The Dosimetric Characteristics and Potential Limitation in Clinical Application of a Low Energy Photon Intra-Operative Radiotherapy System

Purpose: To investigate the dosimetric characteristics of a low energy photon intra-operative radiotherapy (IORT) system and explore its potential limitation in clinical application. Methods: A special water phantom, a parallel-plate ionization chamber and an electrometer were used to measure the depth dose rate, isotropy of dose distribution in X/Y plane, dosimetry reproducibility of bare probe and spherical applicators of different size which were used in comparison with the system data. Results: The difference in depth dose rate between the measurement and system data for bare probe is -2.16% ± 1.36%, the range of the relative deviation for isotropy in the X/Y plane is between -1.9% and 2.1%. The difference in depth dose rate, transfer coefficient, isotropy in X/Y plane between the measurement and system data for the whole set of spherical applicators is -10.0% - 2.3%, -8.9% - 4.2% and -1.6% - 2.6%, respectively. Higher surface dose rate and steeper gradient depth dose are observed in smaller spherical applicators. The depth dose rate and isotropy for bare probe and spherical applicators have been shown good reproducibility. The uncertainty of measurement is associated with the positioning accuracy, energy response, noise current and correction function f’(R). Conclusions: Thorough commissioning of the low energy photon IORT system helps us better understand the dosimetry characteristics, verify the system data, obtain adequate data for clinical application and routine quality assurance. The steep gradient depth dose and limited treatment range may restrain its potential in clinical application.

Stereotactic body radiotherapy in pancreatic adenocarcinoma

Background:Stereotactic body radiotherapy(SBRT)in pancreatic cancer allows high delivery of radiation doses on tumors without affecting surrounding tissue.This review aimed at the SBRT application in the treatment of pancreatic cancer.Data sources:We retrieved articles published in MEDLINE/PubMed from January 2017 to December 2022.Keywords used in the search included:“pancreatic adenocarcinoma”OR“pancreatic cancer”AND“stereotactic ablative radiotherapy(SABR)”OR“stereotactic body radiotherapy(SBRT)”OR“chemoradiotherapy(CRT)”.English language articles with information on technical characteristics,doses and fractionation,indications,recurrence patterns,local control and toxicities of SBRT in pancreatic tumors were included.All articles were assessed for validity and relevant content.Results:Optimal doses and fractionation have not yet been defined.However,SBRT could be the standard treatment in patients with pancreatic adenocarcinoma in addition to CRT.Furthermore,the combination of SBRT with chemotherapy may have additive or synergic effect on pancreatic adenocarcinoma.Conclusions:SBRT is an effective modality for patients with pancreatic cancer,supported by clinical practice guidelines as it has demonstrated good tolerance and good disease control.SBRT opens a possibility of improving outcomes for these patients,both in neoadjuvant treatment and with radical intent.

Hemostatic radiotherapy for bleeding gastrointestinal

Hemostatic radiotherapy is a non-invasive treatment for bleeding gastrointestinal(GI)tumors,promoting tumor shrinkage,blood supply reduction,and fibrotic tissue formation.It is effective in cases where traditional interventions are insufficient or contraindicated and can prevent recurrent bleeding in patients with GI bleeding histories.Hypofractionation schedules are also effective for tumor control and patient compliance.

Present situation and prospect of immunotherapy for unresectable locally advanced esophageal cancer during peri-radiotherapy

Four major studies(Checkmate577,Keynote-590,Checkmate649 and Attraction-4)of locally advanced esophageal cancer published in 2020 have established the importance of immunotherapy,represented by anti-programmed death protein(PD)-1 in postoperative adjuvant treatment and advanced first-line treatment of locally advanced or advanced esophageal cancer and esophagogastric junction cancer,from the aspects of proof of concept,long-term survival,overall survival rate and progression-free survival.For unresectable or inoperable nonmetastatic esophageal cancer,concurrent radiotherapy and chemotherapy is the standard treatment recommended by various guidelines.Because its curative effect is still not ideal,it is necessary to explore radical radiotherapy and chemotherapy in the future,and it is considered to be promising to combine them with immunotherapeutic drugs such as anti-PD-1.This paper mainly discusses how to combine radical concurrent radiotherapy and chemotherapy with immunotherapy for unresectable local advanced esophageal cancer.

Targeting the organelle for radiosensitization in cancer radiotherapy

Radiotherapy is a well-established cytotoxic therapy for local solid cancers, utilizing high-energy ionizing radiation to destroy cancer cells. However, this method has several limitations, including low radiation energy deposition, severe damage to surrounding normal cells, and high tumor resistance to radiation. Among various radiotherapy methods, boron neutron capture therapy (BNCT) has emerged as a principal approach to improve the therapeutic ratio of malignancies and reduce lethality to surrounding normal tissue, but it remains deficient in terms of insufficient boron accumulation as well as short retention time, which limits the curative effect. Recently, a series of radiosensitizers that can selectively accumulate in specific organelles of cancer cells have been developed to precisely target radiotherapy, thereby reducing side effects of normal tissue damage, overcoming radioresistance, and improving radiosensitivity. In this review, we mainly focus on the field of nanomedicine-based cancer radiotherapy and discuss the organelle-targeted radiosensitizers, specifically including nucleus, mitochondria, endoplasmic reticulum and lysosomes. Furthermore, the organelle-targeted boron carriers used in BNCT are particularly presented. Through demonstrating recent developments in organelle-targeted radiosensitization, we hope to provide insight into the design of organelle-targeted radiosensitizers for clinical cancer treatment.

Enhancing Precision in Radiotherapy Delivery: Validating Monte Carlo Simulation Models for 6 MV Elekta Synergy Agility LINAC Photon Beam Using Two Models of the GAMOS Code

The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits has become indispensable for research aimed at precisely determining the dose in radiotherapy. Among the numerous algorithms developed in recent years, the GAMOS code, which utilizes the Geant4 toolkit for Monte Carlo simula-tions, incorporates various electromagnetic physics models and multiple scattering models for simulating particle interactions with matter. This makes it a valuable tool for dose calculations in medical applications and throughout the patient’s volume. The aim of this present work aims to vali-date the GAMOS code for the simulation of a 6 MV photon-beam output from the Elekta Synergy Agility linear accelerator. The simulation involves mod-eling the major components of the accelerator head and the interactions of the radiation beam with a homogeneous water phantom and particle information was collected following the modeling of the phase space. This space was po-sitioned under the X and Y jaws, utilizing three electromagnetic physics mod-els of the GAMOS code: Standard, Penelope, and Low-Energy, along with three multiple scattering models: Goudsmit-Saunderson, Urban, and Wentzel-VI. The obtained phase space file was used as a particle source to simulate dose distributions (depth-dose and dose profile) for field sizes of 5 × 5 cm2 and 10 × 10 cm2 at depths of 10 cm and 20 cm in a water phantom, with a source-surface distance (SSD) of 90 cm from the target. We compared the three electromagnetic physics models and the three multiple scattering mod-els of the GAMOS code to experimental results. Validation of our results was performed using the gamma index, with an acceptability criterion of 3% for the dose difference (DD) and 3 mm for the distance-to-agreement (DTA). We achieved agreements of 94% and 96%, respectively, between simulation and experimentation for the three electromagnetic physics models and three mul-tiple scattering models, for field sizes of 5 × 5 cm2 and 10 × 10 cm2 for depth-dose curves. For dose profile curves, a good agreement of 100% was found between simulation and experimentation for the three electromagnetic physics models, as well as for the three multiple scattering models for a field size of 5 × 5 cm2 at 10 cm and 20 cm depths. For a field size of 10 × 10 cm2, the Penelope model dominated with 98% for 10 cm, along with the three multiple scattering models. The Penelope model and the Standard model, along with the three multiple scattering models, dominated with 100% for 20 cm. Our study, which compared these different GAMOS code models, can be crucial for enhancing the accuracy and quality of radiotherapy, contributing to more effective patient treatment. Our research compares various electro-magnetic physics models and multiple scattering models with experimental measurements, enabling us to choose the models that produce the most reli-able results, thereby directly impacting the quality of simulations. This en-hances confidence in using these models for treatment planning. Our re-search consistently contributes to the progress of Monte Carlo simulation techniques in radiation therapy, enriching the scientific literature.

Radiotherapy for hyoid bone metastasis from lung adenocarcinoma:A case report

BACKGROUND Metastasis to the hyoid bone is an exceptionally rare occurrence,with documented cases limited to breast,liver,colon,skin,lung,and prostate cancers.This report highlights an unusual case involving the metastasis of lung adenocarcinoma to the hyoid bone,accompanied by a distinctive headache.Previous documentation involved surgical resection of the hyoid mass.We present a case displaying the benefits of palliative radiotherapy.CASE SUMMARY A 72-year-old non-smoking,non-alcoholic woman,initially under investigation for a year-long elevation in absolute lymphocyte count,presented with a monthlong history of intermittent throat pain.Despite negative findings in gastroenterological and otolaryngologic examinations,a contrast-enhanced chest computed tomography scan revealed a mediastinal mass and questionable soft tissue thickening in her left anterolateral neck.Subsequent imaging and biopsies confirmed the presence of lung adenocarcinoma metastasis to the hyoid bone.The patient was treated with platinum-based chemo-immunotherapy along with pembrolizumab.Ultimately,the lung cancer was unresponsive.Our patient opted for palliative radiation therapy instead of surgical resection to address her throat pain.As a result,her throat pain was alleviated,and it also incidentally resolved her chronic headaches.This is the second documented case of lung adenocarcinoma metastasizing to the hyoid bone.CONCLUSION Palliative radiotherapy may add to the quality of life in symptomatic patients with cancer metastatic to the hyoid bone.

Chemotherapy and radiotherapy:Could they contribute to the development of new tumors and metastases?

Objective: Both chemotherapy and radiotherapy have demonstrated high effectiveness as the best mechanisms in the fight against cancer;however, various studies seem to confirm that they could also favor the development of other unwanted effects of great importance for the patient. The main objective of this study is to find out the possible existence of this type of links. Method: This is a systematic literature review that seeks to find out which and how long cases of late interactions related to chemotherapy and radiotherapy treatments have been known. The bibliographic review was carried out based on references published in the last five years. Results: Various studies confirm the possible relationship between chemotherapy and radiotherapy treatments with the development of new undesirable side effects, especially as a consequence of the hepatotoxicity generated in the case of chemotherapy and radiation in radiotherapy. However, in this last type of treatment, the problems raised are really few. Conclusions: The existence of a risk of suffering new unwanted side effects after different types of treatment seems to have been demonstrated, especially in the case of chemotherapy. In the case of radiotherapy, adverse effects are practically non-existent, although they are no less important.

Changes in acute and late toxicity and patient-reported health-related quality of life following radiotherapy in women with breast cancer:A 1-year longitudinal study

Objective:The objective of this study was to investigate the frequency of acute and late toxicities,as well as changes in the quality of life(QOL)for breast cancer patients following radiotherapy(RT).Materials and Methods:A total of 108 breast cancer women were recruited for this prospective study.Data were collected at various intervals;prior to,and 1,3,6 months,and 1 year after radiation therapy.The primary outcomes were toxicity radiation therapy oncology group/European Organization for Research and Treatment of Cancer(EORTC)criteria.Our secondary outcome was QOL,measured using EORTC QLQ-C30 and Edmonton Symptom Assessment Scale.We employed Friedman’s two-way analysis to evaluate the changes in QOL over the course of 1 year.Results:The early toxicities that are most commonly experienced include pharyngeal,skin,and mucous membrane toxicity.Late toxicities frequently involve skin and submucosal toxicity.To measure patient functionality,all functional subscale scores except for the patient’s emotional state increased over time compared to pre-RT.Symptoms of the patients,which were included in the QOL symptom scale,decreased during the follow-up period,except for fatigue;however,changes in pain,insomnia,and loss of appetite did not significantly change.We identified the analogous symptom profiles in Edmonton.Although patients’overall health scores declined in the 1st and 3rd months after radiotherapy(RT),they rebounded at 6 and 12 months.Conclusion:For breast cancer patients,RT did not adversely affect functional capacity or exacerbate symptoms,but persistent fatigue did increase during the observation period.Health-care professionals ought to devise strategies to assist patients with skin toxicity and fatigue.

Impact of intra-operative cholangiography and parenchymal resection to donor liver function in living donor liver transplantation

BACKGROUND: Living donor liver transplantation(LDLT)has been widely accepted over the past decade, and hepatic dysfunction often occurs in the donor in the early stage after liver donation. The present study aimed to evaluate the effect of intraoperative cholangiography(IOC) and parenchymal resection on liver function of donors in LDLT, and to assess the role of IOC in influencing the biliary complications and improving the overall outcome.METHODS: Data from 40 patients who had donated their right lobes for LDLT were analyzed. Total bilirubin(TB), alanine aminotransferase(ALT), aspartate aminotransferase(AST),alkaline phosphatase(ALP) and γ-glutamyl transpeptidase(GGT)at different time points were compared, and the follow-up data and the biliary complications were also analyzed.RESULTS: The ALT and AST values were significantly increased after IOC(P<0.001) and parenchymal resection(P<0.001).However, the median values of TB, ALP and GGT were not significantly influenced by IOC(P>0.05) or parenchymal resection(P>0.05). The biochemical changes caused by IOC or parenchymal resection were not correlated with the degree of post-operative liver injury or the recovery of liver function. The liver functions of the donors after operation were stable, and none of the donors suffered from biliary stenosis or leakage during the follow-up.CONCLUSIONS: IOC and parenchymal resection may induce a transient increase in liver enzymes of donors in LDLT, but do not affect the recovery of liver function after operation. Moreover,the routine IOC is helpful to clarify the division line of the hepatic duct, thus reducing the biliary complication rate.

Establishment of a prediction model for severe acute radiation enteritis associated with cervical cancer radiotherapy

BACKGROUND Cervical cancer is one of the most common gynecological malignant tumors.Radiation enteritis(RE)leads to radiotherapy intolerance or termination of radiotherapy,which negatively impacts the therapeutic effect and seriously affects the quality of life of patients.If the incidence of RE in patients can be predicted in advance,and targeted clinical preventive treatment can be carried out,the side effects of radiotherapy in cervical cancer patients can be significantly reduced.Furthermore,accurate prediction of RE is essential for the selection of individualized radiation dose and the optimization of the radiotherapy plan.AIM To analyze the relationships between severe acute RE(SARE)of cervical cancer radiotherapy and clinical factors and dose-volume parameters retrospectively.METHODS We included 50 cervical cancer patients who received volumetric modulated arc therapy(VMAT)from September 2017 to June 2018 in the Department of Radiotherapy at The First Affiliated Hospital Soochow University.Clinical and dose-volume histogram factors of patients were collected.Logistic regression analysis was used to evaluate the predictive value of each factor for SARE.A nomogram to predict SARE was developed(SARE scoring system≥3 points)based on the multiple regression coefficients;validity was verified by an internal verification method.RESULTS Gastrointestinal and hematological toxicity of cervical cancer VMAT gradually increased with radiotherapy and reached the peak at the end of radiotherapy.The main adverse reactions were diarrhea,abdominal pain,colitis,anal swelling,and blood in the stool.There was no significant difference in the incidence of gastrointestinal toxicity between the radical and postoperative adjuvant radiotherapy groups(P>0.05).There were significant differences in the small intestine V_(20),V_(30),V_(40),and rectal V40 between adjuvant radiotherapy and radical radiotherapy after surgery(P<0.05).Univariate and multivariate analyses revealed anal bulge rating(OR:14.779,95%CI:1.281-170.547,P=0.031)and disease activity index(DAI)score(OR:53.928,95%CI:3.822-760.948,P=0.003)as independent predictors of SARE.CONCLUSION Anal bulge rating(>0.500 grade)and DAI score(>2.165 points)can predict SARE.The nomogram shows potential value in clinical practice.

Implications of recent neoadjuvant clinical trials on the future practice of radiotherapy in locally advanced rectal cancer

Over the last two decades, the standard treatment for locally advanced rectal cancer(LARC) has been neoadjuvant chemoradiotherapy plus total mesorectal excision followed by adjuvant chemotherapy. Total neoadjuvant treatment(TNT) and immunotherapy are two major issues in the treatment of LARC. In the two latest phase Ⅲ randomized controlled trials(RAPIDO and PRODIGE23), the TNT approach achieved higher rates of pathologic complete response and distant metastasis-free survival than conventional chemoradiotherapy. Phase I/II clinical trials have reported promising response rates to neoadjuvant(chemo)-radiotherapy combined with immunotherapy. Accordingly, the treatment paradigm for LARC is shifting toward methods that increase the oncologic outcomes and organ preservation rate. However, despite the progress of these combined modality treatment strategies for LARC, the radiotherapy details in clinical trials have not changed significantly. To guide future radiotherapy for LARC with clinical and radiobiological evidence, this study reviewed recent neoadjuvant clinical trials evaluating TNT and immunotherapy from a radiation oncologist’s perspective.

Stereotactic body radiotherapy combined with sintilimab in patients with recurrent or oligometastatic hepatocellular carcinoma: A phase Ⅱ clinical trial

BACKGROUND Stereotactic body radiotherapy(SBRT)and programmed cell death 1 inhibitors have shown potential in treating hepatocellular carcinoma(HCC)in retrospective studies.AIM To evaluate the efficacy of combining SBRT with sintilimab for patients with recurrent or oligometastatic HCC.METHODS This trial involved patients with recurrent or oligometastatic HCC intravenously treated with SBRT plus sintilimab every 3 wk for 12 mo or until disease progression.The primary endpoint was progression-free survival(PFS).RESULTS Twenty-five patients were enrolled from August 14,2019,to August 23,2021.The median treatment duration was 10.2(range,0.7-14.6)months.SBRT was delivered at a median dose of 54(range,48-60)Gy in 6(range,6-10)fractions.The median follow-up time was 21.9(range,10.3-39.7)mo,and 32 targeted lesions among 25 patients were evaluated for treatment response according to the Response Evaluation Criteria in Solid Tumors version 1.1.The median PFS was 19.7 mo[95%confidence interval(CI):16.9-NA],with PFS rates of 68%(95%CI:52-89)and 45.3%(95%CI:28-73.4)at 12 and 24 mo,respectively.The median overall survival(OS)was not reached,with OS rates of 91.5%(95%CI:80.8-100.0)and 83.2%(95%CI:66.5-100.0)at 12 and 24 mo,respectively.The 1-and 2-year local control rate were 100%and 90.9%(95%CI:75.4%-100.0%),respectively.The confirmed objective response rate and disease control rate was 96%,and 96%,respectively.Most adverse events were graded as 1 or 2,and grade 3 adverse events were observed in three patients.CONCLUSION SBRT plus sintilimab is an effective,well-tolerated treatment regimen for patients with recurrent or oligometastatic HCC.

Role of Intra-Operative Nerve Monitoring in Thyroidectomies: An Institutional Review

Injury to the Recurrent Laryngeal Nerve (RLN) is a worrisome complication of a thyroidectomy. Intra-operative nerve monitoring (IONM) of the RLN has gained prevalence as an aid to prevent injury. We reviewed our series and other studies in literature for insight. A chart review was carried out to identify all patients who underwent a thyroidectomy between 2005 and 2010. IONM was implemented by the Otolaryngology service in 2007. All identified patients were separated into three groups: 1) Otolaryngology service with IONM, 2) Otolaryngology service without IONM, and 3) General Surgery service without IONM. Several factors were noted, including age, sex, thyroid disease, extent of thyroidectomy, and RLN injury along with recovery. 230 patients underwent thyroidectomy from 2005-2010. 60 patients were isolated in the IONM-Otolaryngology group with 3 patients suffering injury. 109 patients underwent a thyroidectomy by the Otolaryngology service without IONM with 8 patients suffering nerve damage. In the third group, 61 patients underwent a thyroidectomy by General Surgery without IONM with 4 patients suffering damage. Of the thyroid pathology, 10 patients had Multinodular Goiter while 4 had Papillary Cancer and 1 had a Follicular Adenoma. The most severe complication of a thyroidectomy is RLN injury. In order to further decrease the risk of RLN injury, IONM has been employed. From our review and other studies, there does not appear to be a significant difference in rates of RLN injury with or without use of nerve monitoring. An interesting note is the increased prevalence of nerve injuries in Multinodular Goiter—a finding that merits further study to evaluate the role of IONM.

Simultaneous integrated dose reduction intensity-modulated radiotherapy effectively reduces cardiac toxicity in limited-stage small cell lung cancer

Objective:To assess the clinical outcomes and toxicities of once daily(QD)simultaneous dose reduction intensity-modulated radiotherapy(SDR-IMRT-QD;SDR-QD)versus conventional QD IMRT(C-QD)and twice daily(BID)IMRT in patients with limited-stage small cell lung cancer(LS-SCLC).Methods:After propensity score matching(PSM),a retrospective analysis involving 300 patients with LS-SCLC treated using SDR-QD,C-QD,or BID was performed from January 1,2014 to December 31,2019.The prescribed irradiation dose in the SDR-QD cohort was 60 Gy/PGTV and 54 Gy/PTV QD.The radiation dose was 60 Gy for both PGTV and PTV QD in the C-QD cohort.The radiation dose was 45 Gy for both PGTV and PTV in the BID cohort.Toxicities,short-term effects,and survival outcomes were recorded.A meta-analysis on the protective effects of pharmaceuticals for cardiac toxicities induced by anti-tumor therapy was performed.Results:The median overall survival time(MST)in the 3 cohorts were 32.7 months(SDR-QD),26.3 months(C-QD),and 33.6 months(BID);the differences between groups were statistically significant.Lower toxicities and doses to organs-at-risk(OARs)occurred in the SDR-QD and BID cohorts.Further,the cardiac dose dosimetric parameter Vheart40 was negatively associated with survival(r=-0.35,P=0.007).A Vheart40 value of 16.5%was recommended as a cut-off point,which yielded 54.7%sensitivity and 85.7%specificity for predicting negative survival outcomes.The meta-analysis indicated that pharmaceuticals significantly reduced the cardiac toxicities induced by chemotherapy,but not radiotherapy.Conclusions:SDR-QD was shown to have similar toxicities and survival compared with BID,but fewer toxicities and better survival than C-QD.In addition,cardiac dose exposure was negatively associated with survival.Thus,16.5%of the cardiac dosimetric parameter Vheart40 is recommended as the cut-off point,and a Vheart40>16.5%predicts poor survival.

Stereotactic ablative body radiotherapy for oligometastatic inguinal lymph node in castrate resistant prostate cancer

Dear Editor,Introduction of prostate-specific membrane antigen positron-emission tomography/contrast-enhanced computed tomography(PSMA PET/CECT)for prostate cancer staging and follow-up have increased detection of metastases even in non-regional nodes,often in oligometastatic or oligorecurrent state[1].Some of these merit metastases-directed therapy(MDT)such as surgery or radiotherapy(RT)with curative intent.

Profile of Radiotherapy Side Effects in Patients Treated for Cervical Cancer in Cameroon: Case of the Douala General Hospital

Background: Radiotherapy is one of the main therapeutic strategies used in cervical cancer. The first radiotherapy services in Cameroon have existed since 1987 and still treat by conventional radiation techniques. With the evolution of radiation techniques, acute, subacute, and late complications are minimized. Our study aimed to describe the profile of side effects in patients with uterine cervix cancer treated by conventional radiotherapy, still used in our services. Methods: This was a retrospective and descriptive study of the records of patients treated in the radiotherapy department of the Douala General Hospital from January 2015 to December 2019. Data concerning radiation-induced toxicities were collected using the CTCAE Version 4.0 classification. Data analysis was performed using SPSS version 20.0. Results: A total of 270 records were selected. The median age was 54 years. The mean total radiation dose was 55.9 ± 11.8 Gy and 71.1% of patients were treated for less than 8 weeks. We found a frequency of 66.7% of radio-induced lesions with 99% being acute. The main acute lesions encountered were radio dermatitis (40%), radiation cystitis (17.7%), and radiation proctitis (17.1%). As late lesions, we found one case of vaginal fibrosis (0.4%). Exclusive radiotherapy, classical fractionation, and total doses lower than 45 Gy seemed to decrease the toxicity linked to conventional radiotherapy. Conclusion: The frequency of side effects of radiotherapy for cervical cancer at the Douala General Hospital remains high. Early lesions are the most encountered but strategies should be put in place to better evaluate late lesions.

Comparative Study between Patients Treated with Conventional Radiotherapy and IMRT with Chemotherapy for Stage III - IVA Nasopharyngeal Carcinoma: A Single Institution Retrospective Report

Introduction: Nasopharyngeal carcinomas are the most radiation-sensitive tumours, and radiotherapy alone provides better local control. Objectives: To evaluate the clinical efficacy and acute and late toxicities of two different treatment regimens for locally advanced nasopharyngeal carcinoma. Methods: From 2014 to 2017, 150 cases of stage III and 68 cases of stage IVA nasopharyngeal carcinoma were treated. Of these, 137 received conventional radiotherapy plus chemotherapy, and 81 received intensity-modulated radiotherapy plus chemotherapy. Chemotherapy was given either as induction, concurrent or adjuvant therapy. Survival rates were calculated according to Kaplan Meier and compared with the Log-rank test. The RTOG or EORTC criteria were used to assess acute and late toxicities. Results: The median follow-up time was 21.5 months, and the 2-year locoregional relapse-free survival, distant metastases-free survival, and overall survival rates in the conventional radiotherapy plus chemotherapy group were 76%, 71% and 77%, respectively;in the intensity-modulated radiotherapy plus chemotherapy group, they were 97%, 84%, and 100%, respectively. The difference in survival between the two groups was significant (χ2 = 5.06, P = 0.028). The incidence of grade 2 and 3 xerostomia one year after radiotherapy was 45.1% and 30.9% versus 33.3% and 0%. Conclusion: Compared with conventional radiotherapy plus chemotherapy, intensity-modulated radiotherapy plus chemotherapy offers better locoregional relapse-free survival and overall survival in patients with stage III and IVA nasopharyngeal carcinoma, and may significantly reduce the occurrence of radiation-induced xerostomia.

Multi-institutional analysis of cervical esophageal carcinoma patients treated with definitive chemoradiotherapy: TROD 01-005 study

The aim of this study was to examine the prognostic factors and treatment outcomes of cervical esophageal carcinoma(CEC)patients who underwent definitive chemoradiotherapy(CRT).The clinical data of 175 biopsyconfirmed CEC patients treated with definitive CRT between April 2005 and September 2021 were retrospectively analyzed.The prognostic factors predicting overall survival(OS),progression-free survival(PFS),and local recurrence-free survival(LRFS)were assessed in uni-and multivariable analyses.The median age of the entire cohort was 56 years(range:26–87 years).All patients received definitive radiotherapy with a median total dose of 60 Gy,and 52%of the patients received cisplatin-based concurrent chemotherapy.The 2-year OS,PFS,and LRFS rates were 58.8%,46.9%,and 52.4%,respectively,with a median follow-up duration of 41.6 months.Patients’performance status,clinical nodal stage,tumor size,and treatment response were significant prognostic factors for OS,PFS,and LRFS in univariate analysis.Non-complete treatment response was an independent predictor for poor OS(HR=4.41,95%CI,2.78–7.00,p<0.001)and PFS(HR=4.28,95%CI,2.79–6.58,p<0.001),whereas poor performance score was a predictor for worse LRFS(HR=1.83,95%CI,1.12–2.98,p=0.02)in multivariable analysis.Fifty-two patients(29.7%)experienced grade II or higher toxicity.In this multicenter study,we demonstrated that definitive CRT is a safe and effective treatment for patients with CEC.Higher radiation doses were found to have no effect on treatment outcomes,but a better response to treatment and a better patient performance status did.

Establishment of image-guided radiotherapy of orthotopic hepatocellular carcinoma mouse model

Background:Hepatocellular carcinoma(HCC)is the most common type of liver cancer.Recently,developments in radiotherapy technology have led to radiotherapy becoming one of the main therapeutics of HCC.Therefore,a suitable animal model for radiotherapy of the orthotopic HCC mouse model is urgently needed.Methods:In the present study,Hepa1-6 cells were injected into the liver of C57BL/6 mice in situ to mimic the pathological characteristics of the original HCC.Tumor formation was monitored by applying magnetic resonance imaging techniques and verified by H&E histopathological staining,AFP staining,and Ki67 staining.A single dose of 10 Gy X-ray was applied to simulate clinical radiotherapy plans using image-guided radiotherapy(IGRT)equipment.The efficiency of radiotherapy was then assessed by examining tumor size and weight one week after radiation.Cleaved-caspase3 staining and TUNEL were used to assess apoptosis in tumor tissues.Results:Intrahepatic tumor development was detected in the liver according using MRI.A high-density shadow could be seen 10 days after cell injection,which indicated the formation of HCC in vivo.The tumors grew steadily bigger,and underwent precision radiotherapy 20 days after injection.The typical pathological characteristics of HCC,such as large,deeply stained nuclei and irregular cell size,were visible with H&E staining.After radiotherapy,significantly higher expression of the immunohistochemical markers Ki67 and AFP were detected in tumor tissue than in the nearby normal tissue.Compared with the control group,the tumor volume(p=0.05)and weight(p<0.05)of the irradiated group were significantly reduced.In addition,a higher frequency of apoptosis was identified in irradiated HCC tumor tissue using the TUNEL and cleaved-caspase3 staining assay.Conclusions:In a well-established orthotopic HCC model,MRI was utilized to monitor the formation of tumors,and IGRT was used to simulate clinical radiotherapy.The present study could provide a suitable preclinical system for HCC radiotherapyrelated studies.