MiR-663a Inhibits Radiation-Induced Epithelium-to-Mesenchymal Transition by Targeting TGF-β1

Objective miR-663 a has been reported to be downregulated by X-ray irradiation and participates in radiation-induced bystander effect via TGF-β1. The goal of this study was to explore the role of mi R-663 a during radiation-induced Epithelium-to-mesenchymal transition(EMT).Methods TGF-β1 or IR was used to induce EMT. After mi R-663 a transfection, cell migration and cell morphological changes were detected and the expression levels of mi R-663 a, TGF-β1, and EMT-related factors were quantified.R...     

优化扫描范围对CT冠状动脉成像辐射剂量和图像质量的影响

目的 初步探讨优化扫描范围(FOV)对冠状动脉CT成像(CTA)辐射剂量和图像质量的影响.方法 选取100例临床疑似冠心病的患者进行冠状动脉CTA检查,随机分成A、B两组,每组各50例.A组FOV为气管分叉处至心脏下缘1 cm;B组FOV根据平扫图像确定,即冠状动脉树上缘1 cm至心尖部心包即将消失的层面.记录患者增强扫描的剂量长度乘积(DLP),选择冠状动脉不同节段测量其对比剂增强水平.分析A、B两组的FOV、有效辐射剂量(ED)及图像质量有无统计学差异.结果 两组患者平均年龄、性别、体重指数(BMI)比较均无统计学意义;A组平均FOV、ED分别为(15.31±1.51)cm、(15.10±2.00) mSv,均高于B组的(13.51±1.68)cm、(12.02±1.40)mSv,且差异均有统计学意义(P＜0.05).两组共显示冠状动脉1303个节段,A组669个节段,B组634个节段,两组间比较差异无统计学意义(P＞0.05).右冠状动脉(RCA)近段、左冠状动脉前降支(LAD)近段及左回旋支(LCX)近段CT值水平差异无统计学意义.结论 根据平扫图像优化冠状动脉CTA FOV,既能有效降低辐射剂量,同时又能保证图像质量,为临床诊断冠心病提供参考信息.     

Implementation of Constant Dose Rate and Constant Angular Spacing Intensity-modulated Arc Therapy for Cervical Cancer by Using a Conventional Linear Accelerator

Background:

Volumetric-modulated arc therapy (VMAT) can only be implemented on the new generation linacs such as the Varian Trilogy^® and Elekta Synergy^®. This prevents most existing linacs from delivering VMAT. The purpose of this study was to investigate the feasibility of using a conventional linear accelerator delivering constant dose rate and constant angular spacing intensity-modulated arc therapy (CDR-CAS-IMAT) for treating cervical cancer.

Methods:

Twenty patients with cervical cancer previously treated with intensity-modulated radiation therapy (IMRT) using Varian Clinical 23EX were retreated using CDR-CAS-IMAT. The planning target volume (PTV) was set as 50.4 Gy in 28 fractions. Plans were evaluated based on the ability to meet the dose volume histogram. The homogeneity index (HI), target volume conformity index (CI), the dose to organs at risk, radiation delivery time, and monitor units (MUs) were also compared. The paired t-test was used to analyze the two data sets. All statistical analyses were performed using SPSS 19.0 software.

Results:

Compared to the IMRT group, the CDR-CAS-IMAT group showed better PTV CI (0.85 ± 0.03 vs. 0.81 ± 0.03, P = 0.001), clinical target volume CI (0.46 ± 0.05 vs. 0.43 ± 0.05, P = 0.001), HI (0.09±0.02 vs. 0.11 ± 0.02, P = 0.005) and D95 (5196.33 ± 28.24 cGy vs. 5162.63 ± 31.12 cGy, P = 0.000), and cord D2 (3743.8 ± 118.7 cGy vs. 3806.2 ± 98.7 cGy, P = 0.017) and rectum V40 (41.9 ± 6.1% vs. 44.2 ± 4.8%, P = 0.026). Treatment time (422.7 ± 46.7 s vs. 84.6 ± 7.8 s, P = 0.000) and the total plan Mus (927.4 ± 79.1 vs. 787.5 ± 78.5, P = 0.000) decreased by a factor of 0.8 and 0.15, respectively. The IMRT group plans were superior to the CDR-CAS-IMAT group plans considering decreasing bladder V50 (17.4 ± 4.5% vs. 16.6 ± 4.2%, P = 0.049), bowel V30 (39.6 ± 6.5% vs. 36.6 ± 7.5%, P = 0.008), and low-dose irradiation volume; there were no significant differences in other statistical indexes.

Conclusions:

Patients with cervical cancer treated with CDR-CAS-IMAT using Varian Clinical 23EX can get equivalent or superior dose distribution compared to those treated with IMRT. CDR-CAS-IMAT has a less treatment time and MU, which can reduce the uncertainty factor and patient discomfort in treatment.     

The risks of radiation therapy and lymphedema in shoulder surgery

BackgroundRadiation therapy has proven efficacy for cancer treatment but is not without short- and long-term side effects, including radiation-induced lymphedema. There has been limited evidence on the secondary effects of prior radiation therapy on shoulder surgery. The purpose of this study is to evaluate the short-term outcomes of shoulder arthroplasty and rotator cuff repair (RCR) in patients who have undergone ipsilateral radiation therapy and/or have preoperative upper extremity lymphedema.MethodsDuke Enterprise Data Unified Content Explorer was used to query for patients who underwent RCR at our institution. Patients with radiation therapy for breast or lung cancer prior to ipsilateral RCR or shoulder arthroplasty were included. Patients with less than 2 years of follow-up were excluded. Data variables included primary tumor type, dates of cancer diagnoses, radiation treatment, axillary lymph node dissection (aLND), presence of lymphedema, index shoulder operations, most recent follow-up, and surgical and medical complications within the 90-day postoperative period. Additional oncologic variables included total Gray (Gy) delivered.ResultsTwenty-one patients underwent radiation therapy and subsequent shoulder arthroplasty or RCR (13 RCR, 3 total shoulder arthroplasty, 5 reverse shoulder arthroplasty). There were 20 females and 1 male with an average age of 65.6 years (47-82) and average clinical follow-up of 4.4 years (2.0-7.4). Oncologic diagnoses included lung (4.8%) and breast (95.2%) cancer. Average radiation dose delivered was 53.3 Gy (38.5-64) in the cohort. The average time from last external beam radiation therapy to shoulder surgery was 4.3 years (0.3-18.0). One of 13 (7.7%) 90-day postoperative complications was reported in the RCR cohort: a superficial vein thrombosis. One of 8 (12.5%) 90-day complications was reported in the arthroplasty cohort: a clinically suspected but radiographically absent acromial stress fracture in a reverse shoulder arthroplasty that did not require operative intervention. Overall, there were no revisions, reoperations, or shoulder-related unplanned inpatient 90-day readmissions. Among 10 patients with prior aLND, 3 (30%) (2 RCR, 1 arthroplasty) experienced new or worsening upper extremity lymphedema within the immediate postoperative period.ConclusionA minority of patients having undergone prior radiation therapy and aLND who subsequently underwent ipsilateral shoulder surgery experienced worsening subjective upper extremity lymphedema. Although 10% of these radiation therapy patients experienced minor complications within 90 days of their shoulder surgery, none were severe enough to merit inpatient admission or revision surgery.     

Radiation‐induced nausea and vomiting in head and neck cancer: Is it something worth considering in the intensity modulated radiotherapy era? “A narrative review”

Radiation therapy is one of the cornerstones in the treatment of head and neck squamous cell carcinomas (HNSCC), alone or in combination with chemotherapy or surgery. Technological advances which occurred over the last few decades have increased the efficacy of radiotherapy (RT), particularly, intensity‐modulated RT (IMRT). IMRT can deliver treatments on complex tumoral targets with dose escalation while sparing organs at risk; anyway IMRT deposits dose in unpredictable patterns outside of the target volume with the purpose of improving conformality. Radiation‐induced nausea and vomiting (RINV) is a frequent albeit neglected side effect of RT that can lead to delays in treatment with serious consequences on cure rates. According to several guidelines (MASCC 2016, NCCN 2018), RT for HNSCC has traditionally been regarded as a low emetic risk treatment. Nevertheless, several works suggest that IMRT could increase RINV. Further studies are needed to define the exact incidence and the detailed pathophysiology of RINV in patients with HNSCC treated with state of art IMRT techniques, with and without concurrent chemotherapy.     

Management decisions for adolescent idiopathic scoliosis significantly affect patient radiation exposure

Background contextAdolescent idiopathic scoliosis (AIS) patients treated before the 1990s have a 1% to 2% increased lifetime risk of developing breast and thyroid cancer as a result of ionizing radiation from plain radiographs. Although present plain radiographic techniques have been able to reduce some of the radiation exposure, modern treatment algorithms for scoliosis often include computed tomography (CT) and intraoperative fluoroscopy. The exact magnitude of exposure to ionizing radiation in adolescents during modern scoliosis treatment is therefore unclear.PurposeTo determine the difference in radiation exposures in patients undergoing various forms of treatment for AIS.Study designRetrospective cohort.Patient samplePatients aged 9 to 18 years with a diagnosis of AIS, followed and/or treated with nonoperative or operative management for a minimum of 2 years.Outcome measuresNumber of radiographs and total radiation exposure calculated.MethodsThe charts and radiographs of patients managed for AIS at a single institution between September 2007 and January 2012 were reviewed. Patients were divided into three groups: operative group, braced group, and observation group. Patient demographics, Cobb angles, and curve types were recorded. The number of radiographs per year that each patient received and the total radiation dose were recorded. The plain radiographic radiation exposure was then combined with the direct exposure recording from ancillary tests, such as fluoroscopy and CT, and a radiation exposure rate was calculated (mrad/y). A single-factor analysis of variance (α=0.01) with a Tukey honest significant difference post hoc analysis was used to test significance between groups.ResultsTwo hundred sixty-seven patients were evaluated: 86 operative, 80 brace, and 101 observation. All groups had similar demographics and curve type distribution. The mean initial Cobb angle at presentation was significantly different between the groups: operative (57°±11°), brace (24°±7.9°), and observation (18°±9.4°) (p<.01). There was a significant difference among the groups in terms of the mean number of radiographs received per year; operative group, 12.2 (95% confidence interval [CI]: 10.8–13.5; p<.001); braced group, 5.7 (95% CI: 5.2–6.2; p<.001), and observed group, 3.5 (95% CI: 3.160–3.864; p<.001). The operative group received 1,400 mrad per year (95% CI: 1,350–1,844; p<.001), braced group received 700 mrad per year (95% CI: 598–716; p<.001), and observed group received 400 mrad per year (95% CI: 363–444; p<.001). Importantly, 78% of radiation in the operative group was attributable to the operative fluoroscopy exposure.ConclusionsSignificant differences exist in the total radiation exposure in scoliosis patients with different treatment regimens, with operative patients receiving approximately 8 to 14 times more radiation than braced patients or those undergoing observation alone, respectively. Operative patients also receive more than twice the radiation per year than braced or observed patients. Almost 78% of the annual radiation exposure for operative patients occurs intraoperatively. Because children are notably more sensitive to the carcinogenic effects of ionizing radiation, judicious use of present imaging methods and a search for newer imaging methods with limited ionizing radiation should be undertaken.