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This study evaluated the correlation between radiation-induced lung injury (RILI) and dosimetric parameters on computed tomography (CT) images of stage I non-small cell lung cancer (NSCLC) patients undergoing intensity-modulated radiotherapy (IMRT). Sixty-three stage I NSLC patients who underwent IMRT were enrolled in the study. The patients underwent CT within 6 months (acute phase) and 1.5 years (late phase) after radiotherapy. These were fused with the planned irradiation CT. The range of RILI was measured from 10% to 100%, with an IC in 10% increments. The median interval from completion of radiotherapy to acute and late phase CT was 92 and 440 days, respectively. The median RILI ranges of the acute and late phases were in the 80% (20–100%) and 70% dose regions (20–100%), respectively. The significantly narrower range of RILI when lung V20 in the acute phase was less than 19.2% and that of V5 in the late phase was less than 27.6% at the time of treatment planning. This study showed that RILI occurred in a localized range in stage I NSCLC patients who underwent IMRT. The range of RILI was correlated with V20 in the acute phase and V5 in the late phase. RILI correlated with V20 in acute and V5 in late phase. The shadow of RILI occurred in 80% dose region in acute and 70% in late phase. No relationship exists between radiographic changes in RILI and PTV volume. [ABSTRACT FROM AUTHOR]

Hypothyroidism may occur after definitive radiotherapy in rare cases of early glottic carcinoma. However, to the best of our knowledge, no study to date has examined the risk factors for hypothyroidism specifically after definitive radiotherapy in patients with early glottic carcinoma. The present study determined risk factors for hypothyroidism after definitive radiotherapy in patients with early glottic carcinoma. This was a retrospective study that included 73 patients with T1 or T2, N0 glottic squamous cell carcinoma who underwent radiotherapy between June 3, 2009 and December 25, 2020. Demographic and clinical characteristics, including age, sex, tumor stage and pretreatment thyroid volume, were examined to elucidate the clinical risk factors for hypothyroidism. Field size, total prescribed dose and thyroid receiving dose were evaluated as dosimetric risk factors for hypothyroidism. Irradiated underlying thyroid volumes of more than 5, 10, 20, 30, 40, 50, 60 and 65 Gy (V5Gy, V10Gy, V20Gy, V30Gy, V40Gy, V50Gy, V60Gy and V65Gy) and mean thyroid dose were included as thyroid receiving doses. The median follow-up duration was 61 months (range, 7–150 months). Hypothyroidism was present in 15 (21%) of the 73 patients, including 12 and 3 patients with grade 1 and 2 hypothyroidism, respectively. Among the demographic and clinical factors, sex and pretreatment thyroid volume were significantly associated with hypothyroidism (P=0.007 and P<0.001, respectively). Among the dosimetric factors, the presence of hypothyroidism was significantly associated with V5Gy (P=0.012), V10Gy (P=0.015), V20Gy (P=0.020), V30Gy (P=0.024), V40Gy (P=0.028), V50Gy (P=0.028), V60Gy (P=0.027) and mean thyroid dose (P=0.023). In conclusion, sex, pretreatment thyroid volume and thyroid receiving dose were associated with hypothyroidism after definitive radiotherapy in patients with early glottic carcinoma. Particularly, the receiving dose to the thyroid gland should be reduced in female patients and in those with small thyroid volumes who are at higher risk for hypothyroidism following radiotherapy. [ABSTRACT FROM AUTHOR]

One limitation is that they performed a single irradiation exposure to the salivary gland, despite the fact that patients who receive irradiation in the head and neck undergo fractionated irradiation. Xerostomia is one of the most frequent adverse events following irradiation in patients with head and neck carcinoma, which results from histological damage of the salivary glands and requires preventive and curative intervention both during and after their therapeutic course in long-term survivors.1 Although magnetic resonance imaging (MRI) is a noninvasive modality that can quantitatively reveal changes in histology, fibrosis, and perfusion in irradiated parotid glands,2-4 corresponding histological validation remains limited because of difficulties in harvesting sufficient histological samples to allow comprehensive investigations using experimental animal models by Chen et al.5 In the article by Chen et al in this issue of I JMRI i , they advanced our understanding of the relationship between submandibular gland pathology of experimental Sprague-Dawley rat with a single dose of 15 Gy irradiation and multiparametric MRI using 3T-MRI. Marzi et al reported that significant ADC changes occur between pre- and post-radiation therapy and discussed that ADC and D are dependent on the characteristics of glandular tissue.6 The data by Chen et al provide a comprehensive answer on the relationship between diffusion parameters and irradiated salivary glands. [Extracted from the article]

Objective: To investigate the positron emission tomography/computed tomography (PET/CT) findings of T1/T2N0M0 glottic cancer (hereafter referred to as T1/T2) and dose distribution in radiotherapy., Subjects and Methods: We retrospectively collected data from patients diagnosed with T1/T2N0M0 glottic cancer who received radiotherapy. The extent of fluorine-18-fluorodeoxyglucose ( 18 F-FDG) accumulation in primary tumors, maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), tumor volume of primary tumors on PET/CT were compared. Furthermore, the tumor identified on PET/CT was incorporated into the radiotherapy plans. A dummy plan (radiation field 6x6cm, prescription point facing the vertebral body, maximum dose ≤107%, T1/T2 66Gy/33 fractions) was developed for three-dimensional conformal radiotherapy, and the dose distribution of primary tumors was calculated., Results: Twenty-nine patients (27 men and two women) were included; their mean age was 67.2±15.0 years. Increased 18 F-FDG accumulation in primary tumors was observed on PET/CT in 22/29 (78.5%; T1: 14/21 [67%], T2: 8/8 [100%]) patients. The median SUVmax, TLG, and primary tumor volume were significantly different between T1 and T2 (SUVmax, T1: 4.56 vs. T2: 8.43, P=0.035; TLG, T1: 1.01 vs. T2: 3.71 SUVxmL, P<0.01; primary tumor volume, T1: 0.38mL vs. T2: 0.80mL, P=0.01). At a TLG cut-off value of 3.470, the area under the curve was 0.875, sensitivity was 0.875, and specificity was 0.929 for T1-T2 differentiation. In 20 patients with 18 F-FDG accumulation, the minimum radiation dose was significantly different between T1 and T2 (66Gy vs. 64Gy, P<0.01) at the same 66Gy prescription. The minimum radiation dose and primary tumor volume show the correlation value (r=-0.516, P=0.02)., Conclusion: In glottic cancer, T1 and T2 can be differentiated by the extent of 18 F-FDG accumulation in primary tumors on PET/CT. The minimum radiation dose rate decreases as volume increases.

Objectives: The study aimed to retrospectively investigate the apparent diffusion coefficient (ADC) of primary cervical cancer to examine the recurrence correlations in patients treated with radiotherapy (RT)., Methods: The ADC of 31 patients with cervical cancer treated with RT were analyzed as possible risk factors for recurrence. A receiver operating characteristic (ROC) curve of the mean ADC (ADCmean) for the recurrence was generated to determine the cut-off value that yielded optimal sensitivity and specificity. The patient population was subdivided according to the risk factors for recurrence, and the disease-free survival (DFS) was analyzed. The following were investigated to explore the risk factors for recurrence: age, performance status, stage, pelvic lymph node metastasis, histologic tumor grade, maximal diameter of the primary tumor, chemotherapy, and ADCmean., Results: The median follow-up duration of the patients was 25 months. The recurrence was recognized in 9 (29%) of the 31 cases. The ROC analysis of recurrence showed that the area under the ADCmean curve was 0.889 (95% CI, 0.771-1.000; p = 0.001). The cut-off value of ADC mean was 0.900 × 10 - 3 mm 2 /s, with a sensitivity of 86.4% and a specificity of 88.9%. By univariate analysis, the ADCmean was the only factor significantly associated with recurrence., Conclusion: The ADCmean of the primary tumor is a potential predictive factor for the recurrence in of cervical cancer., Advances in Knowledge: The ADCmean of the primary tumor is a predictor of recurrence in patients with pre-treatment cervical cancer evaluation., (© 2021 The Authors. Published by the British Institute of Radiology.)

Objective: I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane ( 123 I-FP-CIT) is well known to be a useful tracer for differentiating dementia with Lewy bodies (DLB) and Alzheimer disease (AD). However, clinically, there are some cases in which these diseases cannot be differentiated by ordinary quantitative methods. Therefore, in this study, we established an index that reflects not only the total count but also the distribution and heterogeneity of tracer uptake. We investigated whether assessment of the heterogeneous depletion of 123 I-FP-CIT is useful for the differentiation of various types of dementia, i.e., probable DLB, possible DLB, and AD, using texture analysis., Materials and Methods: A total of 122 patients with either probable DLB (n=35), possible DLB (n=23), AD (n=44), and normal controls (n=20) were analyzed. Summated single photon emission computed tomography (SPECT) images (7 to 10 slices) of the patients, including the bilateral striatum, were analyzed using the gray-level histogram method (GLHM) of texture analysis. Mean, variance, skewness, and kurtosis of GLHM were compared with the specific binding ratio by Livia Tossici-Bolt's method (SBR)., Results: The sensitivity and specificity for differentiating probable DLB from possible DLB, AD, and normal controls were 97.1% and 77.0%, respectively, for skewness, using a cut-off point of 6.8%, and 97.1% and 81.6%, respectively, for kurtosis, using a cut-off point of 53.4%. The sensitivity and specificity for differentiating probable and possible DLB from AD and normal controls was 65.5% and 98.4%, respectively, for skewness, using a cut-off point of 6.4%, and 79.3% and 93.8%, respectively, for kurtosis, using a cut-off point of 53.4%., Conclusion: In the assessment of the efficacy of 123 I-FP-CIT to differentiate AD and DLB subtypes, mean, variance, skewness, and kurtosis by GLHM was as useful as the SBR method. Moreover, possible DLB and probable DLB could be differentiated by skewness and kurtosis. Our results demonstrate that texture analysis is more useful than conventional quantitative methods for obtaining valuable information of the brain. Textural features as such may have considerable potential as imaging biomarkers of DLB progression.