CAJ | 학술논문

目的：研究非小细胞肺癌（NSCLC）放疗过程中再次CT 定位及相应放疗计划修改对肿瘤区及正常组织剂量学影响。方法对53例经病理证实的NSCLC患者放疗过程中进行再次定位，根据肿瘤及肺体积变化，修改放疗计划，通过拟合两次计划，分析叠加的剂量体积参数，与不修改的放疗计划的剂量体积参数比较。结果放疗计划修改前照射次数为（20.0±4.2）次，计划修改后G T V缩小了（71.98±34.6） cm3，且 G T V 变化与计划修改前照射次数呈正相关关系，r＝0.497，P＝0.006。最初设计的总计划与再次C T设计的计划拟合后患侧肺和全肺的平均受量分别下降了（4.6±10.1）％、（4.1±8.7）％，P值分别为0.03和0.02。拟合叠加计划与初次总的计划比较，心脏的V30受照射剂量下降了（2.68±1.3）％，脊髓的Dmax下降了（12.4±2.8）％。结论三维适形放疗中肿瘤体积发生退缩，可以适时地修改放疗计划以减少正常组织的受照射剂量，从而可以推量照射以提高肿瘤的受照射剂量。
목적：연구비소세포폐암（NSCLC）방료과정중재차CT 정위급상응방료계화수개대종류구급정상조직제량학영향。방법대53례경병리증실적NSCLC환자방료과정중진행재차정위，근거종류급폐체적변화，수개방료계화，통과의합량차계화，분석첩가적제량체적삼수，여불수개적방료계화적제량체적삼수비교。결과방료계화수개전조사차수위（20.0±4.2）차，계화수개후G T V축소료（71.98±34.6） cm3，차 G T V 변화여계화수개전조사차수정정상관관계，r＝0.497，P＝0.006。최초설계적총계화여재차C T설계적계화의합후환측폐화전폐적평균수량분별하강료（4.6±10.1）％、（4.1±8.7）％，P치분별위0.03화0.02。의합첩가계화여초차총적계화비교，심장적V30수조사제량하강료（2.68±1.3）％，척수적Dmax하강료（12.4±2.8）％。결론삼유괄형방료중종류체적발생퇴축，가이괄시지수개방료계화이감소정상조직적수조사제량，종이가이추량조사이제고종류적수조사제량。
Objective To study the change of target volume during radiotherapy for non‐small cell lung cancer (NSCLC) and the inference of treatment plan changing for normal tissue .Methods Fifty‐three NSCLC patients were treated with 3D‐CRT scanned by CT repeatedly and treatment plan changed according to the tumor and lung volume change .Results Totally patients with (20.0+ 4.2) irradiation fractions before treatment plan changing .The GTV shrinkaged (71.98 ± 34.6) and the change of GTV was positively correlated with irradiation fractions before radiotherapy plan changing(r=0.497 ,P=0.006) .Mean lung dose of ipsilateral and all lung descended (4.6 ± 10.1) and (4.1 ± 8.7) ,compared with the first plan .V30 irradiated dose dropped (2.68+1.3)% and the Dmax of spinal cord descended (12.4 +2.8)% .Conclusion Primary tumor volume changed constantly during 3D‐CRT ,we can duly modify radiotherapy plan to reduce the exposure dose of normal tissue ,which could im‐prove the irra diated dose of the tumor .