Brachytherapy: An emblematic example of extreme hypofractionated regimen

In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.     

Sofosbuvir-velpatasvir en pacientes mexicanos con hepatitis C: una revisión retrospectiva

IntroductionThe sofosbuvir-velpatasvir (SOF/VEL) combination is a direct-acting antiviral therapy that is authorized and available in Mexico, making the performance of a real-world multicenter study that evaluates the sustained virologic response at 12 weeks post-treatment a relevant undertaking.MethodsA retrospective review of the case records of 241 patients seen at 20 hospitals in Mexico was conducted to assess hepatitis C treatment with the SOF/VEL combination (n = 231) and the sofosbuvir/velpatasvir/ribavirin (SOF/VEL/RBV) combination (n = 10). The primary efficacy endpoint was the percentage of patients that achieved SVR at 12 weeks after the end of treatment.ResultsOverall SVR was 98.8% (95% CI 97.35-100%). Only three patients did not achieve SVR, two of whom had cirrhosis and a history of previous treatment with peg-IFN. Of the subgroups analyzed, all the patients with HIV coinfection, three patients with genotype 3, and the patients treated with the SOF/VEL/RBV combination achieved SVR. The subgroups with the lower success rates were patients that were treatment-experienced (96.8%) and patients with F1 fibrosis (95.5%). The most frequent adverse events were fatigue, headache, and insomnia. No serious adverse events were reported.ConclusionTreatments with SOF/VEL and SOF/VEL/RBV were highly safe and effective, results coinciding with those of other international real-world studies.     

右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响

目的 探讨右美托咪定联合综合体温保护对腔镜手术治疗老年恶性肿瘤患者苏醒期质量及免疫功能的影响。方法 选择择期行腔镜手术治疗的老年恶性肿瘤患者90例，随机均分为3组：对照组（C组）、体温保护组（T组）和体温保护联合右美托咪定组（T-D组），每组30例。C组常规体温保护，T组和T-D组综合体温保护；T-D组麻醉诱导前10 min泵注右美托咪定0.5 μg/kg。记录3组患者麻醉诱导开始时（T₀）、手术开始30 min（T₁）、60 min（T₂）、90 min（T₃）、120 min（T₄）以及手术结束时（T₅）的鼻咽温度；于T₀、术后2 h（T₆）、24 h（T₇）和48 h（T₈）时抽取静脉血标本，测定T淋巴细胞亚群（CD3⁺、CD4⁺和CD8⁺）和自然杀伤细胞（NK cell）水平；记录患者术中麻醉药物用量及苏醒期质量指标。结果 与T₀比较，C组T₂～T₅时点鼻咽温度均明显降低（P < 0.05）；与C组比较，T组和T-D组T₂～T₅时点鼻咽温度明显升高（P < 0.05）。与T₀时点比较，C组、T组和T-D组T₆、T₇和T₈时点CD3⁺和NK cell活性均明显降低（P < 0.05）；C组在T₆、T₇和T₈时点，T组和T-D组在T₆和T₇时点，CD4⁺活性均明显降低（P < 0.05）。与C组比较，T组和T-D组T₆和T₇时点CD3⁺细胞活性均明显升高（P < 0.05）；T组在T₇时点，T-D组在T₆和T₇时点，CD4⁺细胞活性均明显升高（P < 0.05）；T组在T₇时点，T-D组在T₆、T₇和T₈时点，NK cell活性均明显升高（P < 0.05）。结论 采用体温保护措施联合右美托咪定能够维持老年恶性肿瘤患者的体温稳定，减少围手术期意外低体温（IPH）的发生，并有效提高患者苏醒期质量，减轻免疫抑制程度，加速患者早期恢复。     

Magnetron Sputtered CsPbCl3 Perovskite Detectors as Real-Time Dosimeters for Clinical Radiotherapy

The aim of this study is to investigate the feasibility of manufacturing thin real-time relative dosimeters for clinical radiotherapy (RT) with potential applications for transmission monitoring in vivo dosimetry and pre-treatment dose verifications. Thin (≈1 μm) layers of a high sensitivity, wide bandgap semiconductor, the inorganic perovskite CsPbCl₃, have been grown for the first time by magnetron sputtering on plastic substrates equipped with electrode arrays. Prototype devices have been tested in real-time configuration to evaluate the dose delivered by a 6 MV photon beam from a linear accelerator. Linearity of the charge with the dose has been verified over three order of magnitudes, linearity of the current signal with the dose rate has been also successfully tested in the range 0.5-4.3 Gy/min. The combination of high sensitivity per unit volume and wide bandgap provides high signal-to-noise ratios, up to 70, even at moderate applied voltages. The Schottky diode configuration allows the detector to operate without bias voltage (null bias).The blocking-barrier structure allows to confine the active volume within sub-millimetric sizes, a quite attractive feature in view to increase granularity and achieve the high spatial resolutions required in modern RT techniques. All the above-mentioned features indeed pave the way to a novel generation of flexible, transmission, real time dosimeters for clinical radiotherapy.     

Improving Lesbian,Gay, Bisexual,Transgender, Queer and Two-Spirit Content in a Radiation Therapy Undergraduate Curriculum

Lesbian, gay, bisexual, transgender, queer and two-spirit plus (LGBTQ2S+) people have distinct healthcare needs that may be unaddressed in many undergraduate healthcare curricula. The Radiation Therapy Program (RADTH) at the University of Alberta underwent a review of the three-year didactic curriculum using an online survey. The survey sought to ascertain if, where and how topics related to LGBTQ2S + healthcare are taught. Results indicated that out of 10 RADTH program faculty respondents, three teach related topics. The total time dedicated within the three-year curriculum was approximately three and a half hours. Other findings showed that faculty are interested in receiving more education in this area and would favour discussions about how to incorporate these themes into appropriate courses. This preliminary investigation demonstrated that there has been some initial work in this area, but there is more to be done.     

Protective activities of ellagic acid and urolithins against kidney toxicity of environmental pollutants: A review

Oxidative stress and inflammation are two possible mechanisms related to nephrotoxicity caused by environmental pollutants. Ellagic acid, a powerful antioxidant phytochemical, may have great relevance in mitigating pollutant-induced nephrotoxicity and preventing the progression of kidney disease. This review discusses the latest findings on the protective effects of ellagic acid, its metabolic derivatives, the urolithins, against kidney toxicity caused by heavy metals, pesticides, mycotoxins, and organic air pollutants. We describe the chelating, antioxidant, anti-inflammatory, antifibrotic, antiautophagic, and antiapoptotic properties of ellagic acid to attenuate nephrotoxicity. Furthermore, we present the molecular targets and signaling pathways that are regulated by these antioxidants, and suggest some others that should be explored. Nevertheless, the number of reports is still limited to establish the efficacy of ellagic acid against kidney damage induced by environmental pollutants. Therefore, additional preclinical studies on this topic are required, as well as the development of well-designed clinical trials.     

Hypofractionated radiation therapy for invasive breast cancer: From moderate to extreme protocols

Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria.