Dose Fusion And Curative Effect Evaluation Of Different Doses Of Radical Radiotherapy For Cervical Cancer

Background:In less developed countries,cervical cancer is the second most common cancer and the third leading cause of cancer death among women.Treatment of cervical cancer include surgery,radiation therapy and chemotherapy and other methods,given the development of different treatment options based on different stages.For patients with locally advanced cervical cancer,concurrent chemoradiotherapy is the standard treatment option.Radiation therapy includes external beam radiation and brachytherapy.External beam radiation has gradually evolved from traditional two-dimensional radiotherapy(2D-CRT)to three-dimensional conformal radiotherapy(3D-CRT),intensity-modulated radiotherapy(IMRT),etc.,which are mainly targeted at pelvic metastasis regions,such as parauterine tissue,paracervix tissue and lymph node drainage area;Brachytherapy,also known as afterloading,includes intracavitary and brachytherapy(ICBT),Interstitial brachytherapy(ISBT),and intracavitary and interstitial combined brachytherapy(IC / ISBT),and has gradually developed from two-dimensional brachytherapy to three-dimensional brachytherapy,mainly targeting the primary tumor area.For patients with cervical cancer undergoing radical radiotherapy,the total external radiation dose is mostly 45Gy(40-50Gy),and the segmentation method is1.8-2.0Gy / fraction.For residual lymph nodes,an additional 10-15 Gy can be given.In clinical practice,both external beam radiation doses of 45 Gy and 50.4Gy are used,and there is no uniform standard.Objective:Analysis of the dosimetric differences between patients with different external radiation doses and CT guided intracavitary and interstitial combinedthree-dimensional brachytherapy,by external radiation and brachytherapy dose fusion technology,and evaluation of treatment efficacy and quality of life of patients with cervical cancer.Methods:We selected 79 patients with cervical cancer who underwent radical radiotherapy and divided them into two groups according to different external radiation doses.We combined the external radiation with three-dimensional brachytherapy dose to analyze the dosimetric differences and Response Evaluation Criteria in Solid Tumors(RECIST)used to evaluate the efficacy of the treatment.Evaluate the curative effect of the treatment,evaluate the adverse reactions according to the Common Terminology Criteria for Adverse Events CTCAE4.03,and evaluate the quality of life of the patients after treatment with the quality of life questionnaire(QLQ-C30).Results:There was no significant difference in the target CTVD90 of the fusion dose between the 45 Gy group and the 50.4Gy group,but the rectal D2 cc and bladder D2 cc in the 45 Gy group were lower than those in the 50.4Gy group(P <0.05).In terms of external irradiation,the rectal D2 cc and bladder in the 45 Gy group D2 cc is lower than50.4Gy(P <0.05);in terms of brachytherapy,there is no significant difference between rectal D2 cc and bladder D2 cc between the two groups(P> 0.05),suggesting that the difference in bladder and rectal doses between the two groups mainly comes from external irradiation.None of the follow-up patients had grade 3-4 toxicity.There was no statistical difference between the two groups of patients in the recent evaluation of efficacy and adverse reactions(P> 0.05).There was no significant difference in the functional and symptomatic areas in the quality of life assessment between the two groups of patients(P> 0.05),but in the area of overall health,the45 Gy group was higher than the 50.4Gy group(P <0.05).Conclusion:External beam radiation combined with CT-guided intracavitary and interstitial combined brachytherapy technology for the treatment of cervical cancer.When selecting the dose of external irradiation,moderately reducing the external irradiationdose does not affect the total target dose and therapeutic effect of the patient,and can also reduce the radiation dose of the surrounding normal organs.Dose fusion technology can be used to fully evaluate the patient's external radiation and post-treatment therapeutic fusion dose during the treatment process.When the dose is found to be insufficient,timely supplementation should be given.At the same time,the surrounding organ-restricted dose should be paid attention to,and the patient's quality of life after treatment.