Palmi Shah

Development and validation of a plasma biomarker panel for discerning clinical significance of indeterminate pulmonary nodules.

Introduction: The recent findings of the National Lung Screening Trial showed 24.2% of individuals at high risk for lung cancer having one or more indeterminate nodules detected by low-dose computed tomography–based screening, 96.4% of which were eventually confirmed as false positives. These positive scans necessitate additional diagnostic procedures to establish a definitive diagnosis that adds cost and risk to the paradigm. A plasma test able to assign benign versus malignant pathology in high-risk patients would be an invaluable tool to complement low-dose computed tomography–based screening and promote its rapid implementation. Methods: We evaluated 17 biomarkers, previously shown to have value in detecting lung cancer, against a discovery cohort, comprising benign (n = 67) cases and lung cancer (n = 69) cases. A Random Forest method based analysis was used to identify the optimal biomarker panel for assigning disease status, which was then validated against a cohort from the Mayo Clinic, comprising patients with benign (n = 61) or malignant (n = 20) indeterminate lung nodules. Results: Our discovery efforts produced a seven-analyte plasma biomarker panel consisting of interleukin 6 (IL-6), IL-10, IL-1ra, sIL-2R&agr;, stromal cell-derived factor-1&agr;+&bgr;, tumor necrosis factor &agr;, and macrophage inflammatory protein 1 &agr;. The sensitivity and specificity of our panel in our validation cohort is 95.0% and 23.3%, respectively. The validated negative predictive value of our panel was 93.8%. Conclusion: We developed a seven-analyte plasma biomarker panel able to identify benign nodules, otherwise deemed indeterminate, with a high degree of accuracy. This panel may have clinical utility in risk-stratifying screen-detected lung nodules, decrease unnecessary follow-up imaging or invasive procedures, and potentially avoid unnecessary morbidity, mortality, and health care costs.

CT screening for lung cancer: Value of expert review of initial baseline screenings

OBJECTIVE. Appropriate radiologic interpretation of screening CT can minimize unnecessary workup and intervention. This is particularly challenging in the baseline round. We report on the quality assurance process we developed for the International Early Lung Cancer Action Program. MATERIALS AND METHODS. After initial training at the coordinating center, radiologists at 10 participating institutions and at the center independently interpreted the first 100 baseline screenings. The radiologist at the institutions had access to the center interpretations before issuing the final reports. After the first 100 screenings, the interpretations were jointly discussed. This report summarizes the results of the initial 100 dual interpretations at the 10 institutions. RESULTS. The final institution interpretations agreed with the center in 895 of the 1000 interpretations. Compared with the center, the frequency of positive results was higher at eight of the 10 institutions. The most frequent reason of discrepant interpretations was not following the protocol (n = 55) and the least frequent was not identifying a nodule (n = 3). CONCLUSION. The quality assurance process helped focus educational programs and provided an excellent vehicle for review of the protocol with participating physicians. It also suggests that the rate of positive results can be reduced by such measures.

Stereotactic Body Radiation Therapy for Early-Stage Non–Small Cell Lung Cancer: A Primer for Radiologists

The past 2 decades have seen a rapid growth in use of stereotactic body radiation therapy (SBRT) for the management of non-small cell lung cancer (NSCLC). Not only is SBRT the reference standard for treatment of early-stage node-negative NSCLC in medically inoperable patients, it is also currently challenging the role of surgery for early-stage operable disease. SBRT is also used to treat recurrent disease and has a role in the management of multiple synchronous lung cancers. Imaging changes after SBRT differ from the changes after conventional radiation therapy in many ways, the knowledge of which is pertinent for accurate image interpretation. Posttreatment response assessment and detection of recurrent disease are heavily reliant on radiologic assessment, and often the decision to treat recurrent disease is based on the imaging findings themselves. This article provides a comprehensive review of the concepts of SBRT and the current indications for its use in the treatment of early-stage NSCLC, as well as a discussion of the CT findings seen after SBRT compared with the changes after conventional radiation therapy. Radiologic findings that are suggestive of recurrent disease and the imaging pitfalls are also highlighted. Finally, the rare complications after SBRT are described. SBRT is a major component of the changing treatment paradigms for early- and late-stage NSCLC. The imaging findings after SBRT often determine the next steps in a patients clinical management. Therefore, radiologists must be familiar with the uses of this therapy and its radiologic appearance to be able to effectively contribute to the care of patients with NSCLC. ©RSNA, 2018.

Evaluation of an interactive science publishing tool: toward enabling three-dimensional analysis of medical images.

RATIONALE AND OBJECTIVES Higher resolution medical imaging platforms are rapidly emerging, but there is a challenge in applying these tools in a clinically meaningful way. The purpose of the current study was to evaluate a novel three-dimensional (3D) software imaging environment, known as interactive science publishing (ISP), in appraising 3D computed tomography images and to compare this approach with traditional planar (2D) imaging in a series of lung cancer cases. MATERIALS AND METHODS Twenty-four physician volunteers at different levels of training across multiple specialties were recruited to evaluate eight lung cancer-related clinical vignettes. The volunteers were asked to compare the performance of traditional 2D versus the ISP 3D imaging in assessing different visualization environments for diagnostic and measurement processes and to further evaluate the ISP tool in terms of general satisfaction, usability, and probable applicability. RESULTS Volunteers were satisfied with both imaging methods; however, the 3D environment had significantly higher ratings. Measurement performance was comparable using both traditional 2D and 3D image evaluation. Physicians not trained in 2D measurement approaches versus those with such training demonstrated better performance with ISP and preferred working in the ISP environment. CONCLUSIONS Recent postgraduates with only modest self-administered training performed equally well on 3D and 2D cases. This suggests that the 3D environment has no reduction in accuracy over the conventional 2D approach, while providing the advantage of a digital environment for cross-disciplinary interaction for shared problem solving. Exploration of more effective, efficient, self-directed training could potentially result in further improvement in image evaluation proficiency and potentially decrease training costs.

Radiologic Imaging of Lung Cancer

Recent advances in technology like faster, high resolution CT scanners, new data in lung cancer screening combined with many changes in the classification, staging and novel therapies for lung cancer are redefining the role imaging plays in detection, staging and management of the disease. This chapter describes the utility and limitations of the different radiological modalities in various stages of the disease. Since it is the mainstay in lung cancer management emphasis is placed on the application of CT imaging. PET-CT has been discussed separately in this volume.