Tumor ablation with nanosecond pulsed electric fields

Liver cancer is one of the most malignant cancers. It is reported that 600 000 patients died from liver cancer every year. [1,2] Hepatocellular carcinoma (HCC) is a particular problem because symptoms are not evident until the disease has progressed and hepatitis B, which is prominent specific regions of Asia, is a common precursor of the disease. There are many liver cancer

Percutaneous local tumor ablation vs. stereotactic body radiotherapy for early-stage non-small cell lung cancer: a systematic review and meta-analysis

Background:Percutaneous local tumor ablation(LTA)and stereotactic body radiotherapy(SBRT)have been regarded as viable treatments for early-stage lung cancer patients.The purpose of this study was to compare the efficacy and safety of LTA with SBRT for early-stage non-small cell lung cancer(NSCLC).Methods:PubMed,Embase,Cochrane library,Ovid,Google scholar,CNKI,and CBMdisc were searched to identify potential eligible studies comparing the efficacy and safety of LTA with SBRT for early-stage NSCLC published between January 1,1991,and May 31,2021.Hazard ratios(HRs)or odds ratios(ORs)with 95%confidence intervals(CIs)were applied to estimate the effect size for overall survival(OS),progression-free survival(PFS),locoregional progression(LP),and adverse events.Results:Five studies with 22,231 patients were enrolled,including 1443 patients in the LTA group and 20,788 patients in the SBRT group.The results showed that SBRT was not superior to LTA for OS(HR=1.03,95%CI:0.87-1.22,P=0.71).Similar results were observed for PFS(HR=1.09,95%CI:0.71-1.67,P=0.71)and LP(HR=0.66,95%CI:0.25-1.77,P=0.70).Subgroup analysis showed that the pooled HR for OS favored SBRT in patients with tumors sized>2 cm(HR=1.32,95%CI:1.14-1.53,P=0.0003),whereas there was no significant difference in patients with tumors sized≤2 cm(HR=0.93,95%CI:0.64-1.35,P=0.70).Moreover,no significant differences were observed for the incidence of severe adverse events(≥grade 3)(OR=1.95,95%CI:0.63-6.07,P=0.25)between the LTA group and SBRT group.Conclusions:Compared with SBRT,LTA appears to have similar OS,PFS,and LP.However,for tumors>2 cm,SBRT is superior to LTA in OS.Prospective randomized controlled trials are required to determine such findings.

Intrinsic elastic conductors with internal buckled electron pathway for flexible electromagnetic interference shielding and tumor ablation

The elastic conductor is crucial in wearable electronics and soft robotics.The ideal intrinsic elastic bulk conductors show uniform three-dimensional conductive networks and stable resistance during large stretch.A challenge is that the variation of resistance is high under deformation due to disconnection of conductive pathway for bulk elastic conductors.Our strategy is to introduce buckled structure into the conductive network,by self-assembly of a carbon nanotube layer on the interconnecting micropore surface of a prestrained foam,followed by strain relaxation.Both unfolding of buckles and flattening of micropores contributed to the stability of the resistance under deformation(2.0%resistance variation under 70%strain).Microstructural analysis and finite element analysis illustrated different patterns of two-dimensional buckling structures could be obtained due to the imperfections in the conductive layer.Applications as all-directional interconnects,stretchable electromagnetic interference shielding and electrothermal tumor ablation were demonstrated.

Safety trial of high-intensity focused ultrasound therapy for pancreatic cancer

AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.

An Overview of CyberKnife Radiosurgery

Stereotactic radiosurgery is a non-invasive procedure that utilizes precisely targeted radiation as an ablative surgical tool. Conventional radiosurgery devices, such as the Gamma Knife, rely upon skeletally attached Stereotactic frames to immobilize the patient and precisely determine the 3D spatial position of a tumor. A relatively new instrument, the CyberKnife (Accuray, Inc., Sunnyvale, CA), makes it possible to administer radiosurgery without a frame. The CyberKnife localizes clinical targets using a very accurate image-to-image correlation algorithm, and precisely cross-fires high-energy radiation from a lightweight linear accelerator by means of a highly manipulable robotic arm. CyberKnife radiosurgery is an effective alternative to conventional surgery or radiation therapy for a range of tumors and some non-neoplastic disorders. This report will describe CyberKnife technology and oncologic applications in neurosurgery and throughout the body.

Self-monitored Nd-doped MoSe_(2) nanosheets with near-infrared luminescent sensing for photothermal therapy

The acquisition of real-time temperature monitoring during photothermal therapy is significant to prevent unnecessary damage to healthy tissues.However,owing to complexity and diverse factors in microenvironment of cells,there still remain considerable challenges in achieving noninvasive temperature measurement and manipulation in therapeutic process.Herein,biocompatible Nd-doped MoSe_(2) nanosheets have been developed on the premise of excellent photothermal effect,which manifest desirable photoluminescence and distinct temperature self-monitored capability in near-infrared Ⅰ and Ⅱ bio-windows.Based on thermally coupled energy levels of Nd ions,the real-time monitoring on temperature changes in intracellular environment can be realized which provide instant temperature feedbacks to avoid side effects from hyperthermia.Exclusive of detrimental elements such as F and Pb,the objective nanosheets manifest satisfactory biosafety and can induce effective tumor ablation under near-infrared irradiation with photothermal conversion efficiency up to 40.8%,providing an innovative vision for developing more precisely and safely photothermal approaches.

Photothermal scaffolds/surfaces for regulation of cell behaviors

Regulation of cell behaviors and even cell fates is of great significance in diverse biomedical applications such as cancer treatment,cell-based therapy,and tissue engineering.During the past decades,diverse methods have been developed to regulate cell behaviors such as applying external stimuli,delivering exogenous molecules into cell interior and changing the physicochemical properties of the substrates where cells adhere.Photothermal scaffolds/surfaces refer to a kind of materials embedded or coated with photothermal agents that can absorb light with proper wavelength(usually in near infrared region)and convert light energy to heat;the generated heat shows great potential for regulation of cell behaviors in different ways.In the current review,we summarize the recent research progress,especially over the past decade,of using photothermal scaffolds/surfaces to regulate cell behaviors,which could be further categorized into three types:(i)killing the tumor cells via hyperthermia or thermal ablation,(ii)engineering cells by intracellular delivery of exogenous molecules via photothermal poration of cell membranes,and(iii)releasing a single cell or an intact cell sheet via modulation of surface physicochemical properties in response to heat.In the end,challenges and perspectives in these areas are commented.