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In this article, the multidisciplinary team of the Taiwan Academy of Tumor Ablation, who have expertise in treating lung cancer, present their perspectives on percutaneous image‐guided thermal ablation (IGTA) of lung tumors. The modified Delphi technique was applied to reach a consensus on clinical practice guidelines concerning ablation procedures, including a comprehensive literature review, selection of panelists, creation of a rating form and survey, and arrangement of an in‐person meeting where panelists agreed or disagreed on various points. The conclusion was a final rating and written summary of the agreement. The multidisciplinary expert team agreed on 10 recommendations for the use of IGTA in the lungs. These recommendations include terms and definitions, line of treatment planning, modality, facility rooms, patient anesthesia settings, indications, margin determination, post‐ablation image surveillance, qualified centers, and complication ranges. In summary, IGTA is a safe and feasible approach for treating primary and metastatic lung tumors, with a relatively low complication rate. However, decisions regarding the ablation technique should consider each patient's specific tumor characteristics. [ABSTRACT FROM AUTHOR]

Purpose: To explore the utility of integrated positron emission tomography (PET) / magnetic resonance imaging (MRI) for evaluating subclinical inflammation in patients with ulcerative colitis (UC).Materials and Methods: This prospective study was approved by the Institutional Review Board and informed consent was obtained. Between November 2015 and April 2016, 19 consecutive patients with UC in clinical remission were enrolled. These patients underwent 18F-fluorodeoxyglucose PET/MRI (3T) and colonoscopy. Serum high-sensitivity C-reactive protein (hs-CRP) and fecal calprotectin (FC) levels were also obtained. The findings of colonoscopy were graded using the Mayo endoscopic subscore. Quantitative (minimum apparent diffusion coefficient [ADCmin ] and maximum standardized uptake value [SUVmax ]), semiquantitative, and qualitative parameters of PET/MRI were evaluated and correlated with colonoscopic findings.Results: In per-segment analysis, ADCmin was significantly lower and SUVmax and ratio of SUVmax to ADCmin were significantly higher in the colonic segments with active inflammation (Mayo endoscopic subscore ≥2) (P < 0.05). Qualitative MRI score, PET activity grade, and PET/MRI score were also significantly higher in the colonic segments with active inflammation (P < 0.05). Among these parameters, the ratio of SUVmax to ADCmin exhibited the highest area under the receiver operating characteristic curve (AUC) (0.763). In per-patient analysis, the AUC of PET activity grade was 0.778, higher than those of hs-CRP (0.589) and FC (0.722). Using a combined index of FC and PET, an even higher AUC (0.867) was achieved.Conclusion: PET/MRI is a potentially useful tool in identifying subclinical inflammation in patients with UC.Level Of Evidence: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:737-745. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the response in patients undergoing SBRT using dynamic contrast-enhanced (DCE) integrated magnetic resonance positron emission tomography (MR-PET). Stereotactic body radiation therapy (SBRT) is efficacious as a front-line local treatment for non-small cell lung cancer (NSCLC).Materials and Methods: We prospectively enrolled 19 lung tumors in 17 nonmetastatic NSCLC patients who were receiving SBRT as a primary treatment. They underwent DCE-integrated 3T MR-PET before and 6 weeks after SBRT. The following image parameters were analyzed: tumor size, standardized uptake value (SUV), apparent diffusion coefficient, Ktrans , kep , ve , vp , and iAUC60 . Chest computed tomography (CT) was performed at 3 months after SBRT.Results: SBRT treatment led to tumor changes including significant decreases in the SUVmax (-61%, P < 0.001), Ktrans mean (-72%, P = 0.005), Ktrans standard deviation (SD; -85%, P = 0.046), kep mean (-53%, P = 0.014), kep SD (-63%, P = 0.001), and vp SD (-58%, P = 0.002). The PET SUVmax was correlated with the MR kep mean (P = 0.002) and kep SD (P < 0.001). The percentage reduction in Ktrans mean (P < 0.001) and kep mean (P = 0.034) at 6 weeks post-SBRT were significantly correlated with the percentage reduction in tumor size, as measured using CT at 3 months after SBRT. Univariate analyses revealed a trend toward disease progression when the initial SUVmax > 10 (P = 0.083).Conclusion: In patients with NSCLC who are receiving SBRT, DCE-integrated MR-PET can be used to evaluate the response after SBRT and to predict the local treatment outcome.Level Of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:191-199. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the treatment response of locally advanced breast cancer (LABC) to neoadjuvant chemotherapy using magnetic resonance (MR) vascular maps and apparent diffusion coefficient (ADC) at 3T. Materials and Methods Thirty-one patients with LABC who underwent breast MR studies before, after the first course, and after completing neoadjuvant chemotherapy were enrolled. Vascular morphology was retrieved via Hessian matrix and the voxels of the vessels and volume of vessels were measured automatically. Whole tumor mean ADC values were calculated. Clinical responders were defined as >50% tumor reduction in the final MR studies. Pathologically complete responders were also recorded.Results: There were 21 clinical responders and 10 nonresponders. Compared to the nonresponders after the first course, the responders were characterized by more vascular reduction of the breast lesion and decreased bilateral vascular discrepancy (voxels and volume), and increments in the ADC value and ADC percentage of the lesions (all P < 0.05). There were three pathological complete responders who showed more apparent early vascular reduction of the lesion breast (voxels and volume) and increments in the ADC value than others (P = 0.02, 0.01 and 0.02, respectively).Conclusion: The early changes of MR vascular maps and ADC are associated with the final treatment response of LABC. [ABSTRACT FROM AUTHOR]

Purpose: To investigate dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) of advanced nonsmall-cell lung cancer (NSCLC) patients treated with the antiangiogenic agent bevacizumab combined with gemcitabine and cisplatin as first-line treatment. Materials and Methods: All patients were enrolled for MRI and computed tomography (CT) before and after the first three courses of bevacizumab combination chemotherapy. Pharmacokinetic parameters ( Ktrans, kep, ve, vp) derived from DCE MRI were computed for the main mass. Parametric histogram analysis was obtained to evaluate changes of the internal tumor composition and for correlation with tumor response measured on CT. Results: After three cycles of treatment, 11 patients showed decreased tumor size and a decreased value of all MR-derived pharmacokinetic parameters. Among these parameters, there was a significant decrease of mean and standard deviation of the Ktrans histogram as well as a decrease of mean of the k ep histogram ( P < 0.05). Tumors with larger mean values of rate constant k ep ( P < 0.0001) and smaller standard deviation of volume of extravascular extracellular space fraction v e ( P < 0.0001) on histograms before chemotherapy were considered predictors for treatment response. Conclusion: DCE MRI enables a functional analysis of the treatment response of NSCLC. MRI parametric histogram has the potential to predict early treatment response of combined bevacizumab, gemcitabine, and cisplatin. J. Magn. Reson. Imaging 2012;36:387-396. ©2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Purpose: A probabilistic image segmentation algorithm called stochastic region competition is proposed for performing Doppler sonography segmentation. Methods: The image segmentation is conducted by maximizing a posteriori that models histogram likelihood, gradient likelihood, and a spatial prior. The optimization is done by a modified expectation and maximization (EM) method that aims to improve computation efficiency and avoid local optima. Results: The algorithm was tested on 155 color Doppler sonograms and compared with manual delineations. The qualitative assessment shows that our algorithm is able to segment mass lesions under the condition of low image quality and the interference of the color-encoded Doppler information. The quantitative assessment analysis shows that the average distance between the algorithm-generated boundaries and manual delineations is statistically comparable to the variability of manual delineations. The ratio of the overlapping area between the algorithm-generated boundaries and manual delineations is also comparable to that between different sets of manual delineations. A reproductivity test was conducted to confirm that the result is statistically reproducible. Conclusions: The algorithm can be used to perform Doppler sonography segmentation and to replace the tedious manual delineation task in clinical application. [ABSTRACT FROM AUTHOR]

Lin T-C, Chen S-U, Chen Y-F, Chang Y-C & Lin C-W (2012) Histopathology 60, 287-295 Intramucosal variant of nasal natural killer (NK)/T cell lymphoma has a better survival than does invasive variant: implication on loss of E26 transformation-specific sequence 1 (ETS-1) and T-box expressed in T cells (T-bet) with invasion Aims: Nasal natural killer/T cell lymphoma (NNKTCL) arises from the nasal mucosa, and spreads to adjacent tissues via local invasion or to regional lymph nodes and distant sites via metastasis. The aims of this study were to determine the impact of invasion on the prognosis of NNKTCL, and correlate invasion with the expression of cytotoxic markers of lymphoma cells. Methods and results: Histopathological evaluations of invasion and immunohistochemistry for cytotoxic markers, including E26 transformation-specific sequence 1 (ETS-1), T-box expressed in T cells (T-bet), signal transducer and activator of transcription (STAT-1), CD56 and granzyme B (GB), were performed in 64 NNKTCLs. There were 17 stage I cases without invasion (stage Ia or intramucosal), 21 stage I cases with invasion (stage Ib), 16 stage II cases and 10 stages III/IV cases. Stage Ia NNKTCLs had a better 5-year overall survival rate than that of stages Ib, II or III/IV NNKTCLs (85%, 38%, 33% and 20%, respectively, P < 0.001 by log-rank test). Loss of ETS-1 was found in 24% (four of 17) stage Ia NNKTCLs and in 65% (28 of 43) stages Ib/II/III/IV NNKTCLs ( P = 0.04, Fisher's exact test); loss of T-bet was found in 29% (five of 17) stage Ia NNKTCLs and in 67% (30 of 45) stages Ib/II/III/IV NNKTCLs ( P = 0.02, Fisher's exact test). Conclusions: NNKTCL is classically an aggressive lymphoma, but the intramucosal variant is less aggressive. Loss of ETS-1 or T-bet correlated weakly with invasion, a finding that requires further confirmation. [ABSTRACT FROM AUTHOR]

Purpose: Fully automatic and high-quality demarcation of sonographical breast lesions remains a far-reaching goal. This article aims to develop an image segmentation algorithm that provides quality delineation of breast lesions in sonography with a simple and friendly semiautomatic scheme. Methods: A data-driven image segmentation algorithm, named as augmented cell competition (ACCOMP) algorithm, is developed to delineate breast lesion boundaries in ultrasound images. Inspired by visual perceptual experience and Gestalt principles, the ACCOMP algorithm is constituted of two major processes, i.e., cell competition and cell-based contour grouping. The cell competition process drives cells, i.e., the catchment basins generated by a two-pass watershed transformation, to merge and split into prominent components. A prominent component is defined as a relatively large and homogeneous region circumscribed by a perceivable boundary. Based on the prominent component tessellation, cell-based contour grouping process seeks the best closed subsets of edges in the prominent component structure as the desirable boundary candidates. Finally, five boundary candidates with respect to five devised boundary cost functions are suggested by the ACCOMP algorithm for user selection. To evaluate the efficacy of the ACCOMP algorithm on breast lesions with complicated echogenicity and shapes, 324 breast sonograms, including 199 benign and 125 malignant lesions, are adopted as testing data. The boundaries generated by the ACCOMP algorithm are compared to manual delineations, which were confirmed by four experienced medical doctors. Four assessment metrics, including the modified Williams index, percentage statistic, overlapping ratio, and difference ratio, are employed to see if the ACCOMP-generated boundaries are comparable to manual delineations. A comparative study is also conducted by implementing two pixel-based segmentation algorithms. The same four assessment metrics are employed to evaluate the boundaries generated by two conventional pixel-based algorithms based on the same set of manual delineations. Results: The ACCOMP-generated boundaries are shown to be comparable to the manual delineations. Particularly, the modified Williams indices of the boundaries generated by the ACCOMP algorithm and the first and second pixel-based algorithms are 1.069±0.024, 0.935±0.024, and 0.579±0.013, respectively. If the modified Williams index is greater than or equal to 1, the average distance between the computer-generated boundaries and manual delineations is deemed to be comparable to that between the manual delineations. Conclusions: The boundaries derived by the ACCOMP algorithm are shown to reasonably demarcate sonographic breast lesions, especially for the cases with complicated echogenicity and shapes. It suggests that the ACCOMP-generated boundaries can potentially serve as the basis for further morphological or quantitative analysis. [ABSTRACT FROM AUTHOR]

Purpose: To develop an intensity inhomogeneity algorithm for breast sonograms in order to assist visual identification and automatic delineation of lesion boundaries. Methods: The proposed algorithm was composed of two essential ideas. One was decomposing the region of interest (ROI) into foreground and background regions by a cell-based segmentation algorithm, called constrained fuzzy cell-based bipartition-EM (CFCB-EM) algorithm. The CFCB-EM algorithm deformed the contour in a fuzzy cell-based deformation fashion with the cell structures derived by the fuzzy cell competition (FCC) algorithm as the deformation unit and the boundary estimated by the normalized cut (NC) algorithm as the reference contour. The other was modeling the intensity inhomogeneity in an ROI as a spatially variant normal distribution with a constant variance and spatially variant means, which formed a polynomial surface of order n. The proposed algorithm was formulated as a nested EM algorithm comprising the outer-layer EM algorithm, i.e., the intensity inhomogeneity correction-EM (IIC-EM) algorithm, and the inner-layer EM algorithm, i.e., the CFCB-EM algorithm. The E step of the IIC-EM algorithm was to provide a reasonably good bipartition separating the ROI into foreground and background regions, which included three major component algorithms, namely, the FCC, the NC, and the CFCB-EM. The M step of the IIC-EM algorithm was to estimate and correct the intensity inhomogeneity field by least-squared fitting the intensity inhomogeneity to an nth order polynomial surface. Forty-nine breast sonograms with intensity inhomogeneity, each from a different subject, were randomly selected for performance analysis. Three assessments were carried out to evaluate the effectiveness of the proposed algorithm. Results: Based on the visual evaluation of two experienced radiologists, in the first assessment, 46 out of 49 breast lesions were considered to have better contrasts on the inhomogeneity-corrected images by both radiologists. The interrater reliability for the radiologists was found to be kappa=0.479 (p=0.001). In the second assessment, the mean gradients of the low-gradient boundary points before and after correction of the intensity inhomogeneity were compared by the paired t-test, yielding a p-value of 0.000, which suggested the proposed intensity inhomogeneity algorithm may enhance the mean gradient of the low-gradient boundary points. By using the paired t-test, the third assessment further showed that the Chan and Vese level set method could derive a much better lesion boundary on the inhomogeneity-corrected image than on the original image (p=0.000). Conclusions: The proposed intensity inhomogeneity correction algorithm could not only augment the visibility of lesion boundary but also improve the segmentation result on a breast sonogram. [ABSTRACT FROM AUTHOR]