颅内生殖细胞瘤适形调强放射治疗及剂量学研究

Conformal intensity modulated radiation therapy for intracranial germinoma and related dosimetry

目的应用半野和适形调强全脑全脊髓放射治疗技术治疗颅内生殖细胞瘤,评价其疗效及毒性反应。方法 12例颅内生殖细胞瘤患者,其中男性10例,女性2例;年龄15～28岁,中位年龄21岁。给予CT模拟定位,采用半野和适形调强放射治疗技术治疗,全脑全脊髓的放射治疗剂量为25.2 Gy(14次),肿瘤病灶的放射治疗总剂量为45 Gy(25次),每天每次1.8 Gy,5次/周,治疗后及随后每3个月评价1次疗效,随访时间为1～60个月,中位随访时间36个月。结果放射治疗结束后评价,完全缓解11例,部分缓解1例,近期临床受益率为100%。除1例失访外,其余11例均生存。放射治疗剂量学研究:经适形调强优化后的技术剂量分布优于常规定位技术,定位时间明显缩短[(8.83±1.55)s vs(40.8±2.4)s]。结论半野技术结合适形调强放射治疗技术治疗颅内生殖细胞瘤,优化了放射治疗剂量学,操作方便,疗效好,并发症少。

Objective To evaluate the efficacy and toxicity of the half-field and intensity modulated radiation therapy technology for the therapy of intracranial germinoma.Methods A total of 12 patients with intracranial germinoma were enrolled,male 10,female 2,aged 15-28 years old,median age 21 years old.All of them were treated by half-field and intensity modulated radiation therapy.The radiation dose of whole brain and whole spinal cord was 25.2 Gy/14 fractions,and total dose of tumor lesions was 45 Gy/25 fractions,1.8 Gy/（fraction·day）,5 days/week.The efficacy in end of treatment and every 3 months were evaluated.The total followed-up time was 1-60 months.Results The results after treatment showed that 11 cases were complete response,1 case was partial response,and the recent clinic benefit rate was 100 %.Except 1 patient was lost,the remaining 11 cases were survival.The study of radiation dose showed that intensity modulated radiation therapy technology was superior to conventional technologies and positioning time was significantly shorten[（8.83 ± 1.55） seconds vs（40.8 ± 2.4） seconds].Conclusion It is demonstrated that the half-field and intensity modulated radiation therapy technology could optimize the radiation dosimetry,operate easily,and obtain better efficacy and fewer complications in the treatment of intracranial germinoma.