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We describe the transition-metal-free coupling for polyfluoroalkoxy arenes using polyfluoroalkoxy borates, which serve as counterions to diaryliodonium salts and transferring mediators of polyfluoroalkoxy groups. This strategy demonstrates high functional group compatibility owing to the low nucleophilicity of the borate mediator, thus offering a practical approach for synthesizing diverse polyfluoroalkoxy arenes. [ABSTRACT FROM AUTHOR]

Background: Ionoacoustics is a promising approach to reduce the range uncertainty in proton therapy. A miniature‐sized optical hydrophone (OH) was used as a measuring device to detect weak ionoacoustic signals with a high signal‐to‐noise ratio in water. However, further development is necessary to prevent wave distortion because of nearby acoustic impedance discontinuities while detection is conducted on the patient's skin. Purpose: A prototype of the probe head attached to an OH was fabricated and the required dimensions were experimentally investigated using a 100‐MeV proton beam from a fixed‐field alternating gradient accelerator and k‐Wave simulations. The beam range of the proton in a tissue‐mimicking phantom was estimated by measuring γ‐waves and spherical ionoacoustic waves with resonant frequency (SPIRE). Methods: Four sizes of probe heads were fabricated from agar blocks for the OH. Using the prototype, the γ‐wave was detected at distal and lateral positions to the Bragg peak on the phantom surface for proton beams delivered at seven positions. For SPIRE, independent measurements were performed at distal on‐ and off‐axis positions. The range positions were estimated by solving the linear equation using the sensitive matrix for the γ‐wave and linear fitting of the correlation curve for SPIRE; they were compared with those measured using a film. Results: The first peak of the γ‐wave was undistorted with the 3 × 3 × 3‐cm3 probe head used at the on‐axis and 3‐cm off‐axis positions. The range positions estimated by the γ‐wave agreed with the film‐based range in the depth direction (the maximum deviation was 0.7 mm), although a 0.6–2.1 mm deviation was observed in the lateral direction. For SPIRE, the deviation was <1 mm for the two measurement positions. Conclusions: The attachment of a relatively small‐sized probe head allowed the OH to measure the beam range on the phantom surface. [ABSTRACT FROM AUTHOR]

Background: Immunoglobulin (Ig)G4-related disease affects nearly every organ, and its clinical course varies depending on the involved organ; however, its occurrence in the mediastinum is rarely reported. Case presentation: A 58-year-old woman presented with a posterior mediastinal tumor along the thoracic spine on imaging. Based on her elevated serum IgG4 level of 349.7 mg/dL, IgG4-related disease was suspected. Since the tumor was growing and malignancy could not be excluded, surgical resection was performed for definitive diagnosis. Robot-assisted thoracoscopic surgery was performed via the left semipronation and right thoracic approaches. The irregularly-shaped tumor was located on the level of the seventh to ninth thoracic vertebra, along the sympathetic nerve. A malignancy was not excluded based on the appearance of the tumor. The tumor had poor mobility. The sympathetic nerves, intercostal arteries, and veins were also excised. In this case, the articulated forceps, used during the robotic surgery, were useful in achieving complete tumor resection along the vertebral body. The pathological examination revealed IgG4-positive plasma infiltration, which fulfilled the criteria for IgG4-related diseases. The postoperative course was uneventful, and the patient underwent follow-up on an outpatient basis without additional medications. Conclusion: The clinical presentation of IgG4-related disease varies, based on the involved organs. This case was rare because the mediastinum was involved, and it emphasized the effectiveness of surgical resection. [ABSTRACT FROM AUTHOR]

Background: Organ‐at‐risk (OAR) sparing is often assessed using an overlap volume‐based parameter, defined as the ratio of the volume of OAR that overlaps the planning target volume (PTV) to the whole OAR volume. However, this conventional overlap‐based predictive parameter (COPP) does not consider the volume relationship between the PTV and OAR. Purpose: We propose a new overlap‐based predictive parameter that consider the PTV volume. The effectiveness of proposed overlap‐based predictive parameter (POPP) is evaluated compared with COPP. Methods: We defined as POPP = (overlap volume between OAR and PTV/OAR volume) × (PTV volume/OAR volume). We generated intensity modulated radiation therapy (IMRT) based on step and shoot technique, and volumetric modulated arc therapy (VMAT) plans with the Auto‐Planning module of Pinnacle3 treatment planning system (v14.0, Philips Medical Systems, Fitchburg, WI) using the American Association of Physicists in Medicine Task Group (TG119) prostate phantom. The relationship between the position and size of the prostate phantom was systematically modified to simulate various geometric arrangements. The correlation between overlap‐based predictive parameters (COPP and POPP) and dose‐volume metrics (mean dose, V70Gy, V60Gy, and V37.5 Gy for rectum and bladder) was investigated using linear regression analysis. Results: Our results indicated POPP was better than COPP in predicting intermediate‐dose metrics. The bladder results showed a trend similar to that of the rectum. The correlation coefficient of POPP was significantly greater than that of COPP in < 62 Gy (82% of the prescribed dose) region for IMRT and in < 55 Gy (73% of the prescribed dose) region for VMAT regarding the rectum (p < 0.05). Conclusions: POPP is superior to COPP for creating predictive models at an intermediate‐dose level. Because rectal bleeding and bladder toxicity can be associated with intermediate‐doses as well as high‐doses, it is important to predict dose‐volume metrics for various dose levels. POPP is a useful parameter for predicting dose‐volume metrics and assisting the generation of treatment plans. [ABSTRACT FROM AUTHOR]

The SyncTraX series enables real-time tumor-tracking radiotherapy through the real-time recognition of a fiducial marker using fluoroscopic images. In this system, the isocenter should be located within approximately 5–7.5 cm from the marker, depending on the version, owing to the limited field of view. If the marker is placed away from the tumor, the isocenter should be shifted toward the marker. This study aimed to investigate stereotactic body radiotherapy (SBRT) outcomes of primary liver tumors treated with SyncTraX in cases where the isocenter was shifted marginally or outside the planning target volume (PTV). Twelve patients with 13 liver tumors were included in the analysis. Their isocenter was shifted toward the marker and was placed marginally or outside the PTV. The prescribed doses were generally 40 Gy in four fractions or 48 Gy in eight fractions. The overall survival (OS) and local control (LC) rates were calculated using the Kaplan–Meier method. All patients completed the scheduled SBRT. The median distance between the fiducial marker and PTV centroid was 56.0 (interquartile range [IQR]: 52.7–66.7) mm. By shifting the isocenter toward the marker, the median distance between the marker and isocenter decreased to 34.0 (IQR: 33.4–39.7) mm. With a median follow-up period of 25.3 (range: 6.9–70.0) months, the 2-year OS and LC rates were 100.0% (95% confidence interval: 100–100). An isocenter shift makes SBRT with SyncTraX feasible in cases where the fiducial marker is distant from the tumor. [ABSTRACT FROM AUTHOR]

Background Purpose Methods Results Conclusion Respiratory motion management is essential in order to achieve high‐precision radiotherapy. Markerless motion tracking of tumor can provide a non‐invasive way to manage respiratory motion, thereby enhancing treatment accuracy. However, the low contrast in real‐time x‐ray images for image guidance limits the application of markerless tracking.We present a novel approach based on a motion model to perform markerless tracking of tumor and surrounding tissues even when they have low contrast in real‐time x‐ray images.A proof‐of‐concept validation of the method has been performed using digital and physical phantoms at breathing conditions that are significantly different than the planning stage. A motion model is first constructed by performing principal component analysis (PCA) on the planning 4DCT. During treatment, the motion of a surrogate is tracked and used as the input of the motion model, which generates a 3D real‐time volume estimation. Such 3D estimation is then projected to 2D to create digitally reconstructed radiographs (DRRs). The relationships between the real‐time DRRs, reference DRRs, and reference x‐ray images are first established to simulate 2D real‐time images from the real‐time volume. The registration between the simulated 2D real‐time images and real‐time x‐ray images corrects the initial motion model estimation to ensure the estimated volume matches the real‐time condition.In digital phantom, the Dice index of pancreas was improved from 0.74 to 0.78 after correction using real‐time DRRs in fully inhaled phase. Validation on lung and pancreas is performed in physical phantom with two motion traces. The surrogate‐tumor relationships were intentionally altered to generate large target localization errors due to the differences in body condition between treatment planning stage and during treatment. The real‐time correction for the estimated 3D real‐time volume was performed using a pair of 2D x‐ray images. For the deep breathing motion trace, the tumor localization mean absolute error (MAE) throughout the tracking decreases from around 3 mm to less than 1 mm after correction. For the shallow breathing motion trace with a 1.7 mm baseline shift, the tumor localization MAE throughout the tracking decreases from around 1.5 mm to less than 1 mm after correction.The method combines the detailed structural information from planning 4DCT and real‐time information from real‐time x‐ray images through a motion model. The matching between the real‐time model estimation and 2D real‐time images is performed in the same modality so that it can be applied to regions with low contrast in the images. The real‐time images successfully corrected the initial motion model estimations in our proof‐of‐concept validation. This suggests the potential to perform markerless tracking in low‐contrast region using a motion model. [ABSTRACT FROM AUTHOR]

Background: Although lenvatinib is effective for unresectable thyroid carcinoma, it may cause adverse events owing to rapid tumor shrinkage or necrosis. Pneumothorax during lenvatinib therapy is rare. However, once it occurs, it can become a refractory and fatal complication. Herein, we report two cases of thyroid carcinoma with malignant pleurisy treated with lenvatinib and discuss treatment strategies to prevent pneumothorax., Case Description: The first case involved a 78-year-old male with papillary thyroid carcinoma and malignant bilateral pleural effusion. He underwent pleurodesis with talc for the left pleural effusion due to respiratory distress, and lenvatinib therapy was initiated. Forty days after lenvatinib therapy, the patient developed a right pneumothorax and underwent surgery for a prolonged air leak. However, the left pneumothorax was prevented by pleurodesis. During surgery, the visceral pleura was fragile, and repair of the pulmonary fistula was difficult. Pathological examination revealed an anaplastic carcinoma in the visceral pleura. The air leak disappeared 20 days after surgery; however, the patient died 22 days after surgery due to progression of the underlying disease. The second case involved a 65-year-old female with a poorly differentiated thyroid carcinoma and lung metastasis. She underwent ablation with 30 mCi 131 I after total thyroidectomy, and there was no accumulation in the metastatic sites. Chest computed tomography (CT) revealed the progression of malignant pleurisy in the right thoracic cavity, and iodine-resistant disease was confirmed. She was treated with lenvatinib after talc pleurodesis and showed good progress without any adverse events., Conclusions: The presence of malignant pleurisy results in a risk of developing lenvatinib-associated pneumothorax. Therefore, pleurodesis should be considered before lenvatinib therapy for thyroid carcinomas with malignant pleurisy., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-24-269/coif). The authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)

To assess the interfractional anatomical range variations (ARVs) with beam directions and their impact on dose distribution in intensity modulated proton therapy, we analyzed water equivalent thickness (WET) from 10 patients with pancreatic cancer. The distributions of the interfractional WET difference ($\Delta{\mathrm{WET}}^{\theta }$) across 360° were visualized using polar histograms. Interfractional ARVs were evaluated using the mean absolute error and ΔWET pass rate, indicating the percentage of $\Delta \mathrm{WE}{\mathrm{T}}^{\theta }$ < thresholds. The impact on dose distribution in proton therapy was evaluated based on two treatment plans for 40 Gy(RBE)/5 fractions: 'Plan A', using two beam angles, in which the target was closest to the body surface among four perpendicular directions; and 'Plan B', using two beam angles with small ARVs. Analysis revealed individual variations in angular trends of interfractional ARVs. Three distinct trends were identified: Group 1 exhibited small ARVs around posterior directions; Group 2 exhibited small ARVs except ~60°; Group 3 demonstrated minimal ARVs only ~90°. In dose evaluation, while 150° and 210° were selected in Plan B for 9 out of 10 patients, for the remaining patient, 60° and 90° were chosen. Comparing dose volume histogram parameters for all patients, Plan B significantly reduced target coverage loss while maintaining organ-at-risk sparing comparable to Plan A. These results demonstrated that selecting beam angles with small interfractional ARVs for each patient enhances the robustness of dose distribution, reducing target coverage loss., (© The Author(s) 2024. Published by Oxford University Press on behalf of The Japanese Radiation Research Society and Japanese Society for Radiation Oncology.)

Diaryliodonium(III) salts are versatile reagents that exhibit a range of reactions, both in the presence and absence of metal catalysts. In this study, we developed efficient synthetic methods for the preparation of aryl(TMP)iodonium(III) carboxylates, by reaction of (diacetoxyiodo)arenes or iodosoarenes with 1,3,5-trimethoxybenzene in the presence of a diverse range of organocarboxylic acids. These reactions were conducted under mild conditions using the trimethoxyphenyl (TMP) group as an auxiliary, without the need for additives, excess reagents, or counterion exchange in further steps. These protocols are compatible with a wide range of substituents on (hetero)aryl iodine(III) compounds, including electron-rich, electron-poor, sterically congested, and acid-labile groups, as well as a broad range of aliphatic and aromatic carboxylic acids for the synthesis of diverse aryl(TMP)iodonium(III) carboxylates in high yields. This method allows for the hybridization of complex bioactive and fluorescent-labeled carboxylic acids with diaryliodonium(III) salts., (Copyright © 2024, Miyamoto et al.)