Linstadt D E, Castro J R, Phillips T L
Department of Radiation Oncology, University of California, San Francisco.
Int J Radiat Oncol Biol Phys. 1991 Apr;20(4):761-9. doi: 10.1016/0360-3016(91)90020-5.
Neon ion radiotherapy possesses biologic and physical advantages over megavoltage X rays. Biologically, the neon beam reduces the oxygen enhancement ratio and increases relative biological effectiveness. Cells irradiated by neon ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical behavior of heavy charged particles allows precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. In 1979 a Phase I-II clinical trial was started at Lawrence Berkeley Laboratory using neon ions to irradiate patients for whom conventional treatment modalities were ineffective. By the end of 1988 a total of 239 patients had received a minimum neon physical dose of 1000 cGy (median follow-up for survivors 32 months). Compared with historical results, the 5-year actuarial disease-specific survival (DSS5) and local control (LC5) rates suggest that neon treatment improves outcome for several types of tumors: a) advanced or recurrent macroscopic salivary gland carcinomas (DSS5 59%; LC5 61%); b) paranasal sinus tumors (DSS5 69%; LC5 69% for macroscopic disease); c) advanced soft tissue sarcomas (DSS5 56%, LC5 56% for macroscopic disease); d) macroscopic sarcomas of bone (DSS5 45%; LC5 59%); e) locally advanced prostate carcinomas (DSS5 90%; LC5 75%); and f) biliary tract carcinomas (DSS5 28%; LC5 44%). Treatment of malignant gliomas, pancreatic, gastric, esophageal, lung, and advanced or recurrent head and neck cancer has been less successful; results for these tumors appear no better than those achieved with conventional x-ray therapy. These findings suggest that Phase III trials using the neon beam should be implemented for selected malignancies.
与兆伏级X射线相比，氖离子放射治疗具有生物学和物理学优势。从生物学角度来看，氖离子束降低了氧增强比并提高了相对生物效应。受氖离子照射的细胞在细胞周期相关放射敏感性方面的变化较小，且辐射损伤的修复减少。重带电粒子的物理特性使得能够将高辐射剂量精确地传递到肿瘤部位，同时将对正常组织的照射降至最低。1979年，劳伦斯伯克利实验室启动了一项I-II期临床试验，使用氖离子对传统治疗方式无效的患者进行照射。到1988年底，共有239名患者接受了至少1000 cGy的氖物理剂量（幸存者的中位随访时间为32个月）。与历史结果相比，5年精算疾病特异性生存率（DSS5）和局部控制率（LC5）表明，氖离子治疗可改善几种类型肿瘤的治疗效果：a）晚期或复发性肉眼可见的涎腺癌（DSS5 59%；LC5 61%）；b）鼻窦肿瘤（DSS5 69%；肉眼可见疾病的LC5 69%）；c）晚期软组织肉瘤（DSS5 56%，肉眼可见疾病的LC5 56%）；d）肉眼可见的骨肉瘤（DSS5 45%；LC5 59%）；e）局部晚期前列腺癌（DSS5 90%；LC5 75%）；f）胆管癌（DSS5 28%；LC5 44%）。恶性胶质瘤、胰腺癌、胃癌、食管癌、肺癌以及晚期或复发性头颈癌的治疗效果较差；这些肿瘤的治疗结果似乎并不比传统X射线治疗更好。这些发现表明，应针对特定恶性肿瘤开展使用氖离子束的III期试验。
