Suppl Morten Hiul
Dan Med J. 2018 Apr;65(4).
Metastatic spinal cord compression is caused by the progression of metastatic lesions within the vicinity of the spinal cord. The consequences are very severe with loss of neurological function and severe pain. The standard treatment is surgical intervention followed by radiotherapy or radiotherapy alone. However, the majority of patients are treated with radiotherapy only due to contraindications to surgery and technical inoperability. Stereotactic body radiotherapy is a technology to deliver higher radiation dose to the radiotherapy target with the use of spatial coordinates. This modality has shown positive results in treating lesions in brain and lungs. Hence, it could prove beneficial in metastatic spinal cord compression. We designed and planned a trial to investigate this method in patients with metastatic spinal cord compression. The method was usable but the trial was stopped prematurely due to low accrual that made comparison with surgery impossible. Low accrual is a known problem for trials evaluating new approaches in radiotherapy. Target definition in radiotherapy of metastatic spinal cord compression is defined by patient history, examination and imaging. Functional imaging could provide information to guide target definition with the sparring of normal tissue e.g. spinal cord and hematopoietic tissue of the bone marrow. In future trials this may be used for dose escalation of spinal metastases. The trial showed that PET/MRI was feasible in this group of patients but did not change the radiotherapy target in the included patients. Neurological outcome is similar irrespective of course length and therefore single fraction radiotherapy is recommended for the majority of patients. In-field recurrence is a risk factor of both short and long fractionation schemes and re-irradiation have the potential risk of radiation-induced myelopathy. In a retrospective study of re-irradiation, we investigated the incidence of radiation-induced myelopathy. In our study population, we found a higher number of patients experiencing vertebral fractures than the number of patient developing myelopathy. Patients with diabetes had an increased risk of toxicity compared to the remaining patients. Stereotactic body radiotherapy is effective in treating metastatic spinal cord compression but the efficacy cannot be determined due low accrual. The use of PET/MRI did not spare normal tissue in radiotherapy planning of spinal metastases. The incidence of toxicity after re-irradiation of the spine and spinal cord was low. For patients with in-field recurrence, re-irradiation is safe and has a low incidence of toxicity.
转移性脊髓压迫是由脊髓附近转移性病变的进展引起的。其后果非常严重，会导致神经功能丧失和剧烈疼痛。标准治疗方法是手术干预，随后进行放疗或仅进行放疗。然而，由于手术禁忌症和技术上的不可操作性，大多数患者仅接受放疗。立体定向体部放疗是一种利用空间坐标向放疗靶区给予更高辐射剂量的技术。这种方式在治疗脑和肺部病变方面已显示出积极效果。因此，它可能对转移性脊髓压迫有益。我们设计并计划了一项试验，以研究这种方法在转移性脊髓压迫患者中的应用。该方法可行，但由于入组率低，无法与手术进行比较，试验提前终止。入组率低是评估放疗新方法试验中一个已知的问题。转移性脊髓压迫放疗中的靶区定义由患者病史、检查和影像学确定。功能成像可以提供信息，以指导靶区定义，同时保护正常组织，如脊髓和骨髓的造血组织。在未来的试验中，这可能用于脊柱转移瘤的剂量递增。该试验表明，PET/MRI在这组患者中是可行的，但并未改变纳入患者的放疗靶区。无论疗程长短，神经学结果相似，因此建议大多数患者采用单次分割放疗。野内复发是短程和长程分割方案的危险因素，再次放疗有辐射性脊髓病的潜在风险。在一项关于再次放疗的回顾性研究中，我们调查了辐射性脊髓病的发生率。在我们的研究人群中，我们发现发生椎体骨折的患者数量多于发生脊髓病的患者数量。与其余患者相比，糖尿病患者的毒性风险增加。立体定向体部放疗在治疗转移性脊髓压迫方面有效，但由于入组率低，疗效无法确定。在脊柱转移瘤的放疗计划中，PET/MRI的使用并未保护正常组织。脊柱和脊髓再次放疗后的毒性发生率较低。对于野内复发的患者，再次放疗是安全的，毒性发生率较低。
