Surgical Management of Lumbar Spinal Canal Stenosis with Instrumentation at the Yaounde Central Hospital: Comparison of Unilateral versus Bilateral Pedicle Screw Fixation Combined with Transforaminal Lumbar Interbody Fusion

Introduction: The choice of adopting unilateral pedicle screw fixation or using bilateral pedicle screw fixation in lumbar spinal stenosis remains controversial. In our context, very few studies have been performed comparing the clinical effectiveness of unilateral versus bilateral fixation in the surgical management of lumbar spinal canal stenosis. Objective: Evaluate the impact on quality of life and clinical efficacy of unilateral spondylodesis compared to bilateral spondylodesis in the surgical management of lumbar spinal canal stenosis at the Yaounde Central Hospital. Methods: This was a retrospective descriptive cross-sectional study for a period of 4 years, from June 2015 to June 2019. It involved all patients operated for lumbar canal stenosis and who underwent spondylodesis or spinal fusion at the neurosurgery department of the Yaounde Central Hospital. Results: A total of 68 participants were recruited during our study period. 32 (47%) of the study population were in the 50 - 60 age group, with a mean age of 56.98 years ranging from 41 to 75 years. Females, housewives and farmers were the most affected. In our study, 72% of patients had unilateral spondylodesis and 28% had bilateral fusion. Preoperatively, 71% of patients had insurmountable pain, refractory to medical treatment. At 3 months postoperatively, 73.7% of patients with bilateral setup had moderate pain compared to 69% of those with unilateral setup. At 6 months postoperatively, 79% of patients with bilateral fusion had mild pain compared to 82% of patients with unilateral setup. At 1 year postoperatively, all patients had mild pain. Preoperatively, 66.2% of patients were unable to walk and 19.1% of patients were bedridden according to the Oswestry score. At 3 months postoperatively, 10.2% of patients with unilateral setup were unable to walk compared to 10.5% of patients with bilateral fixation, while 67.3% of patients with unilateral fixation had moderate disability compared to 52.6% of patients with bilateral fixation. At 6 months postoperatively, 51% of patients with unilateral setup had moderate disability compared to 47.4% of patients with bilateral fixation, while 42.9% of patients with unilateral fixation had mild disability compared to 42.1% of patients with bilateral fixation. At 1 year postoperatively, 81.6% of patients who underwent unilateral fixation had only mild disability compared to 73.7% of patients with bilateral fixation. Conclusion: The assessment of quality of life according to the set-up used shows similar results at 3 months, 6 months and 1 year, with no statistically significant differences. Single-sided pedicle screw fixation combined with transforaminal lumbar interbody fusion or mounting has the advantage of being faster, with less bleeding and is less expensive compared to bilateral fixation.

Cost-effectiveness of patient specific vs conventional instrumentation for total knee arthroplasty:A systematic review and meta-analysis

BACKGROUND Over the past years,patient specific instrumentation(PSI)for total knee arthroplasty(TKA)has been implemented and routinely used.No clear answer has been given on its associated cost and cost-effectiveness when compared to conventional instrumentation(CI)for TKA.AIM To compare the cost and cost-effectiveness of PSI TKA compared to CI TKA.METHODS A literature search was performed in healthcare,economical healthcare,and medical databases(MEDLINE,EMBASE,CINAHL,Web of Science,Cochrane Library,EconLit).It was conducted in April 2021 and again in January 2022.Relevant literature included randomised controlled trials,retrospective studies,prospective studies,observational studies,and case control studies.All studies were assessed on methodological quality.Relevant outcomes included incremental cost-effectiveness ratio,quality-adjusted life years,total costs,imaging costs,production costs,sterilization associated costs,surgery duration costs and readmission rate costs.All eligible studies were assessed for risk of bias.Meta-analysis was performed for outcomes with sufficient data.RESULTS Thirty-two studies were included into the systematic review.Two were included in the metaanalysis.3994 PSI TKAs and 13267 CI TKAs were included in the sample size.The methodological quality of the included studies,based on Consensus on Health Economic Criteria-scores and risk of bias,ranged from average to good.PSI TKA costs less than CI TKA when considering mean operating room time and its associated costs and tray sterilization per patient case.PSI TKA costs more compared to CI TKA when considering imaging and production costs.Considering total costs per patient case,PSI TKA is more expensive in comparison to CI TKA.Meta-analysis comparing total costs for PSI TKA,and CI TKA showed a significant higher cost for PSI TKA.CONCLUSION Cost for PSI and CI TKA can differ when considering distinct aspects of their implementation.Total costs per patient case are increased for PSI TKA when compared to CI TKA.

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.

The CCD instrument background of the SMILE SXI

The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

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.

Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma surgery.Sixteen ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and instruments.After surgery,a subjective feedback survey about the user experience was taken.The experiment results showed that our system can help surgeons easily locate important tissue structures during surgery.The custom-made instruments also solved the shadowing problem in OCT imaging.Surgeons preferred to use the system in their future practice.

Journal of Measurement Science and Instrumentation

Journal of Measurement Science and Iustrumentation(CN14-1357/TH,ISSN 1674-8042)is published by North University of China.It is a comprehensive academic journal,aiming to present scientifie research papers in the fields of measurement science and instrumentation,ineluding general and instrumentation of measurement and control applied to such academie and industrial fields asprineiples.

AVEVA Instrumentation Engineer在仪表系统设计中的应用研究

本文分析AVEVA Instrumentation软件功能模块Engineer在仪表系统设计中的应用。重点探讨借助AVEVA Instrumentation软件实现跨专业、跨软件的数据交互开发及仪表专业清单文件、数据表的模板定制。

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.

Metallosis with spinal implant loosening after spinal instrumentation:A case report

BACKGROUND Spinal metallosis is a rare complication following spinal instrumentation whereby an inflammatory response to the metal implants results in the development of granulomatous tissue.CASE SUMMARY We describe the case of a 78-year-old woman who had recurrence of back pain 5 years after lumbar spine posterior decompression and instrumented fusion.Lumbar spine radiographs showed hardware loosening and magnetic resonance imaging showed adjacent segment disease.Revision surgery revealed evidence of metallosis intraoperatively.CONCLUSION Spinal metallosis can present several years after instrumentation.Radiography and computed tomography may demonstrate hardware loosening secondary to metallosis.Blood metal concentrations associated with spinal metallosis have yet to be established.Hence,metallosis is still an intraoperative and histopathological diagnosis.The presence of metallosis after spinal instrumentation likely indicates a more complex underlying problem:Pseudarthrosis,failure to address sagittal balance,infection,and cross-threading of set screws.Hence,identifying metallosis is important,but initiating treatment promptly for symptomatic implant loosening is of greater paramount.

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.

Exploring the Mysteries of the Universe, and Innovation Leading the Future——Astronomical Techniques and Instruments

Dear Readers:Astronomical Techniques and Instruments is a professional English journal of open access devoted to recent develop-ments,discoveries,and theories in astronomical techniques,methods,and instruments.It will serve as a platform for dis-course,learning,and information sharing for astronomic and astrophysics professionals worldwide.

Signal intensity changes of dentate nucleus on plain MR T1WI innasopharyngeal carcinoma patients after radiotherapy andmultiple injections of gadolinium-base contrast agent

Objective To observe changes of plain MR T1WI signal intensity of dentate nucleus in nasopharyngeal carcinoma patients after radiotherapy and multiple times of intravenous injection of gadolinium-based contrast agent(GBCA).Methods Fifty patients with pathologically confirmed nasopharyngeal carcinoma and received intensity-modulated radiotherapy were retrospectively enrolled as the nasopharyngeal carcinoma group,and 50 patients with other malignant tumors and without history of brain radiotherapy were retrospectively enrolled as the control group.All patients received yearly GBCA enhanced MR examinations for the nasopharynx or the head.T1WI signal intensities of the dentate nucleus and the pons on same plane were measured based on images in the year of confirmed diagnosis(recorded as the first year)and in the second to the fifth years.T1WI signal intensity ratio of year i(ranging from 1 to 5)was calculated with values of dentate nucleus divided by values of the pons(ΔSI i),while the percentage of relative changes of year j(ranging from 2 to 5)was calculated withΔSI j compared toΔSI 1(Rchange j).The values of these two parameters were compared,and the correlation ofΔSI and GBCA injection year-time was evaluated within each group.Results No significant difference of gender,age norΔSI 1 was found between groups(all P>0.05).The second to the fifth yearΔSI and Rchange in nasopharyngeal carcinoma group were all higher than those in control group(all P<0.05).Within both groups,ΔSI was positively correlated with GBCA injection year-time(both P<0.05).Conclusion Patients with nasopharyngeal carcinoma who underwent radiotherapy and multiple times of intravenous injection of GBCA tended to be found with gradually worsening GBCA deposition in dentate nucleus,for which radiotherapy might be a risk factor.

Postoperative chemoradiotherapy with capecitabine and oxaliplatin vs.capecitabine for pathological stage N2 rectal cancer

Objective:Several studies have been conducted on the effects and toxicity of adding oxaliplatin to fluorouracilbased or capecitabine-based chemoradiotherapy(CRT)regimens as significantly increasing the toxic response without benefit to survival.In this study,we further explored the role of these two postoperative CRT regimens in patients with pathological stage N2 rectal cancer.Methods:This study was a subgroup analysis of a randomized clinical trial.A total of 180 patients with pathological stage N2 rectal cancer were eligible,85 received capecitabine with radiotherapy(RT),and 95 received capecitabine and oxaliplatin with RT.Patients in both groups received adjuvant chemotherapy[capecitabine and oxaliplatin(XELOX);or fluorouracil,leucovorin,and oxaliplatin(FOLFOX)]after CRT.Results:At a median follow-up of 59.2[interquartile range(IQR),34.0−96.8]months,the three-year diseasefree survival(DFS)was 53.3%and 64.9%in the control group and the experimental group,respectively[hazard ratio(HR),0.63;95%confidence interval(95%CI),0.41−0.98;P=0.04].There was no significant difference between the groups in overall survival(OS)(HR,0.62;95%CI,0.37−1.05;P=0.07),the incidence of locoregional recurrence(HR,0.62;95%CI,0.24−1.64;P=0.33),the incidence of distant metastasis(HR,0.67;95%CI,0.42−1.06;P=0.09)and grade 3−4 acute toxicities(P=0.78).For patients with survival longer than 3 years,the conditional overall survival(COS)was significantly better in the experimental group(HR,0.39;95%CI,0.16−0.96;P=0.03).Conclusions:Our results indicated that adding oxaliplatin to capecitabine-based postoperative CRT is safe and effective in patients with pathological stage N2 rectal 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.

Prognosis of radiotherapy for esophageal cancer in elderly patients exceeding seventy-five years old

BACKGROUND Esophageal cancer(EC)often occurs in the elderly,with approximately 33%of patients aged≥75 years at the time of diagnosis.AIM To evaluate the prognostic factors for radiotherapy(RT)in elderly patients with unresectable EC.METHODS We retrospectively analyzed the clinical characteristics,toxic reactions,and survival information of EC patients aged≥75 years who underwent intensity-modulated RT at Lu’an Hospital of Anhui Medical University between January 2016 and September 2023.Kaplan-Meier analysis was used to draw the overall survival(OS)curves,and Cox regression analysis was employed to evaluate the influence of various clinical factors on the prognosis.RESULTS A total of 139 patients were enrolled.The median follow-up time was 52.0 months.The median OS was 20.0 months.The 1-year,2-year,3-year,and 5-year OS rates were 69.8%,38.7%,28.2%,and 17.5%,respectively.Univariate analysis showed that age,radiation dose,and chemotherapy had no significant impact on prognosis.Multivariate analysis indicated that clinical stage[Ⅲ-Ⅳa vsⅠ-Ⅱ,hazard ratio(HR)=2.421,95%confidence interval(CI):1.242-4.718,P=0.009;IVb vsⅠ-Ⅱ,HR=4.222,95%CI:1.888-9.438,P<0.001),Charlson comorbidity index(CCI)(0 vs≥1,HR=1.539,95%CI:1.015-2.332,P=0.042),and nutritional risk screening 2002(NRS2002)(<3 vs≥3,HR=2.491,95%CI:1.601-3.875,P<0.001)were independent prognostic factors for OS.CONCLUSION Our results suggest that CCI and NRS2002 were independent prognostic factors of OS for unresectable elderly EC patients undergoing RT.For elderly patients with EC,full attention should be given to biological age-related indicators,such as comorbidities and nutrition,when formulating treatment protocols.These factors should be considered in future clinical practice.

Potential of non-Western medicines in chemoradiotherapy for cervical cancer

This editorial explores the potential integration of non-Western medicine into radiotherapy for cervical cancer.While radiotherapy remains a radical treatment for cervical cancer,its associated toxicity and decline in quality of life can significantly impact patients’lives.Currently,most treatments are supportive,with no specific treatment options available in Western medicine.Non-Western medicine,often less toxic and easier to administer,has shown promising results when used alongside radiotherapy for cervical cancer.Despite these potential benefits,challenges such as limited evidence and restricted application areas persist.While non-Western medicines may offer potential improvements in chemoradiotherapy outcomes for cervical cancer,further research is necessary to substantiate these benefits.

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.

Evaluation of Air-Kerma and Absorbed Dose to Water for External Radiotherapy Beam Using Ionization Chamber

Radiotherapy is the most widely applied oncologic treatment modality utilizing ionizing radiation. A high degree of accuracy, reliability and reproducibility is required for a successful treatment outcome. Measurement using ionization chamber is a prerequisite for absorbed dose determination for external beam radiotherapy. Calibration coefficient is expressed in terms of air kerma and absorbed dose to water traceable to Secondary Standards Dosimetry Laboratory. The objective of this work was to evaluate the level of accuracy of ionization chamber used for clinical radiotherapy beam determination. Measurement and accuracy determination were carried out according to IAEA TRS 398 protocol. Clinical farmers type ionization chamber measurement and National Reference standard from Secondary Standards Dosimetry Laboratory were both exposed to cobalt-60 beam and measurement results compared under the same environmental conditions. The accuracy level between National Reference Standard and clinical radiotherapy standard was found to be −1.92% and −2.02% for air kerma and absorbed dose to water respectively. To minimize the effect of error and maximize therapeutic dose during treatment in order to achieve required clinical outcome, calibration factor was determined for air kerma (Nk) as 49.7 mGy/nC and absorbed dose to water ND, as 52.9 mGy/nC. The study established that radiotherapy beam measurement chain is prone to errors. Hence there is a need to independently verify the accuracy of radiation dose to ensure precision of dose delivery. The errors must be accounted for during clinical planning by factoring in calibration factor to minimize the systematic errors during treatment, and thereby providing enough room to achieve ±5% dose delivery to tumor target as recommended by ICRU.

Efficacy and Safety of Primary Radiotherapy in Combination with EGFR-TKIs for Non-Small Cell Lung Cancer Harboring EGFR Mutation

Objective: To evaluate the efficacy and safety of EGFR-TKI with the radiotherapy in EGFR mutant metastatic NSCLC. Methods: Retrospective analysis of 72 patients with stage IV lung cancer with EGFR-sensitive mutation. Patients in the A group were treated with the first-generation EGFR-TKI (Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor) combined with radiotherapy for primary tumors (34 cases). The B group was treated with the first-generation EGFR-TKI alone until the disease progressed (38 cases). PFS, OS, pulmonary infection and hematological toxicity during treatment were commented in both groups. Results: The objective remission rate was 47.1% (16/34) in the A group and 21.1% (8/38) in the B group. There was a significant difference between the two groups. There was no significant difference in hematological toxicity between the A group and the B group. There were 10 patients (29.4%) with degree II pulmonary infection in the A group and 3 patients (7.9%) in the B group. The difference between the two groups was statistically significant, suggesting that the incidence of pneumonia in the A group was higher than that in the B group. The median PFS (Progression-Free Survival)) and OS (Overall Survival) of the A group were significantly longer than those of the B group (16.5 months vs 9 months) and the median OS (36 months vs 19 months). The PFS and OS in the A group were significantly longer than those in the B group. Conclusion: EGFR-TKI combined with primary radiotherapy can significantly prolong the drug resistance time of EGFR mutant metastatic NSCLC.