Comparison Of I¹²⁵ Seeds Brachytherapy Conformal Radiotherapy And Stereotactic Ablative Radiotherapy On Early Non-small Cell Lung Cancer

[Background]Lung cancer is a kind of malignant tumor with highest incidence and mortality.Non-small cell lung cancer(NSCLC)accounts for 75%-80%of lung cancer.Surgery was still the best treatment for early NSCLC(T1-2N0M00).For inoperable early NSCLC.radiotherapy is one of optional treatment.Stereotactic ablative radiotherapy(SBRT)showed a high local control rate and long survival time.I125 seeds brachytherapy(RSB)joint conformal radiotherapy(3DCRT)is characterized as high local dose(>100cGy).low damage for surrounding normal tissues.But short distance from radiation may lead to relapse in sub tumors region because of under-dosage.In this study.local control rates,one year survival rates,toxic and side effects were used to compare I125 seeds brachytherapy(RSB)joint conformal radiotherapy(3DCRT)in sub tumors region with stereotactic ablative radiotherapy(SBRT).[Objective]To compare CT based I125 seeds brachytherapy(RSB)joint conformal radiotherapy(3DCRT)and stereotactic ablative radiotherapy(SBRT)on early non-small cell lung cancer(NSCLC).[Methods]1.clinical dataBetween March 2014 and June 2017,in Shandong provincial hospital,30 patients with histological or cytological confirmation of adenocarcinoma squamous lung cancer was considered as candidates in this pilot study.All 30 cases consists of 23 males and 7 females.17 age?60 and 13 age<60,6 patients were ? stage(T1N0M0),24 patients were ? stage(T2N0M0).2.the distribution of treatment groupAll cases Were divided into two groups.Group A:20 cases experienced I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT).300cGy*10 times Group B:10 cases experienced stereotactic ablative radiotherapy(SBRT).800cGy*6 times3.Treatment3.1 I125 seeds brachytherapy(RSB):Preoperative CT was performed with 5 mm thickness.In treatment planning system(TPS),preplan was to confirm implantation guide pin number and location,particle number and location,total activity and dose distribution of target area(including tumor and normal tissue).The I125 seeds implantation was guided by CT.According to the dose distribution requirement,uniform distribution or peripheral dense,center sparse cloth source method was chosen.During particle implantation,TPS was used to optimize dose,adjust particle location,correct unevenness,protect important organs adjacent to the target area.CT was used to check results.The dose distribution of target area and adjacent normal tissue was calculated by TPS.Supplementary treatment would be added if necessary.The target area was defined as the boundary of the CT lung window tumor extending 5mm.D90(The minimum dose that covers 90%of the target volume)>110Gy.MPD(matched peripheral dose):110Gy-140Gy.Particle activity:0.6-0.7mic.3.2 3Dconformal radiotherapy(3DCRT):Thermoplastic film fixation at supine position.Preoperative CT was performed with 5 mm thickness.The input of 3D treatment planning system(TPS)was location reconstruction pictures.The target area is defined in accordance with the International Commission on Radiation Units and Measurements(ICRU)50 document.Gross tumor volume(GTV)is the primary lesion.The boundary is a lung window showing lesions on CT.The clinical target volume(CTV)was 1cm outside GTV.Double checked by radiotherapy physicians and physical therapists.The planned target area(PTV)is 0.5cm outside CTV.The physiologist drew the outline of the body and the important organs.Conformal treatment was performed in 3-4 fields(300cGy*10 times,5 times/week).The treatment plan was optimized by dose-volume histogram(DVH).90%of isodose curves covered PTV.Spinal cord exposure ?30Gy.Esophageal exposure?30Gy.Heart exposure ?20Gy.The three dimensional conformal treatment planning system calculated and confirmed set-up reference points.was used for radiotherapy.3DCRT was 2 weeks after I125 seeds brachytherapy(RSB)3.3 Stereotactic ablative radiotherapy(SBRT):Thermoplastic film fixation at supine position.Preoperative CT was performed with 5 mm thickness.The input of 3d treatment planning system was location reconstruction pictures.The target area is defined in accordance with the International Commission on Radiation Units and Measurements(ICRU)50 document.Gross tumor volume(GTV)is the primary lesion.The boundary is a lung window showing lesions on CT.The clinical target volume(CTV)was 1cm outside GTV.Double checked by radiotherapy physicians and physical therapists.The planned target area(PTV)is 0.5cm outside CTV.The physiologist drew the outline of the body and the important organs.Conformal treatment was performed in 3-4 fields(800cGy*6 times,3 times/week).The treatment plan was optimized by dose-volume histogram(DVH).90%of isodose curves covered PTV.Spinal cord exposure<20Gy.Esophageal exposure ?15Gy.Heart exposure ?10Gy.The three dimensional conformal treatment planning system calculated and confirmed set-up reference points.was used for radiotherapy.4.Follow-up and statistics analysisThe follow-up methods include out patient service and telephone interview.The patients were followed up for 3 to 51 months after treatment.CT scans were reviewed every 3 months.The degree of lung injury was determined by RTOG grading standard.And the statistics methods include SPSS 17.0 for statistical analysis.Kaplan Meier method for survival analysis,Log-rank test to compare the survival of the differences between two groups,Cox multiple factors regression analysis for independent prognostic factors.[Results]Part ? the results of 20 patients who accepted I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)1.Clinical features and therapeutic evaluationAll 20 cases consists of 16 males and 4 females.10 age?60 and 10 age<60.4 patients were I stage(T1N0M0),16 patients were ? stage(T2N0M0).Local control rate(ORR)was 90%,16 patients were completely recession(CR)and 4 patients were partial recession(PR).2.Survival outcomes4 patients were die and 16 patients were survive,2 patients were die within year.One year survival rates was 90%.3.Indicators of radioactive pneumonia(V20,V30)I125seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)group V20 and V30 were 6.06%.4.207%.Part ? the research results of Stereotactic ablative radiotherapy(SBRT)1.Clinical features and therapeutic evaluationAll 10 cases consists of 7 males and 3 females.7 age?60 and 3 age<60,2 patients were ? stage(T1N0M0),8 patients were ? stage(T2N0M0).Local control rate(ORR)was 80%,6 patients were completely recession(CR)and 2 patients were partial recession(PR).2.Survival outcomes3 patients were die and 7 patients were survive,1 patients were die within year.One year survival rates was 90%.3.Indicators of radioactive pneumonia(V20,V30)Stereotactic ablative radiotherapy(SBRT)group V20 and V30 were 11.32%?7.111%.[Conclusion]1.Local control rate(ORR):I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3 DCRT)group and Stereotactic ablative radiotherapy(SBRT)group ORR were 90%and 80%respectively.There was no statistically significant difference between the two groups(P=0.76).2.One year survival rates:I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)group and Stereotactic ablative radiotherapy(SBRT)group ORR were 90%and 90%respectively.There was no statistically significant difference between the two groups(P=1.00).3.Indicators of radioactive pneumonia(V20,V30):I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)group and Stereotactic ablative radiotherapy(SBRT)group ORR were 6.06%?4.207%and 11.32%?7.111%respectively.It's statistically significant,between the two groups.(P=0.000024,0.00090 respectively).4.Adverse reactions and complications:Among the 20 patients in group A,6 cases(30%)had pneumothorax occurred in I125 seeds particle implantation,4 of which were not treated with special treatment,and 2 cases were treated with closed thoracic drainage.4 cases(20%)were expectorated with hematopoietic phlegm.After 1-2 days treated by anti-inflammatory cough and hemostatic drugs,the symptoms were disappeared.During 3DCRT,2 cases(10%)patients experienced degrees ? cough and expectoration,and cured after treatment with anti-inflammatory.No above degrees ? adverse reactions.In group B,4 cases(40%)appeared degree ? adverse reactions.Among them,3 cases were cough chest tightness,1 case was chest pain,and cured after treatment.[Research significance and outlook]Lots of studies have explored the efficacy and safety of I125 seeds brachytherapy(RSB)implantation for non-small cell lung cancer,and the preliminary results are satisfactory.However,there are few studies on the treatment of non-small cell lung cancer by I125 seeds brachytherapy(RSB)particle implantation.This research applied the I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)plus Stereotactic ablative radiotherapy(SBRT)in early non-small cell lung cancer.The local control and one year survival rate of two groups were similar.The group with I125 seeds brachytherapy(RSB)joint 3Dconformal radiotherapy(3DCRT)showed a significant lower indicators of radioactive pneumonia(V20.V30)than group Stereotactic ablative radiotherapy(SBRT).This suggested that I125seeds brachytherapy(RSB)joint 3D-conformal radiotherapy(3DCRT)can significantly reduce the incidence of radiation pneumonia.However,due to fewer cases and shorter follow-up time,the optimal combination dose and the most appropriate interval for internal and external irradiation are still to be further studied.