头颈部复发癌^(125)I粒子植入治疗剂量学评估与临床观察

Dosimetric verification of ^(125)I seed implantation in recurrent head and neck cancer and the result of clinical efficacy

目的:研究125I粒子植入治疗头颈部复发癌术前和术后计划的剂量学差异及其对临床疗效的影响。方法:将河北省人民医院25例头颈部晚期复发肿瘤患者在CT或B超引导下植入125I粒子治疗。术前采用治疗计划系统(TPS)重建肿瘤三维立体图象,计算125I粒子植入的数目、空间分布和剂量分布。计划靶区匹配周边剂量(MPD)为85～120Gy,术后1周内做验证计划,比较术前以及术后80%、90%、100%肿瘤体积接受的处方剂量(D80、D90、D100)、计划靶区接受90%、100%、150%处方剂量的体积百分比(V90、V100、V150)、平均吸收剂量(Dmean)、计划靶区体积(PTV)各组数据差异,并观察疗效、局部控制率、生存期和术后并发症。结果:术前、术后D80、D90、D100、V150、Dmean和PTV差异无统计学意义,t值分别为0.79、1.95、0.89、0.59和-1.52,z=-0.66,P>0.05;V90、V100手术后较手术前明显降低,差异有统计学意义,t值分别为4.13.3.83,P<0.05。随访3～93个月,随访率96%。CR 5例,PR 14例,NC 4例,PD 2例,总有效率(CR+PR)为76%;3、6、12和24个月局部控制率分别为92%、76%、64%和28%。中位生存时间15个月。1和2年生存率分别为64%和52%。2例患者分别脱落6和5颗粒子;3例术后出现Ⅳ级皮肤损伤,经对症治疗后好转。4例出现Ⅰ级皮肤反应,3个月内好转。结论:125I粒子植入术后验证剂量,基本可以实现预期剂量分布,是一种较为安全、有效的治疗头颈部晚期复发肿瘤的方法。

OBJECTIVE:To research the dosimetric difference between the preimplantation plan and the postimplantation plan and to explore the actual effect of the difference to clinical efficacy.METHODS: Twenty-five patients with head and neck recurrent malignant tumor were treated with 125I seeds implantation under the guidance of B-ultrasonography or CT.The pre-plan was accomplished according to the TPS to reconstruct tumor three-dimensional image and to calculate the seed number,placement and dose distribution.MPD for planning target volume was 85-120 Gy,dosimetric verification was accomplished in one week after implantation.The difference of D80,D90,D100,V90,V100,V150,Dmean,PTV volume between preimplantation and postimplantation were compared.All the patients were evaluated with CT examinations after the treatment.The efficacy,the local control rate,survival time and complications after operation were observed.RESULTS: There were no difference in D80,D90,D100,V150,Dmean,PTV volume between preplan and postplan(t were 0.79,1.95,0.89,0.59 and-1.52,z=-0.66,P>0.05),but were difference in V90,V100(t were 4.13 and 3.83,P<0.05).The follow-up was 3-93 months and the follow-up rate was 96%.Complete remission(CR),partial remission(PR),no change(NC),and progress disease(PD) were seen in 5,14,4,and 2 patient respectively.The overall effective rate(CR+PR) was 76%.The 3-,6-month and 1-,2-year local control rates were 92%,76%,64%,28% respectively.The median survival time was 15 months. The 1-and 2-year survival rates were 64% and 52% respectively.Two cases fall 6 and 5 seeds respectively.3 cases had grade 4 skin injury and improved after symptomatic treatment.Four cases had grade 1 skin injury and improved within 3 months.CONCLUSIONS: Expected dosimetric distribution can be achieved basically according to dosimetric verification of 125I Seed implantation.125I seed implantation is a safe,effective method in the treatment of recurrent head and neck cancer.