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PURPOSE: The purpose of this study is to find essential risk factors associated with liver function (LF) deteriorations within fluctuating long-term LF and their time-varying effects in patients with hepatocellular carcinoma (HCC) receiving hepatic radiotherapy and to identify high-risk groups for adverse LF deteriorations and their changes over time in facilitating the prevention of hepatic decompensation and the improvement of survival. MATERIALS AND METHODS: A total of 133 HCC patients treated by hepatic radiotherapy were enrolled. A study design was conducted to convert posttreatment long-term LF with fluctuating levels over time to recurrent LF events using defined upgrades in a grading scale. The hazard ratios (HR) of pretreatment biochemical, demographic, clinical, and dosimetric factors in developing posttreatment LF events were estimated using the Cox model. Methodologies of the counting process approach, robust variance estimation, goodness-of-fit testing based on the Schoenfeld residuals, and time-dependent covariates in survival analysis were employed to handle the correlation within subjects and evaluate the time-varying effects during long-term follow-up. RESULTS: Baseline LF score before radiotherapy and gender were significant factors. Initial HR in developing LF events was 1.17 (95% CI 1.11-1.23; P < 0.001) for each increase of baseline LF score and kept almost constant over time (HR, 1.00; 95% CI 1.00-1.01; P = 0.065). However, no difference was observed regarding initial hazards for gender (HR, 1.00; 95% CI 0.64-1.56; P = 0.994), but the hazard for women got higher monthly over time compared with men (HR, 1.04; 95% CI 1.01-1.07; P = 0.006). CONCLUSIONS: High-risk groups for adverse LF deteriorations after hepatic radiotherapy may change over time. Patients with poor baseline LF are vulnerable from the beginning. Women require prevention strategies and careful monitoring for deteriorations at a later stage.

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For widespread cutaneous lymphoma, such as mycosis fungoides or leukemia cutis, in patients with acute myeloid leukemia (AML) and for chronic myeloproliferative diseases, total skin irradiation is an efficient treatment modality for disease control. Total skin irradiation aims to homogeneously irradiate the skin of the entire body. However, the natural geometric shape and skin folding of the human body pose challenges to treatment. This article introduces treatment techniques and the evolution of total skin irradiation. Articles on total skin irradiation by helical tomotherapy and the advantages of total skin irradiation by helical tomotherapy are reviewed. Differences among each treatment technique and treatment advantages are compared. Adverse treatment effects and clinical care during irradiation and possible dose regimens are mentioned for future prospects of total skin irradiation.

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The development of wearable devices provides approaches for the realization of self-health care. Easily carried wearable devices allow individual health monitoring at any place whenever necessary. There are various interesting monitoring targets, including body motion, organ pressure, and biomarkers. An efficient use of space in one small device is a promising resolution to increase the functions of wearable devices. Through integration of a microfluidic system into wearable devices, embedding complicated structures in one design becomes possible and can enable multifunction analyses within a limited device volume. This article reviews the reported microfluidic wearable devices, introduces applications to different biofluids, discusses characteristics of the design strategies and sensing principles, and highlights the attractive configurations of each device. This review seeks to provide a detailed summary of recent advanced microfluidic wearable devices. The overview of advanced key components is the basis for the development of future microfluidic wearable devices.

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Image-guided radiotherapy (IGRT) is an advanced auxiliary radiotherapy technique. During cancer treatment, patients with oral cavity cancer (OCC) experience not only disease but also adverse effects due to RT. IGRT provides the relevant advantages of RT by precisely delivering tumoricidal doses via real-time knowledge of the target volume location and achieves maximal tumor control with minimal complications as recommended for cancer treatment. Additionally, studies have shown that IGRT can improve clinical outcomes in terms of not only treatment side effects but also survival benefits for cancer patients. IGRT can be performed alongside various imaging methods, including computed tomography and magnetic resonance imaging, and at different times during the radiotherapy regimen. This article reviews the literature to discuss the effects and importance of IGRT for patients with OCC, examines the rationale underlying the advantages of IGRT, discusses the limitations of IGRT with respect to different techniques, and summarizes the strategies and future prospects of IGRT in the treatment of OCC.

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Objectives: Breast reconstruction helps patients enhance their body image after mastectomy. Metallic ports in tissue expanders lead to dose attenuation during radiotherapy. Tissue expander volume shifts the metallic port position, possibly causing various dose alterations. This study aimed to evaluate the impact of the MAGNA-SITETM tissue expander volume on tomotherapy. Methods: Boluses and MAGNA-SITETM were placed on a Rando phantom to simulate the tissue expander under the pectoralis major. Computed tomography simulation images were transformed through replacing the electron density of (a) metallic artifact region only (Image metallic port) and (b) metallic port and artifact regions (Image Homo). Planning was calculated using fixed-beam and helical-mode techniques. Radiation was delivered with different volumes of the tissue expander. Results: Integrated 997 dose points were calculated. Planning with Image metallic port provided a calculated dose significantly closer to a realistic dose. The percentage of doses achieving the prescribed dose was significantly higher in the helical mode. In layer 2, the 100-mL tissue expander had a significantly lower measurement dose than all other volumes. Volume 150 mL had the highest increase in the measured dose difference from the plan dose at layer 2. Volume 250 mL had the highest percentage of measurement doses passing the 5% dose difference from plan dose. The coldest dose areas were noted in layers 1 and 2, especially in the metallic port-direct image mode. The average dose reduction of the measured cold areas was 6.03 ± 1.94%. Conclusion: Dose distribution was affected by the volume of the metallic port tissue expander. Tomotherapy with proper image heterogeneity correction and helical mode can reduce the attenuation from the metallic port. A tissue expander volume of 150 to 250 mL is suitable. Patients with high risk at the chest wall should be evaluated carefully to avoid underdosing. Radiation oncologists should closely cooperate with plastic surgeons to optimize treatment for each patient.

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PURPOSE: The purpose of this study is to introduce half-beam volumetric-modulated arc therapy (HVMAT), an innovative treatment planning technique from our work, for reducing dose to the organs at risk (OAR) during adjuvant radiotherapy for gynecological cancers. METHODS AND MATERIALS: Seventy-two treatment plans of 36 patients with gynecological cancers receiving adjuvant radiotherapy were assessed. Among them, 36 plans were designed using HVMAT and paired with the other 36 traditional volumetric-modulated arc therapy (VMAT) plans for each patient. The main uniqueness of the HVMAT designs was that it consisted of two opposite-shielded half-beam fields rotated inversely in two coplanar arcs, collocating with the specially-devised avoidance structures to enhance the control of the OAR doses. The dose distributions in HVMAT and VMAT were evaluated and compared using the random effects model. RESULTS: The ratios of OAR doses in HVMAT compared with VMAT showed a comprehensive OAR dose reduction when using HVMAT (V20Gy : bladder, 0.92; rectum, 0.95; V30Gy : bowel, 0.91; femoral heads, 0.66), except for the ilium (V30Gy : 1.12). The overall mean difference for each OAR across V40Gy , V30Gy , V20Gy , and bowel V15Gy was statistically significant (almost all p < 0.001). In addition, HVMAT promoted a better conformity index, homogeneity index, D2% , and V107% of the planning target volume (all p < 0.001). CONCLUSIONS: HVMAT is capable of generating deep double-concave dose distributions with the advantage of reducing dose to several OARs simultaneously. It is highly recommended for pelvic irradiation, especially for treating gynecological cancers in adjuvant radiotherapy.

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Cervical cancer patients may sometimes experience different types of uterine perforation by a tandem during brachytherapy. The purpose of this study was to address possibly different management strategies regarding different tandem positions from a dosimetry aspect by evaluating radiation doses delivered to organs-at-risk (OAR) in order to help medical professionals handle different types of uterine perforation. Images and dosimetry data in cervical cancer brachytherapy with uterine perforation were reviewed. Uterine perforation was classified into anterior and posterior perforation according to their tandem positions. Radiation doses received by OAR, including D2cc and D1cc of the bladder, rectum, and sigmoid colon, were statistically compared with nonperforation. The doses of high-risk clinical target volume (HR-CTV) of cervical tumor and bilateral point A were also compared in order to assure that the plans had not compromised the treatment efficacy. A total of 21 applications were assessed, including 5 with anterior perforation, 4 with posterior perforation, and 12 without perforation. In anterior perforation, the bladder was the only organ that received a significantly increased dose about 30% at D2cc and D1cc. However, in posterior perforation, multiple OAR received significantly excessive doses: approximately 30% for the bladder, 37% for the rectum, and 100% for the sigmoid colon. The OAR dose assessment was based on a statistically equivalent cervical tumor dose. Different management strategies are possible for anterior vs posterior perforation during brachytherapy due to different detrimental extents on OAR dosimetry. The bladder warrants more attention in anterior perforation, without compromising target coverage in treatment planning. On the other hand, repositioning may be considered in posterior perforation due to relatively massive OAR detriments. This concept is a new one and is given for the first time.

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PURPOSE: To introduce the benefits of tangent-based volumetric modulated arc therapy (TVMAT), an innovative radiotherapy planning technique, compared with traditional volumetric modulated arc therapy (VMAT) for advanced left breast cancer needing nodal irradiation. MATERIALS AND METHODS: Twenty-three patients with advanced left breast cancer who had received modified radical mastectomy (MRM) and needed adjuvant radiotherapy including nodal irradiation were assessed. Among 23 radiotherapy treatment plans, 17 plans were designed by using TVMAT technique and 6 plans were designed by using traditional VMAT. The main difference of TVMAT from VMAT was that the area of avoidance sector within specific degrees of angle that had no monitor unit (MU) delivery was used in the arc planning, including a total of 5 sectors in 5 partial arcs. The dosimetries of planning target volume (PTV), right breast, bilateral lungs, and heart between TVMAT and VMAT were compared. RESULTS: The conformity index (CI) and homogeneity index (HI) of PTV between two groups were statistically equivalent (CI: 0.98 ± 0.02 and 0.98 ± 0.03, P = 0.431; HI: 0.12 ± 0.03 and 0.11 ± 0.05, P = 0.177), which indicated that the treatment efficacy of the plans regarding TVMAT was compatible with VMAT. However, all neighboring organs at risk (OAR) showed a great percentage of reduction in mean doses (right breast: 53.1%, right lung: 37.7%, left lung: 8.8%, heart: 21.2%) and low dose parameters (V10: right breast: 72.3%, right lung: 86.1%, left lung: 12.5%, heart: 25.1%; V5: right breast: 56.5%, right lung: 28.3%, left lung: 12.7%, heart: 18.2%) by using TVMAT. CONCLUSION: TVMAT greatly decreases the radiation doses delivered to the OAR with maintained therapeutic efficacy. It is highly recommended for treating breast cancer, especially for difficult cases with left side disease needing nodal irradiation.

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BACKGROUND: Tangent-based intensity modulated radiation therapy (TIMRT) is a common adjuvant radiotherapy strategy for breast cancer patients. This study compared the dosimetric characteristics of tangent-based volumetric modulated arc therapy (TVMAT) and TIMRT for left breast cancer patients during deep inspiration breath-hold (DIBH) and free breathing (FB) techniques. METHODS: Fourteen patients with left breast cancer after breast-conserving surgery were included. The first arc started at 331.8-353.6 degrees and stopped at 281.8-315.0 degrees. The third arc started at 123.2-149.1 degrees and stopped at 88.0-96.0 degrees. The second and fourth arcs were reverse arcs of first and third arcs. DIBH-TIMRT inversing plans were generated using opposing tangential fields. Wilcoxon signed rank test and Spearman correlation were used to examine the significance of dose difference. RESULTS: Compared with FB-TVMAT, the mean heart dose of DIBH-TVMAT plans was reduced from 7.9 Gy to 3.2 Gy (p < 0.001). The average left lung volume receiving 30 Gy or more (V30Gy) was reduced from 12.9 to 5.7% (p < 0.001). DIBH-TVAMT plans resulted in a lower mean dose to the contralateral breast and lung (2 Gy and 0.7 Gy vs 3.4 Gy and 1.5 Gy, respectively) as compared to FB-TVMAT plans. Compared with DIBH-TIMRT, the average left lung V30Gy of DIBH-TVMAT plans was reduced from 8.5 to 5.7% (p = 0.031). As for low-dose areas, exposure of the left lung, right breast, heart and right lung volume with 10 Gy or more was not significantly different between the IMRT- and VMAT-plans. CONCLUSIONS: DIBH-TVMAT for left breast cancer treatment retains treatment plan quality similar to the DIBH-IMRT technique without compromising dose restrictions to the heart, right breast and right lung. DIBH-TVMAT increased left lung protection but still had higher V5Gy to right breast and substantially higher V5Gy to heart. For left breast cancer patients receiving treatment with the DIBH technique, DIBH-TVMAT provides better treatment quality and is a safe and feasible treatment strategy.

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BACKGROUND: To analyze the respiratory-induced motion of each liver segment using helical computed tomography (helical CT) and 4-dimensional computed tomography (4DCT), and to establish the individual segment expansion margin of internal target volume (ITV) to facilitate target delineation of tumors in different liver segments. METHODS: Twenty patients who received radiotherapy with CT-simulation scanning of the whole liver in both helical CT and 10-phase-gated 4DCT were investigated, including 2 patients with esophagus cancer, 4 with lung cancer, 10 with breast cancer, 2 with liver cancer, 1 with thymoma, and 1 with gastric diffuse large B-cell lymphoma (DLBCL). For each patient, 9 representative points were drawn on the helical CT images of liver segments 1, 2, 3, 4a, 4b, 5, 6, 7, and 8, respectively, and adaptively deformed to 2 phases of the 4DCT images at the end of inspiration (phase 0 CT) and expiration (phase 50 CT) in the treatment planning system. Using the amplitude of each point between phase 0 CT and phase 50 CT, we established quantitative data for the respiration-induced motion of each liver segment in 3-dimensional directions. Moreover, using the amplitude between the original helical CT and both 4DCT images, we rendered the individual segment expansion margin of ITV for hepatic target delineation to cover more than 95% of each tumor. RESULTS: The average amplitude (mean ± standard deviation) was 0.6 ± 3.0 mm in the left-right (LR) direction, 2.3 ± 2.4 mm in the anterior-posterior (AP) direction, and 5.7 ± 3.4 mm in the superior-inferior (SI) direction, respectively. All of the segments moved posteriorly and superiorly during expiration. Segment 7 had the largest amplitude in the SI direction, at 8.6 ± 3.4 mm. Otherwise, the segments over the lateral side, including segments 2, 3, 6, and 7, had greater excursion in the SI direction compared to the medial segments. To cover more than 95% of each tumor, the required expansion margin of ITV in the LR, AP, and SI directions were at least 2.5 mm, 2.5 mm, and 5.0 mm on average, respectively, with variations between different segments. CONCLUSIONS: The greatest excursion occurred in liver segment 7, followed by the segments over the lateral side in the SI direction. The individual segment expansion margin of ITV is required to delineate targets for each segment and direction.

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BACKGROUND: This was a retrospective study of patients with human papillomavirus (HPV)-associated oropharyngeal cancer treated with concurrent systemic therapy and radiation. METHODS: Data were extracted through chart review, and statistical analyses included frequency tabulation, chi-square, and Kaplan-Meier tests. RESULTS: Three hundred thirty-nine patients were analyzed; 166 received neoadjuvant chemotherapy. One hundred thirty-six patients were treated with cisplatin, 123 with cetuximab, and 59 with carboplatin. The 2-, 3-, and 5-year actuarial overall survival rates were 92%, 88%, and 78%, respectively. There were no significant differences in survival or disease control when analyzed by systemic agent. Platin-treated patients had greater hematologic toxicity, and required more intravenous hydration. The incidence of confluent mucositis was highest among patients treated with cetuximab. CONCLUSION: Platin and cetuximab seem to have similar efficacy when delivered concurrently with radiation in our retrospective population study. Although platin did cause greater hematologic toxicity, radiation-specific side effects seemed relatively comparable. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1554-E1561, 2016.

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BACKGROUND/PURPOSE: Evidence on the prevention of radiation dermatitis is lacking. The aim of this study was to investigate the effect of 3M Cavilon No Sting Barrier Film and topical corticosteroids on irradiated skin. METHODS: Thirty-nine postoperative breast cancer patients were randomized into three groups for intraindividual comparison (skin to be irradiated was divided into 2 parts): (1) 3M No Sting Barrier Film versus no treatment; (2) corticosteroid versus no treatment; and (3) corticosteroid versus 3M No Sting Barrier Film. The primary end points monitored were the time to first occurrence of grade 1 pruritus, pain score of 3 and grade 2 radiation dermatitis. The secondary end points studied were the incidence of grade 3 radiation dermatitis and total pain scores. Data analysis was done using the SPSS software version 10. RESULTS: Skin given the 3M barrier film experienced a later occurrence of pruritus compared to both corticosteroids and untreated, although this was statistically insignificant. Corticosteroids delayed the time to occurrence of grade 2 dermatitis compared to both untreated skin and 3M barrier film, (mean day of onset = corticosteroid: 52 vs. untreated: 43, p = 0.092; corticosteroid: 53.4 vs. 3M barrier film: 44.5, p = 0.002, t test). Skin given corticosteroids had the lowest incidence of grade 3 dermatitis among all three conditions, although the differences were statistically insignificant. No statistically significant differences were noted in total pain scores. CONCLUSION: The 3M barrier film may be helpful against dermatitis associated pruritus. Corticosteroids may delay the time of onset of severe skin reactions and also reduce the incidence of severe radiation dermatitis.

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