Unraveling the efficacy network: A network meta-analysis of adjuvant external beam radiation therapy methods after hepatectomy

BACKGROUND Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis.Postoperative adjuvant external radiation therapy(RT)has been shown to effectively prevent recurrence after liver cancer resection.However,there are multiple RT techniques available,and the differ-ential effects of these techniques in preventing postoperative liver cancer re-currence require further investigation.AIM To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival(OS)and disease-free survival(DFS)and to determine the optimal strategy.METHODS This study involved network meta-analyses and followed the PRISMA guidelines.The data of qualified studies published before July 10,2023,were collected from PubMed,Embase,the Web of Science,and the Cochrane Library.We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints.The magnitudes of the effects were determined using risk ratios with 95%confidential intervals.The results were analyzed using R software and STATA software.RESULTS A total of 12 studies,including 1265 patients with hepatocellular carcinoma(HCC)after liver resection,were included in this study.There was no significant heterogeneity in the direct paired comparisons,and there were no significant differences in the inclusion or exclusion criteria,intervention measures,or outcome indicators,meeting the assumptions of heterogeneity and transitivity.OS analysis revealed that patients who underwent stereotactic body radiotherapy(SBRT)after resection had longer OS than those who underwent intensity modulated radiotherapy(IMRT)or 3-dimensional conformal RT(3D-CRT).DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS.Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT.CONCLUSION HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT.IMRT,a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT,may be a preferred option.

Outcomes of External-Beam Radiation Therapy Boost with Conventional Fractionation in Cervical Cancer: A Retrospective Analysis about 133 Cases

Introduction: External-beam radiation therapy boost is a treatment option in cervical cancer when brachytherapy is not feasible. Though less effective than brachytherapy, some encouraging results have been reported from some institutions experiences. We conducted this study to assess outcomes of EBRT boost for our patients at National Institute of Oncology in Rabat. Patients and Methods: We collected data from patients treated for cervical cancer between January 2012 and December 2015. Patients, tumor and treatment characteristics were collected. Overall survival (OS), disease-free survival (DFS) and prognostic factors influencing DFS were assessed. Results: One hundred and thirty-three patients were enrolled. Median age was 52 years. Patient haemoglobin level ranged from 3.9 to 15.5 g/dl [mean: 11.2 g/dl]. Most tumors were classified stage III/IVA (63.2%) according to the FIGO classification. Regional lymph node metastases (pelvic and or para-aortic) were observed in 45.1%. Median total dose to tumor was 69.6 Gy (ranging from 66 to 70 Gy). Overall treatment time was protracted, with a median of 60 days. Most of patients received concurrent chemotherapy (94.7%) and the number of cycle ranged from 2 to 7 (median = 5). The follow-up median was 31.3 months, ranging from 6.2 to 96.8 months. At the first visit, most patients achieved complete response (80.5%). Five years OS and DFS were 47% and 44% respectively. In univariate and multivariate analysis, regional lymph nodes metastasis (presence or absence) and haemoglobin level (≤11 g/dl and >11 g/dl) were the two significant and independent prognostic factors influencing DFS (HR: 1.86;p = 0.01 for the former) (HR: 0.59;p = 0.03 for the latter). Conclusion: Our study showed that EBRT boost in conventional fractionation was an acceptable treatment option for cervical cancer unamenable to brachytherapy, especially in the two subgroups of patients that are those without pelvic and/or para-aortic lymph node metastasis and those with haemoglobin level above 11 g/dl.

Quantitative determination of the electron beam radiation dose for SARS-CoV-2 inactivation to decontaminate frozen food packaging

The spread of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) from cold-chain foods to frontline workers poses a serious public health threat during the current global pandemic. There is an urgent need to design concise approaches for effective virus inactivation under different physicochemical conditions to reduce the risk of contagion through viral contaminated surfaces of cold-chain foods. By employing a time course of electron beam exposure to a high titer of SARS-CoV-2 at cold-chain temperatures, a radiation dose of 2 kGy was demonstrated to reduce the viral titer from 10^(4.5)to 0 median tissue culture infectious dose(TCID_(50))/mL. Next,using human coronavirus OC43(HCoV-OC43) as a suitable SARS-CoV-2 surrogate, 3 kGy of high-energy electron radiation was defined as the inactivation dose for a titer reduction of more than 4 log units on tested packaging materials. Furthermore, quantitative reverse transcription PCR(RT-qPCR) was used to test three viral genes,namely, E, N, and ORF1ab. There was a strong correlation between TCID50and RT-qPCR for SARS-CoV-2detection. However, RT-qPCR could not differentiate between the infectivity of the radiation-inactivated and nonirradiated control viruses. As the defined radiation dose for effective viral inactivation fell far below the upper safe dose limit for food processing, our results provide a basis for designing radiation-based approaches for the decontamination of SARS-CoV-2 in frozen food products. We further demonstrate that cell-based virus assays are essential to evaluate the SARS-CoV-2 inactivation efficiency for the decontaminating strategies.

Selective linear etching of monolayer black phosphorus using electron beams

Point and line defects are of vital importance to the physical and chemical properties of certain two-dimensional(2D)materials.Although electron beams have been demonstrated to be capable of creating single-and multi-atom defects in 2D materials,the products are often random and difficult to predict without theoretical inputs.In this study,the thermal motion of atoms and electron incident angle were additionally considered to study the vacancy evolution in a black phosphorus(BP)monolayer by using an improved first-principles molecular dynamics method.The P atoms in monolayer BP tend to be struck away one by one under an electron beam within the displacement threshold energy range of 8.55-8.79 eV,which ultimately induces the formation of a zigzag-like chain vacancy.The chain vacancy is a thermodynamically metastable state and is difficult to obtain by conventional synthesis methods because the vacancy formation energy of 0.79 eV/edge atom is higher than the typical energy in monolayer BP.Covalent-like quasi-bonds and a charge density wave are formed along the chain vacancy,exhibiting rich electronic properties.This work proposes a theoretical protocol for simulating a complete elastic collision process of electron beams with 2D layers and will facilitate the establishment of detailed theoretical guidelines for experiments on 2D material etching using focused high-energy electron beams.

Improving patient care and accuracy of given doses in radiation therapy using in vivo dosimetry verification

Objective This work aims to verify and improve the dose given for cancer patients in radiation therapy by using diodes to enhance patient in vivo dosimetry on a routine basis. Some characteristics of two available semi-conductor diode dosimetry systems were evaluated. Methods The diodes had been calibrated to read the dose at Dmax below the surface. Correction factors of clinical relevance were quantified to convert the diode readings into patient dose. The diode was irradiated at various gantry angles （increments of 45~）, various Field Sizes and various Source to Surface Distances （SSDs）. Results The maximal response variation in the angular response with respect to an arbitrary angle of 0~ was 1.9%, and the minimum variation was 0.5%. The response of the diode with respect to various field siz- es showed the minimum and the maximum variations in the measured dose from the diode; the calculated doses were -1.6% （for 5 cm x 5 cm field size） and 6.6% （for 40 cm x 40 cm field size）. The diode exhibited a significant perturbation in the response, which decreased with increasing SSD. No discrepancies larger than 5% were detected between the expected dose and the measured dose. Conclusion The results indicate that the diodes exhibit excellent linearity, dose reproducibility and minimal anisotropy; that they can be used with confidence for patient dose verification. Furthermore, diodes render real time verification of the dose delivered to patients.

Application of Statistical Process Control for Setting Action Thresholds as Quality Assurance of Dose Verifications in External Beam Radiotherapy

Purpose: To test the concept of Statistical Process Control (SPC) as a Quality Assurance (QA) procedure for dose verifications in external beam radiation therapy in conventional and 3D Conformal Radiotherapy (3D-CRT) treatment of cervical cancer. Materials and Methods: A study of QA verification of target doses of 198 cervical cancer patients undergoing External Beam Radiotherapy (EBRT) treatments at two different cancer treatment centers in Kenya was conducted. The target doses were determined from measured entrance doses by the diode in vivo dosimetry. Process Behavior Charts (PBC) developed by SPC were applied for setting Action Thresholds (AT) on the target doses. The AT set was then proposed as QA limits for acceptance or rejection of verified target doses overtime of the EBRT process. Result and Discussion: Target doses for the 198 patients were calculated and SPC applied to test whether the action limits set by the Process Behavior Charts could be applied as QA for verified doses in EBRT. Results for the two sub-groups of n = 3 and n = 4 that were tested produced action thresholds which are within clinical dose specifications for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. Conclusion: Action thresholds set by SPC were within the clinical dose specification of ±5% uncertainty for both conventional AP/PA and 3D-CRT EBRT treatment techniques for cervical cancer. So the concept of SPC could be applied in setting QA action limits for dose verifications in EBRT.

Radiation construction and excellent performances of Ag NPs/TiO_(2)/PEG/PVP multifunctional aerogel:Adsorption-photocatalytic degradation,photosensitive antibacterial and cytotoxicity

A cutting-edge method known as photocatalytic antibacterial technology can effectively eliminate drug-resistant bacterial strains and boast a wide-ranging antimicrobial capability.In the study,a novel Ag NPs/TiO_(2)/PEG/PVP(ATPP)aerogel photocatalyst was synthesized by an electron beam in-situ radiation method using polyethylene glycol(PEG),polyvinylpyrrolidone(PVP),AgNO_(3),and TiO_(2)as raw materials.ATPP was characterized by X-ray diffraction spectroscopy(XRD),X-ray photoelectron spectroscopy(XPS)and solid ultraviolet diffuse reflectance spectroscopy(UV-Vis DRS).The results demonstrated that silver ions were reduced to silver nanoparticles by electron beam radiation method.At the same time,the doping of silver nanoparticles(Ag NPs)enhanced visible-light adsorption.The degradation rate of methylene blue(MB)on 5%(in mass)ATPP could reach 81%under visible light for 180 min.Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as model bacteria to explore the antimi-crobial properties of ATPP by zone of the inhibition method,plate counting method and live/dead bacterial staining.Cyclic antibacterial experiments showed that the antibacterial effect of ATPP was sustainable.Meanwhile,MTT assay and Hoechst33342/PI double staining were used to prove that the composite had good biocompatibility.The aerogel photocatalytic material has the potential to decrease microbial presence in both medical and environmental settings,making it a valuable tool for such applications.

Accelerated partial breast irradiation:Current evidence and future developments

Whole breast irradiation after breast-conserving surgery for early breast cancer has become one of the standard treatment modes for breast cancer and yields the same effect as radical surgery.Accelerated partial breast irradiation(APBI)as a substitute for whole breast irradiation for patients with early breast cancer is a hot spot in clinical research.APBI is characterised by simple high-dose local irradiation of the tumour bed in a short time,thus improving convenience for patients and saving costs.The implementation methods of APBI mainly include brachytherapy,external beam radiation therapy,and intraoperative radiotherapy.This review provides an overview of the clinical effects and adverse reactions of the main technologies of APBI and discusses the prospects for the future development of APBI.

Efficacy and safety of intraoperative radiotherapy in rectal cancer:A systematic review and meta-analysis

BACKGROUND In recent years,intraoperative radiotherapy(IORT)has been increasingly used for the treatment of rectal cancer.However,the efficacy and safety of IORT for the treatment of rectal cancer are still controversial.AIM To evaluate the value of IORT for patients with rectal cancer.METHODS We searched PubMed,Embase,Cochrane Library,Web of Science databases,and conference abstracts and included randomized controlled trials and observational studies on IORT vs non-IORT for rectal cancer.Dichotomous variables were evaluated by odds ratio(OR)and 95%confidence interval(CI),hazard ratio(HR)and 95%CI was used as a summary statistic of survival outcomes.Statistical analyses were performed using Stata V.15.0 and Review Manager 5.3 software.RESULTS In this study,3 randomized controlled studies and 12 observational studies were included with a total of 1460 patients,who are mainly residents of Europe,the United States,and Asia.Our results did not show significant differences in 5-year overall survival(HR=0.80,95%CI=0.60-1.06;P=0.126);5-year disease-free survival(HR=0.94,95%CI=0.73-1.22;P=0.650);abscess(OR=1.10,95%CI=0.67-1.80;P=0.713),fistulae(OR=0.79,95%CI=0.33-1.89;P=0.600);wound complication(OR=1.21,95%CI=0.62-2.36;P=0.575);anastomotic leakage(OR=1.09,95%CI=0.59-2.02;P=0.775);and neurogenic bladder dysfunction(OR=0.69,95%CI=0.31-1.55;P=0.369).However,the meta-analysis of 5-year local control was significantly different(OR=3.07,95%CI=1.66-5.66;P=0.000).CONCLUSION The advantage of IORT is mainly reflected in 5-year local control,but it is not statistically significant for 5-year overall survival,5-year disease-free survival,and complications.

Treatment results and prognostic analysis of 1093 primary nasopharyngeal carcinoma: the experience of a single institution of Guangzhou in the beginning of the 21st century

Objective： To analyze the treatment results of primary nasopharyngeal carcinoma （NPC） treated in our institution in the beginning of the 21st century to identify key failures and late effects for refining future treatments. Methods： 1093 patients with primary NPC treated during December 2001 and June 2003 were retrospectively analyzed. The distribution according to the AJCC/UICC （2002 edition） staging system was stage Ⅰ in 5.8%, stage Ⅱ 40.2%, stage Ⅲ 32.7% and stage Ⅳa-b 21.3%. Four different ERT techniques were used： fluoroscopy simulation conventional radiotherapy （CR） in 74.3% of patients, computer tomography simulation conventional radiotherapy （CT-sim CR） 14.2%, three-dimensional conformal radiotherapy （3D-CRT） 6.3%, intensity modulated radiotherapy （IMRT） 5.2%. In the whole series, 46.7% of patients had additional treatment with chemotherapy. Results： The 4-year local failure-free rate （LFFR）, nodal failure-free rate, distant metastasis-free rate, progression-free survival and overall survival （OS） was 89.6%, 96.1%, 85.9%, 73.0% and 82.4%, respectively. The stage was the most important prognostic factor. The 4-year OS and LFFR of patients treated by CR, CT-sim CR, 3D-CRT and IMRT was 80.2%, 89.8%, 89.8%, 92.4% and 87.7%, 96.4%, 91.0%, 96.5%, respectively. The morbidity and degree of xerostomia and trismus were lower in the patients treated by 3D-CRT and IMRT than by CR and CT-sim CR. Conclusion： Treatment results of primary NPC in our institution have been substantially improved. Distant metastasis is the main failure. The CT simulation and conformal radiotherapy can enhance the OS and LFFR, and conformal radiotherapy can reduce the morbidity and degree of late effects.

Radiotherapy for Carcinoma of the Esophagus: Progress of Treatment and Research in China

Carcinoma of the esophagus is a common malignancy in China. Radiotherapy is one of the most important modalities of treatment. This article provides a review of the natural history of this disease, the results of radiotherapy for esophageal cancer and the recent advances in radiation techniques in China. Significant progress has been made in this area of research and treatment. Combined treatment modalities and new therapies are being evaluated and may be expected to contribute to improved patient outcomes and better palliation of symptoms in the future.

Salvage treatments for prostate-specific antigen relapse of cT3N0M0 prostatic adenocarcinoma after radical prostatectomy combined with neoadjuvant androgen deprivation

Objective The aim of the study was to evaluate the efficiency of salvage treatments for prostate specific antigen(PSA)relapse of cT3N0M0 prostatic adenocarcinoma(PCa)after radical prostatectomy(RP)combined with neoadjuvant androgen deprivation(ADT).Methods A total of 332 patients with cT3N0M0 PCa were enrolled in the prospective study and received RP and pelvic lymph node dissection with neoadjuvant ADT for 3 months.All patients with PSA relapse were treated with salvage external beam radiation therapy(RT)and ADT for 6 months.Results The 5-year postoperative PSA relapse rate was 40.96%(136/332).The patients have been divided into the PSA relapse and PSA relapse-free groups in order to compare patient characteristics.The ratio of patients with Gleason score≥8 and positive surgical margin in the PSA relapse group were significantly higher than those of in the PSA relapse-free group(P=0.01).The mean duration between the start of operative treatment and PSA relapse was 31 months.Salvage treatment to all 136 PSA relapse patients led to favorable outcomes.PSA relapse was not observed after salvage treatment by the end of follow-up.The 5-year overall survival rates of the PSA relapse and PSA relapse-free groups were 94.9%and 93.9%,respectively.Conclusion In pursuit of curative treatment,our study showed that RP combined with neoadjuvant ADT is an aggressive multimodality strategy associated with lower PSA relapse and better survival outcomes for stage cT3N0M0 PCa patients.Patients with PSA relapse after RP may benefit from early aggressive salvage RT combined with short-term ADT.

Assessing keloid recurrence following surgical excision and radiation

Keloids are a fibroproliferative disorder that can result from a cutaneous injury to the reticular dermis.Recurrence rates as high as 100%have been reported following surgical excision alone.Consequently,a variety of post-surgical techniques have been employed to prevent keloid recurrence,including the use of radiation.Although numerous studies have shown post-excisional X-rays,electron beam,lasers and brachytherapy can reduce the rate of keloid recurrence,numerous inconsistencies,including a wide range of definitions for keloid recurrence,make it difficult to compare study outcomes.The review aims to examine the various means for defining keloid recurrence in clinical trials involving the use of radiation therapy.Searches of the Cochrane Library and PubMed were performed to identify the available information for post-surgical keloid recurrence following radiation therapy.Each identified study was reviewed for patient followup and criteria used to define keloid recurrence.The search results included clinical studies with external beam radiation,brachytherapy and superficial radiation therapy.Many studies did not include a definition of keloid recurrence,or defined recurrence only as the return of scar tissue.Other studies defined keloid recurrence based on patient self-assessment questionnaires,symptoms and scar elevation and changes in Kyoto Scar Scale,Japan Scar Workshop Scale and Vancouver Scar Scale scores.The results of this review indicate keloidectomy followed by radiation therapy provide satisfactory recurrence rates;however,clinical studies evaluating these treatments do not describe treatment outcomes or use different definitions of keloid recurrence.Consequently,recurrence rates vary widely,making comparisons across studies difficult.Keloid recurrence should be clearly defined using both objective and subjective measures.