Background It is important to distinguish the classification of lung adenocarcinoma. A radiomics model was developed to predict tumor invasiveness using quantitative and qualitative features of pulmonary ground-glass nodules (GGNs) on chest CT. Materials and Methods A total of 599 GGNs [including 202 preinvasive lesions and 397 minimally invasive and invasive pulmonary adenocarcinomas (IPAs)] were evaluated using univariate, multivariate, and logistic regression analyses to construct a radiomics model that predicted invasiveness of GGNs. In primary cohort (comprised of patients scanned from August 2012 to July 2016), preinvasive lesions were distinguished from IPAs based on pure or mixed density (PM), lesion shape, lobulated border, and pleural retraction and 35 other quantitative parameters (P <0.05) using univariate analysis. Multivariate analysis showed that PM, lobulated border, pleural retraction, age, and fractal dimension (FD) were significantly different between preinvasive lesions and IPAs. After logistic regression analysis, PM and FD were used to develop a prediction nomogram. The validation cohort was comprised of patients scanned after Jan 2016. ResultsThe model showed good discrimination between preinvasive lesions and IPAs with an area under curve (AUC) of 0.76 [95% CI: 0.71 to 0.80] in ROC curve for the primary cohort. The nomogram also demonstrated good discrimination in the validation cohort with an AUC of 0.79 [95% CI: 0.71 to 0.88]. Conclusions For GGNs, PM, lobulated border, pleural retraction, age, and FD were features discriminating preinvasive lesions from IPAs. The radiomics model based upon PM and FD may predict the invasiveness of pulmonary adenocarcinomas appearing as GGNs.

Background: Pancreatic hamartoma is an extremely rare benign disease, and previous reports have provided little detail regarding its appearance in imaging. As a result, we report the imaging findings for two cases of pancreatic hamartoma. Case presentation: One 57-year-old female patient and one 69-year-old male patient presented with pancreatic lesions incidentally detected by US; CT and MRI revealed a 2.9-cm cystic and solid lesion and a 1.4-cm solid lesion, respectively. US showed a hypoechoic well-defined mass in the pancreatic head. The plain CT indicated that the internal density was uneven, and the lesions showed obvious progressive enhancement. The MRI-T2WI showed isoto high-intensity, the DWI showed iso-intensity, and the masses also all showed obvious progressive enhancement. Histopathological studies confirmed the diagnosis of pancreatic hamartoma. Conclusion: Pancreatic hamartoma is an extremely rare tumour with benign features, such as no dilatation of the MPD and well-defined, slight hyperintensity or iso-intensity on T2WI and iso-intensity on DWI, with obvious progressive enhancement. Therefore, detailed review of multiple imaging modalities may help in diagnosis of PH and prevent unnecessary surgery for patients with this diagnosis.