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During the last decade, imaging has become the cornerstone for noninvasive diagnosis of different disorders and is currently being used by physicians all over the world. With the emergence of novel advanced imaging techniques that allow microstructural as well as functional tissue characterization along with the extensive work done by The Cancer Genome Atlas focusing on mapping genomic changes in glioblastoma, new correlations have been discovered between alterations at the genomics level and radiological imaging features in cancer patients. This has marked the beginning of a new era in clinical sciences, the era of "imaging genomics," which aims at establishing relationship between radiological imaging features and genomic characteristics of tumors. This article reviews the fundamentals of imaging genomics in glioma, its role in noninvasive genomic detection, and its future potential in personalized treatment planning. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To investigate the accuracy of M staging (staging of metastatic disease) in esophageal carcinoma based on a visual interpretation and based on tumor volume measurements on positron emission tomography (PET) computed tomography (CT). Materials and Methods: Fifty-nine untreated patients with gastroesophageal junction tumors were enrolled, including 36 subcardial gastric tumors (type III according to Siewert classification) and 23 adenocarcinomas of the cardia (AEG, type II Siewert). Patients were grouped in metastasis free (M0 stage, n = 34) and metastatic stages (M1 stage, n = 25). Tumor volume and mean and maximum standardized uptake value were measured on PET-CT. The accuracy of these quantitative tumor volume parameters in distinguishing metastasis-free tumors (M0 stage) from metastatic stages (M1 stage) was compared to the accuracy of a visual analysis with fused PET-CT. Furthermore, accuracy of PET-CT was compared to PET reviewed side by side with CT in a lesion-based analysis of 84 distant metastatic sites. Results: In the visual interpretation, PET-CT (accuracy 88%, 74/84) was more accurate than PET (accuracy 78%, 66/84; P = .008) in characterizing the 84 potential metastatic sites in the 59 patients. Among the tumor parameters, the PET-CT tumor volume was the most accurate predictor of M1 stage and overall survival. With a threshold of 39 mL, PET-CT volume was able to predict M1 stage disease with a sensitivity of 96% and a specificity of 85%. The accuracy of M-staging was increased further when combining tumor volume measurements with the results from the visual analysis (combined results: sensitivity 96%, specificity 94%). Conclusions: PET-CT was more accurate than PET (reviewed side by side with CT) in characterizing distant metastatic sites of gastroesophageal junction carcinomas. The highest accuracy for M-staging was obtained when combining the results of the visual analysis with the results from primary tumor volume measurements. Primary tumor volume was shown to be an independent prognostic factor. [Copyright &y& Elsevier]

Background: Previous studies demonstrated that a decrease of the standardized uptake value between pretreatment and posttreatment positron emission tomography (PET) scans can predict histopathologic treatment response in patients with esophageal cancer. Methods: Forty-seven patients who underwent PET–computed tomography (CT) scans before (scan 1) and after (scan 2) neoadjuvant chemoradiotherapy and during the follow-up period after surgery (scan 3) were included in this study. It was evaluated whether decrease of metabolic tumor length between scan 1 and scan 2 can predict histopathologic response to treatment. Moreover, the value of PET-CT was compared with PET in the assessment of tumor recurrence based on a visual analysis of scan 3. Reference standards for treatment response and recurrence were histopathology results. Results: The reduction of tumor length between before and after chemoradiotherapy scans (between scan 1 and scan 2) was a better predictor of histopathologic response and of time to recurrence than the decrease in standardized uptake value. The most accurate differentiation was achieved when using a cut-off value of 33% reduction of the initial tumor length. Using this threshold to define metabolic response, the sensitivity was 91% (19 of 21) and the specificity was 92% (24 of 26) for predicting histopathologic treatment response. Based on a visual analysis, PET-CT was more accurate than PET in the differentiation of tumor recurrence from posttreatment tissue changes. Integrated PET-CT achieved a sensitivity of 91% (48 of 53) and a specificity of 81% (30 of 37) in identifying sites of tumor recurrence, compared with 83% (44 of 53) and 65% (24 of 37) with PET. Conclusions: Decrease of tumor length was shown to be a better predictor of treatment response and disease-free survival than decrease of standardized uptake value. Furthermore, PET-CT is more accurate in the evaluation of recurrence than PET. [Copyright &y& Elsevier]

Multidetector computed tomography (MDCT) is expected to revolutionize the way the evaluation and work-up of the cardiac patient is performed. Although invasive coronary and cardiac angiography maintains a 0.2-mm spatial resolution versus 0.4-mm in 64-slice MDCT, the emergence of retrospectively electrocardiographic-gated 64-slice MDCT has resulted in high spatial resolutions that are not achievable with other noninvasive cardiac imaging modalities. The purpose of this article is to describe the MDCT qualitative techniques used to evaluate valvular lesions and to describe and illustrate a spectrum of congenital and acquired valvular disease with 64-slice MDCT. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study was to investigate the potential of a head and neck magnetic resonance simulation and immobilization protocol on reducing motion-induced artifacts and improving positional variance for radiation therapy applications. Methods and materials Two groups (group 1, 17 patients; group 2, 14 patients) of patients with head and neck cancer were included under a prospective, institutional review board–approved protocol and signed informed consent. A 3.0-T magnetic resonance imaging (MRI) scanner was used for anatomic and dynamic contrast-enhanced acquisitions with standard diagnostic MRI setup for group 1 and radiation therapy immobilization devices for group 2 patients. The impact of magnetic resonance simulation/immobilization was evaluated qualitatively by 2 observers in terms of motion artifacts and positional reproducibility and quantitatively using 3-dimensional deformable registration to track intrascan maximum motion displacement of voxels inside 7 manually segmented regions of interest. Results The image quality of group 2 (29 examinations) was significantly better than that of group 1 (50 examinations) as rated by both observers in terms of motion minimization and imaging reproducibility ( P < .0001). The greatest average maximum displacement was at the region of the larynx in the posterior direction for patients in group 1 (17 mm; standard deviation, 8.6 mm), whereas the smallest average maximum displacement was at the region of the posterior fossa in the superior direction for patients in group 2 (0.4 mm; standard deviation, 0.18 mm). Compared with group 1, maximum regional motion was reduced in group 2 patients in the oral cavity, floor of mouth, oropharynx, and larynx regions; however, the motion reduction reached statistical significance only in the regions of the oral cavity and floor of mouth ( P < .0001). Conclusions The image quality of head and neck MRI in terms of motion-related artifacts and positional reproducibility was greatly improved by use of radiation therapy immobilization devices. Consequently, immobilization with external and intraoral fixation in MRI examinations is required for radiation therapy application. [ABSTRACT FROM AUTHOR]