Radiothérapie stéréotaxique extracrânienne et oligométastases

In stage IV cancers, locoregional management of primitive tumours as surgery and/or radiotherapy improved both progression-free survival and overall survival. Among metastatic cancer patients, some of them are considered as oligometastatic stage as they present few metastatic sites associated with low tumor aggressiveness. For those patients, metastatic local control, and therefore prolonged time to progression should be reached through local treatments as surgery and/or radiofrequency ablation and/or stereotactic radiotherapy. Here we propose a review of oligometastatic stage and results from extracranial stereotactic radiotherapy in terms of efficacy and tolerance.     

Effects of ultrasound irradiation on enzymatic hydrolysis of protein and application for the determination of tetracyclines in complex matrices

The widespread use of tetracyclines (TCs) in food animals has led to concerns regarding unsafe residue levels in feed, food and manure. The determination of TCs in such matrices suffers from interference by the interactions between proteins and TCs. Three deproteination methods were compared in this study. In contrast with acid deproteination, which caused a large loss of TCs due to the strong adsorption of TCs on protein precipitates, a normal enzymatic hydrolysis was confirmed to have a merit of effectively releasing TCs from protein matrices, but required treatment time as long as 16 h. The adoption of ultrasound irradiation was proposed to shorten the enzymatic hydrolysis time. After investigating the effects of ultrasound power and irradiation time, the conditions of the ultrasound‐enhanced enzymatic hydrolysis were optimized as ultrasound power of 100 W and irradiation time of 6 min. The ultrasound‐enhanced enzymatic hydrolysis treatment of 6 min yielded recovery of TCs (from protein‐containing matrices) as high as that obtained by the normal enzymatic hydrolysis treatment of 16 h. The acceleration effect of ultrasound irradiation was attributed to ultrasound‐induced cavitation, which increased exposure of both the functional groups of trypsin and the C‐terminal amino acid in the protein that was a cleavage site for trypsin attack. When the ultrasound‐enhanced enzymatic hydrolysis method was used to determine TCs in complex matrices, it was found that this new method achieved recoveries of 89.5, 117.7, 110.4 and 100.0% for oxytetracycline, tetracycline, chlortetracycline and doxycycline, being much higher than those (29.6–39.4%) obtained using the common acid deproteination process. Copyright © 2017 John Wiley & Sons, Ltd.     

TGF-B3 Dependent Modification of Radiosensitivity in Reporter Cells Exposed to Serum From Whole-Body Low Dose-Rate Irradiated Mice

Prior findings in vitro of a TGF-β3 dependent mechanism induced by low dose-rate irradiation and resulting in increased radioresistance and removal of low dose hyper-radiosensitivity (HRS) was tested in an in vivo model. DBA/2 mice were given whole-body irradiation for 1 h at low dose-rates (LDR) of 0.3 or 0.03 Gy/h. Serum was harvested and added to RPMI (4% mouse serum and 6% bovine serum).This medium was transferred to reporter cells (T-47D breast cancer cells or T98G glioblastoma cells). The response to subsequent challenge irradiation of the reporter cells was measured by the colony assay. While serum from unirradiated control mice had no effect on the radiosensitivity in the reporter cells, serum from mice given 0.3 Gy/h or 0.03 Gy/h for 1 h removed HRS and also increased survival in response to doses up to 5 Gy. The effect lasted for at least 15 months after irradiation. TGF-β3 neutralizer added to the medium containing mouse serum inhibited the effect. Serum from mice given irradiation of 0.3 Gy/h for 1 h and subsequently treated with iNOS inhibitor 1400W did not affect radiosensitivity in reporter cells; neither did serum from the unirradiated progeny of mice given 1h LDR whole-body irradiation.     

Accelerated partial breast irradiation with interstitial multicatheter brachytherapy after breast-conserving surgery for low-risk early breast cancer

Patients with low-risk invasive ductal carcinoma treated with breast-conserving surgery (BCS) were included in a multicatheter brachytherapy APBI protocol. The primary endpoint was ipsilateral breast recurrence. Between December 2008–December 2017, 186 low-risk breast cancer patients were treated with APBI using interstitial multicatheter brachytherapy and followed prospectively. At 5-years of follow-up, cumulative local recurrence (LR) and cause-specific survival was 1.1% (95% CI 0.3–1.9) and 98.3% (95% CI 97.3–99.3%) respectively. No grade 3 adverse effects were observed. Postoperative APBI using multicatheter brachytherapy after BCS in early breast cancer patients have excellent rates of local control and survival, without significant toxicity.     

Prophylactic Cranial Irradiation for Limited-Stage Small-Cell Lung Cancer Patients: Secondary Findings From the Prospective Randomized Phase 3 CONVERT Trial

Introduction

The impact of the dose and fractionation of thoracic radiotherapy on the risk of developing brain metastasis (BM) has not been evaluated prospectively in limited stage SCLC patients receiving prophylactic cerebral irradiation (PCI).

A transendocardial delivery and intracardiac ultrasound irradiation treatment catheter

Abstract

Objectives: This study introduces the structural design, working principles, performance testing and treatment effects of a newly developed ultrasonic irradiation delivery and treatment catheter system that integrates interventional catheterization technology.

Background: Systemic administration method needs a high dose of gene and induces side effect of non-target organ delivery. Direct intramyocardial injection of a low-dose angiogenic gene followed by insonation treatment can enhance gene expression. So, a novel transendocardial gene delivery and intracardiac ultrasound irradiation strategy was tested.

Methods: The medical interventional ultrasonic therapeutic apparatus is comprised of an ultrasonic irradiation catheter and a host. The ultrasonic irradiation catheter, which is equipped with an advance-and-retreat convenient miniature syringe needle and a miniature piezoelectric transducer on the tip, was used. Twelve dogs were divided into three groups: (1) EGFP and US (EGFP?+?US), (2) EGFP alone and (3) control group. In the EGFP?+?US group, EGFP plasmid DNA (500?µg) was injected and followed by intracardiac insonation. In the EGFP alone group, EGFP plasmid DNA (500?µg) was injected without insonation. In the control group, saline was injected.

Results: The catheter can enter the heart through percutaneous intervention to realize intramyocardial injection, directly irradiate cardiac muscular tissues at close range and correctly control the ultrasonic irradiation energy delivered to cardiac muscular tissues. Compared with the EGFP gene group, an average sixfold enhancement in gene expression was achieved in the EGFP EGFP?+?US group (p?<?0.05).

Conclusions: The experimental results confirmed that the treatment catheter was safe and reliable, which can realize transendocardial intramyocardial gene injection in the left ventricular chamber, and the ultrasonic parameter can increase gene expression after intracardiac ultrasonic irradiation. The intracardiac ultrasound irradiation treatment catheter may be a useful delivery and therapy tool in the future.     

Radiothérapie en conditions stéréotaxiques des tumeurs bronchopulmonaires

Stereotactic radiotherapy for lung cancer is a technique that is now well established in the therapeutic arsenal. Protocols are effective, with very high local control rate and an acceptable rate of survival if one takes into account the patient's age and comorbidities. Complications are rare. This review of the literature analyses the whole process of the therapeutic indications and future prospects.