Log file–based methods are attracting increasing interest owing to their ability to validate volumetric-modulated arc therapy outputs with high resolution in the leaf and gantry positions and in delivered dose. Cross-validation of these methods for comparison with measurement-based methods using the ionization chamber/ArcCHECK-3DVH software (version 3.2.0) under the same conditions of treatment anatomy and plan enables an efficient evaluation of this method. In this study, with the purpose of cross-validation, we evaluate the accuracy of a log file–based method using Elekta log files and an X-ray voxel Monte Carlo dose calculation technique in the case of leaf misalignment during prostate volumetric-modulated arc therapy. In this study, 10 prostate volumetric-modulated arc therapy plans were used. Systematic multileaf collimator leaf positional errors (±0.4 and ±0.8 mm for each single bank) were deliberately introduced into the optimized plans. Then, the delivered 3-dimensional doses to a phantom with a certain patient anatomy were estimated by our system. These doses were compared with the ionization chamber dose and the ArcCHECK-3DVH dose. For the given phantom and patient anatomy, the estimated dose strongly coincided with the ionization chamber/ArcCHECK-3DVH dose (P < .01). In addition, good agreement between the estimated dose and the ionization chamber/ArcCHECK-3DVH dose was observed. The dose estimation accuracy of our system, which combines Elekta log files and X-ray voxel Monte Carlo dose calculation, was evaluated.

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Granular cell myoblastoma of of the right main bronchus in a 5-year-old girl is reported. The tumor extended to the lower trachea from the right main bronchus which was occluded completely by the tumor. The diagnosis was established histologically by a obtaining bronchoscopic biopsy specimen. Right pneumonectomy was carried out to control pulmonary suppuration caused by the tumor obstruction of the bronchus. External radiotherapy and interstitial brachytherapy were successful to control the growth of the residual tumor. She has been free from symptoms for about 12 years after the treatment.

A previously healthy 58-year-old man was admitted for muscle pain and weakness [manual muscle testing (MMT) of 4/4 for upper and lower limbs]. We detected elevated levels of inflammatory makers and PR3-anti-neutrophil cytoplasmic antibody (ANCA). Subsequently, the muscle weakness rapidly progressed to an MMT of 2 for all limbs. Magnetic resonance imaging indicated muscle edema, and the creatine kinase (CK) level increased to 29,998 U/L. Methylprednisolone (mPSL) and cyclophosphamide pulse therapy improved the patient symptoms. MMT recovered to 4 for all limbs. A muscle biopsy showed degenerated muscle fibers surrounded by neutrophil-predominant infiltration. In addition, lamina elastic breakdown and fibrinoid necrosis of arterioles were observed. A final diagnosis of microscopic polyangiitis (MPA) limited to the muscles was made.

A case of a 55‐year‐old female patient with an oncocytic variety of carcinoid tumor of the lung is reported. Electron microscopic observation of marked hyperplasia and increase in number of mitochondria in the tumor cells suggested it to be of oncocytic variety and membrane bound electron dense granules were characteristically found in the tumor cells which were histologically diagnosed as carcinoid.