DeLaney Thomas F, Liebsch Norbert J, Pedlow Francis X, Adams Judith, Dean Susan, Yeap Beow Y, McManus Patricia, Rosenberg Andrew E, Nielsen G Petur, Harmon David C, Spiro Ira J, Raskin Kevin A, Suit Herman D, Yoon Sam S, Hornicek Francis J
Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
Int J Radiat Oncol Biol Phys. 2009 Jul 1;74(3):732-9. doi: 10.1016/j.ijrobp.2008.08.058. Epub 2008 Dec 25.
Radiotherapy (XRT) for spine sarcomas is constrained by spinal cord, nerve, and viscera tolerance. Negative surgical margins are uncommon; hence, doses of >or=66 Gy are recommended. A Phase II clinical trial evaluated high-dose photon/proton XRT for spine sarcomas.
Eligible patients had nonmetastatic, thoracic, lumbar, and/or sacral spine/paraspinal sarcomas. Treatment included pre- and/or postoperative photon/proton XRT with or without radical resection; patients with osteosarcoma and Ewing's sarcoma received chemotherapy. Shrinking fields delivered 50.4 cobalt Gray equivalent (Gy RBE) to subclinical disease, 70.2 Gy RBE to microscopic disease in the tumor bed, and 77.4 Gy RBE to gross disease at 1.8 Gy RBE qd. Doses were reduced for radiosensitive histologies, concurrent chemoradiation, or when diabetes or autoimmune disease present. Spinal cord dose was limited to 63/54 Gy RBE to surface/center. Intraoperative boost doses of 7.5 to 10 Gy could be given by dural plaque.
A total of 50 patients (29 chordoma, 14 chondrosarcoma, 7 other) underwent gross total (n = 25) or subtotal (n = 12) resection or biopsy (n = 13). With 48 month median follow-up, 5-year actuarial local control, recurrence-free survival, and overall survival are: 78%, 63%, and 87% respectively. Two of 36 (5.6%) patients treated for primary versus 7/14 (50%) for recurrent tumor developed local recurrence (p < 0.001). Five patients developed late radiation-associated complications; no myelopathy developed but three sacral neuropathies appeared after 77.12 to 77.4 Gy RBE.
Local control with this treatment is high in patients radiated at the time of primary presentation. Spinal cord dose constraints appear to be safe. Sacral nerves receiving 77.12-77.4 Gy RBE are at risk for late toxicity.
脊柱肉瘤的放射治疗（XRT）受脊髓、神经和内脏耐受性的限制。手术切缘阴性并不常见；因此，推荐剂量≥66 Gy。一项II期临床试验评估了高剂量光子/质子XRT治疗脊柱肉瘤的效果。
符合条件的患者患有非转移性胸段、腰段和/或骶段脊柱/脊柱旁肉瘤。治疗包括术前和/或术后光子/质子XRT，可联合或不联合根治性切除术；骨肉瘤和尤因肉瘤患者接受化疗。缩野照射给予亚临床病灶50.4钴 Gray等效剂量（Gy RBE）、肿瘤床微小病灶70.2 Gy RBE以及大体病灶77.4 Gy RBE，剂量率为1.8 Gy RBE每天。对于放射敏感组织学类型、同步放化疗或存在糖尿病或自身免疫性疾病的患者，剂量降低。脊髓剂量限制在表面/中心63/54 Gy RBE。术中可通过硬脑膜斑块给予7.5至10 Gy的追加剂量。
共有50例患者（29例脊索瘤、14例软骨肉瘤、7例其他）接受了根治性（n = 25）或次全切除（n = 12）或活检（n = 13）。中位随访48个月，5年精算局部控制率、无复发生存率和总生存率分别为78%、63%和87%。36例原发性肿瘤患者中有2例（5.6%）出现局部复发，而14例复发性肿瘤患者中有7例（50%）出现局部复发（p < 0.001）。5例患者出现晚期放疗相关并发症；未发生脊髓病，但3例骶神经病变在77.12至77.4 Gy RBE后出现。
初次就诊时接受放疗的患者局部控制率较高。脊髓剂量限制似乎是安全的。接受77.12 - 77.4 Gy RBE的骶神经有发生晚期毒性的风险。
