47例鼻咽癌外照射配合咽旁间隙插植后装治疗的研究

The Studies on External Irradiation Combined with After-loading Therapy by Implantation in Parapharygeal Space on Nasopharyngeal Carcinoma:A Report of 47 Cases

目的:探讨外照射配合咽旁间隙插植治疗鼻咽癌的价值。方法:初治的鼻咽癌患者常规行外照射68～70Gy后复查CT或MRI,有咽旁间隙残留的98例,随机分成2组。一组行咽旁间隙插植后装补量(插植组),共47例。插植的方法是在模拟定位机引导下,经颌下插入1～3根施源管至咽旁区。后装机采用核通公司生产的192Ir高剂量率近距离治疗机,补量12～15Gy/4～6次/2～3d(2次/d,2.5～4Gy/次,每次间隔>6h);另一组行耳后野补量12～14Gy(对照组),共51例。结果:插植组与对照组3年总生存率及3年无远处转移生存率,差异无显著意义(P>0.05);3年无局部复发生存率,插植组显著高于对照组(P<0.05);晚期放射反应中的口干及张口受限等,插植组显著低于对照组(P<0.05)。结论:做为鼻咽癌咽旁间隙的补量,咽旁间隙插植后装治疗可显著提高咽旁间隙区残留的局部控制率,且晚期放射反应显著低于耳后野补量照射,具有较理想的临床应用价值。

Objective： To evaluate the role of external beam radiation combined with interstitial brachytherapy for nasopharyngeal carcinoma. Methods： Ninety-eight cases with nasopharyngeal carcinoma had residual lesion left in the parapharygeal space, as confirmed by CT or MRI after a standard dose of 68-70Gy with conventional external irradiation. They were divided into two groups randomly. One with 47 cases （PSIBT group） received interstitial brachytherapy to give a boost complement. With 1-3 implanted catheters, an additional boost of 12-15Gy/6-8 fractions/2-3 days was completed by after-loading of high dose rate ^192Ir wires. The other group （51 cases） received an additional dose of 12- 14Gy with external beam radiotherapy as control. Results： There were no statistical significance （P〉 0.05） in the overall 3-year survival rates and the 3-year distant metastasis-free survivals for two groups. The 3-year local relapse-free survival of PSIBT group was higher than that of control group （P〈 0.05）. And in the PSIBT group, the chronic sequelae, such as xerostomia, decreased hearing, trismus etc, happened less than that of the control group significantly （P〈0.05）. Conclusions： As the boost for nasopharyngeal cancer at parapharyngeal space, the inserted after-loading therapy can obviously enhanced the local control rate for residues in the parapharyngeal space, and the effect of irradiation on tumors of advanced stage is significantly lower compared to boost complement at post aurem field, with a relatively ideal value of clinical application.