Pickles T, Goodman G B, Rheaume D E, Duncan G G, Fryer C J, Bhimji S, Ludgate C, Syndikus I, Graham P, Dimitrov M, Bowen J
British Columbia Cancer Agency, Vancouver, Canada.
Int J Radiat Oncol Biol Phys. 1997 Feb 1;37(3):491-7. doi: 10.1016/s0360-3016(96)00542-1.
This study attempted to compare within a randomized study the outcome of pion radiation therapy vs. conventional photon irradiation for the treatment of high-grade astrocytomas.
Eighty-four patients were randomized to pion therapy (33-34.5 Gy pi), or conventional photon irradiation (60 Gy). Entry criteria included astrocytoma (modified Kernohan high Grade 3 or Grade 4), age 18-70, Karnofsky performance status (KPS) > or = 50, ability to start irradiation within 30 days of surgery, unifocal tumor, and treatment volume < 850 cc. The high-dose volume in both arms was computed tomography enhancement plus a 2-cm margin. The study was designed with the power to detect a twofold difference between arms.
Eighty-one eligible patients were equally balanced for all known prognostic variables. Pion patients started radiation 7 days earlier on average than photon patients, but other treatment-related variables did not differ. There were no significant differences for either early or late radiation toxicity between treatment arms. Actuarial survival analysis shows no differences in terms of time to local recurrence or overall survival where median survival was 10 months in both arms (p = 0.22). The physician-assessed KPS and patient-assessed quality of life (QOL) measurements were generally maintained within 10 percentage points until shortly before tumor recurrence. There was no apparent difference in the serial KPS or QOL scores between treatment arms.
In contrast to high linear energy transfer (LET) therapy for central nervous system tumors, such as neutron or neon therapy, the safety of pion therapy, which is of intermediate LET, has been reaffirmed. However, this study has demonstrated no therapeutic gain for pion therapy of glioblastoma.
本研究试图在一项随机研究中比较π介子放射治疗与传统光子照射治疗高级别星形细胞瘤的疗效。
84例患者被随机分为π介子治疗组（33 - 34.5 Gy π介子）或传统光子照射组（60 Gy）。入选标准包括星形细胞瘤（改良Kernohan 3级或4级）、年龄18 - 70岁、卡氏功能状态（KPS）≥50、能在术后30天内开始照射、肿瘤单灶、治疗体积<850 cc。两组的高剂量体积均为计算机断层扫描增强区域加2厘米边界。该研究设计的检验效能足以检测两组之间的两倍差异。
81例符合条件的患者在所有已知预后变量方面均衡良好。π介子治疗组患者开始放疗的时间平均比光子治疗组早7天，但其他与治疗相关的变量无差异。治疗组之间在早期或晚期放射毒性方面均无显著差异。精算生存分析显示，在局部复发时间或总生存方面无差异，两组的中位生存时间均为10个月（p = 0.22）。医生评估的KPS和患者评估的生活质量（QOL）测量值通常在肿瘤复发前不久一直保持在10个百分点以内。治疗组之间的连续KPS或QOL评分无明显差异。
与用于中枢神经系统肿瘤的高传能线密度（LET）治疗，如中子或氖治疗不同，中等LET的π介子治疗的安全性已得到再次确认。然而，本研究表明π介子治疗胶质母细胞瘤并无治疗获益。
