis, skewness, HAA%, and FA%, with P-values of 0.0881, 0.0606, 0.0578, and 0.0606, respectively. On follow-up, significant differences were reported, with P-values of 0.0174 for kurtosis, 0.0313 for skewness, 0.0297 for HAA%, and 0.0407 for FA%.On baseline HRCT, in the prediction of LC development, receiver operating characteristic analysis reported sensibility and specificity of 87.5% and 45.45% for kurtosis, 68.75% and 63.64% for skewness, 81.25% and 54.55% for FA%, and 75% and 60.61% for HAA%. Conclusions: LC development is associated with progression of fibrosis; at baseline, FA% and HAA% reported more convenient sensitivity/specificity ratios in the prediction of LC development.