大分割三维适形放疗在非小细胞肺癌治疗中的应用  

Three-dimensional conformal hypofractionated radiotherapy for non-small-cell lung cancer

作　　者：谢松喜[1] 李伟雄[1] 林映如[1] 邹文长[1] 

机构地区：[1]广东省人民医院肿瘤中心放疗科,广东广州510080

出　　处：《中国癌症杂志》2006年第12期1034-1037,共4页China Oncology

摘　　要：背景与目的：采用常规分割放射治疗治疗非小细胞肺癌其局部控制率较低，在适形放疔技术下可以采用大分割放疗，有望提高其局部控制率，但合适的分割剂量和毒性还需要深入研究。本研究前瞻性评估采用大分割三维适形放疗治疗非小细胞肺癌的安全性和有效性。方法：根据剂量体积直方图V20（受到20Gy以上照射的肺的体积占全肺体积的比例）水平将患者分成3组治疗：①低V20组（V20≤20％组），②中V20组（20％〈V20〈30％组），③高V20组（V20≥30％组），每5例患者为一组依次进入上述3个V20水平进行试验，放疗方法为三维适形放疔，每次3Gy，总剂量57～66Gy，4～5周完成。最大耐受剂量定义为10例患者中有至少有8例患者能耐受剂量限制毒性（≥Ⅲ级的放射性损伤）。放射毒性分级采用美国肿瘤放射治疗协作组（RTOG）早期和晚期损伤标准。所有患者不进行同期放化疔。结果：低V20组，共10例患者完成试验，无≥HI级的放射性肺炎发生；中V20组，先5例患者中有1例发生Ⅲ级放射性肺炎，再增加5例患者后无发生≥Ⅲ级的放射性肺炎；高V20组，5例患者中有2例发生Ⅲ级放射性肺炎，1例发生Ⅳ级放射性肺炎而死亡。没有≥Ⅲ级的放射性食管炎：25例患者中有8例达到完全缓解（32％），13例达到部分缓解（52％）．3例稳定（12％），1例进展（4％）。结论：进行大分割三维适形放疗时，把V20控制在30％以下是可行的，当V20≥30％时应改为姑息性放疗。其有效性需要进一步研究。Background and purpose： The local tumor control rate of non-small-cell lung cancer treated with conventionally fractionated radiotherapy is low, Hypofractionated radiotherapy performed by conformal irradiation techniques can improne the local control rate. But further studies for appropriate fraction dose and toxicity for hypofractionation should be done. The purpose of this study was to prospectively evaluate the safety and efficacy of three-dimensional eonformal hypofractionated radiotherapy for non-small-cell lung cancer（NSCLC）. Methods： According to the dose-volume histogram （DVH） V20, patients were divided into three groups： ① V20≤420%, ②20%〈 V20 〈 30% , ③V20≥30%, respectively. Each group contained five patients and were treated according to V20 level, three-dimensional conformal radiotherapy was delivered at 3 Gy/fraction once daily to a total dose of 57-66 Gy in 4-5 weeks. The maximum tolerated dose（MTD） was defined as the dose that more than 8 of 10 patients could tolerate the dose-llmiting toxicity（DLT） （ grade/〉 Ⅲ radiation injuries）. Radiation toxicity was graded according to the RTOG Acute and Late Morbidity Scoring Criteria. Results： Ten patients were enrolled at V20 ≤〈20% level, no grade≥Ⅲ radiation pneumonitis（RP） was observed; grade m RP was observed in 1 of 5 initial patients in the group with 20% 〈 V20〈 30% level, but not observed in 5 additional patients, In group with V20 〉 30%, grade Ⅲ RP was observes in 2 of 5 patients and grade Ⅳ RP in 1 patient who died of lung function failure. No grade ≥Ⅲ radiation esophagltis was observed . 25 patients were evaluated with 8 complete responses, 13 partial responses, 3 stable diseases and 1 progressive disease. Conclusions： For three-dimensional conformal hypofractionated radiotherapy V20 level should be controlled below 30%, the treatment plan with V20 930% should be changed to palliative treatment. More studies are needed to confirm its efficacy.

关 键 词：非小细胞肺癌 大分割适形放射疗法 剂量体积直方图 

分 类 号：R734.2[医药卫生—肿瘤] R730.55[医药卫生—临床医学]