Molecular analysis of the mutation status for EGFR and KRAS are now routine in the management of non-small cell lung cancer. Radiogenomics, the linking of medical images with the genomic properties of human tumors, provides exciting opportunities for non-invasive diagnostics and prognostics. We investigated whether EGFR and KRAS mutation status can be predicted using imaging data. To accomplish this, we studied 186 cases of NSCLC with preoperative thin-slice CT scans. A thoracic radiologist annotated 89 semantic image features of each patient’s tumor. Next, we built a decision tree to predict the presence of EGFR and KRAS mutations. We found a statistically significant model for predicting EGFR but not for KRAS mutations. The test set area under the ROC curve for predicting EGFR mutation status was 0.89. The final decision tree used four variables: emphysema, airway abnormality, the percentage of ground glass component and the type of tumor margin. The presence of either of the first two features predicts a wild type status for EGFR while the presence of any ground glass component indicates EGFR mutations. These results show the potential of quantitative imaging to predict molecular properties in a non-invasive manner, as CT imaging is more readily available than biopsies.

Accurate clinical or pretreatment stage classification of lung cancer leads to optimal treatment outcomes and improved prognostication. Such classification requires an accurate assessment of the clinical extent of regional lymph node metastasis. Consistent and reproducible regional lymph node designations facilitate reliable assessment of the clinical extent of regional lymph node metastasis. Regional lymph node maps, such as the Naruke lymph node map and the Mountain-Dresler modification of the American Thoracic Society lymph node map, were proposed for this purpose in the past. The most recent regional lymph node map to be published is the International Association for the Study of Lung Cancer (IASLC) lymph node map. The IASLC lymph node map supersedes all previous maps and should be used in tandem with the current seventh edition of the tumor, node, metastasis stage classification for lung cancer.

Chronic thromboembolic pulmonary hypertension (CTEPH) is one of the potentially curable causes of pulmonary hypertension and is definitively treated with pulmonary thromboendartectomy. CTEPH can be overlooked, as its symptoms are nonspecific and can be mimicked by a wide range of diseases that can cause pulmonary hypertension. Early diagnosis of CTEPH and prompt evaluation for surgical candidacy are paramount factors in determining future outcomes. Imaging plays a central role in the diagnosis of CTEPH and patient selection for pulmonary thromboendartectomy and balloon pulmonary angioplasty. Currently, various imaging tools are used in concert, with techniques such as computed tomography (CT) and conventional pulmonary angiography providing detailed structural information, tests such as ventilation-perfusion (V/Q) scanning providing functional data, and magnetic resonance imaging providing a combination of morphologic and functional information. Emerging techniques such as dual-energy CT and single photon emission computed tomography-CT V/Q scanning promise to provide both anatomic and functional information in a single test and may change the way we image these patients in the near future. In this review, we discuss the roles of various imaging techniques and discuss their merits, limitations, and relative strengths in depicting the structural and functional changes of CTEPH. We also explore newer imaging techniques and the potential value they may offer.

Purpose To compare the diagnostic yield and complication rates of electromagnetic navigational bronchoscopic (ENB)-guided and computed tomography (CT)-guided percutaneous tissue sampling of lung nodules. Materials and Methods Retrospectively identified were 149 patients sampled percutaneously with CT guidance and 146 patients who underwent ENB with transbronchial biopsy of a lung lesion between 2013 and 2015. Clinical data, incidence of complications, and nodule pathologic analyses were assessed through electronic medical record review. Lung nodule characteristics were reviewed through direct image analysis. Molecular marker studies and pathologic analyses from surgical excision were reviewed when available. Multiple-variable logistic regression models were built to compare the diagnostic yield and complication rates for each method and for different patient and disease characteristics. Results CT-guided sampling was more likely to be diagnostic than ENB-guided biopsy (86.0% [129 of 150] vs 66.0% [99 of 150], respectively), and this difference remained significant even after adjustments were made for patient and nodule characteristics (P < .001). Age, American Society of Anesthesiologists class, emphysema grade, nodule size, and distance from pleura were not significant predictors of increased diagnostic yield. Intraprocedural time for physicians was significantly lower with CT-guided sampling (P < .001). Similar yield for molecular analyses was noted with the two approaches (ENB-guided sampling, 88.9% [32 of 36]; CT-guided sampling, 82.0% [41 of 50]). The two groups had similar rates of major complications (symptomatic hemorrhage, P > .999; pneumothorax requiring chest tube and/or admission, P = .417). Conclusion CT-guided transthoracic biopsy provided higher diagnostic yield in the assessment of peripheral pulmonary nodules than navigational bronchoscopy with a similar rate of clinically relevant complications. RSNA, 2017 Online supplemental material is available for this article.