MRI-guided stereotactic ablative radiation therapy of spinal bone metastases: a preliminary experience.
- 作者列表："Llorente R","Spieler BO","Victoria J","Takita C","Yechieli R","Ford JC","Brown K","Samuels MA","Mellon EA
OBJECTIVE:MRI provides clear visualization of spinal cord, tumor, and bone for patient positioning and verification during MRI-guided radiotherapy (MRI-RT). Therefore, we wished to evaluate spine stereotactic ablative radiotherapy (SABR) feasibility with MRI-RT. Given dosimetric limitations of first generation Co-60 MRI-RT, we then evaluated improvements by newer linear accelerator (linac) MRI-RT. METHODS:Nine spinal metastases were treated with Co-60 MRI-RT. Seven received a single 16 Gy fraction, and two received three fractions totaling 24 or 30 Gy. After replanning with linac MRI-RT software, comparisons of organ at risk and dose spillage objectives between Co-60 and linac plans were performed. RESULTS:Spinal cord and cauda equina dose constraints were met in all Co-60 cases. Treatments were delivered successfully with real-time imaging during treatment and no treatment-related toxicities. While limits for dose spillage into surrounding soft tissues were not achieved due to the limitations of the Co-60 system, this could be corrected with linac MRI-RT delivery. CONCLUSIONS:MRI-RT SABR of spinal metastases is feasible with Co-60 MRI-RT. Dose delivery is improved by linac MRI-RT. ADVANCES IN KNOWLEDGE:This is the first report of MRI-RT for SABR of spinal metastases. The enhanced visualization of anatomy by MRI may facilitate RT dose escalation for spine SABR.
目的: MRI为MRI引导放疗 (MRI-RT) 期间的患者定位和验证提供脊髓、肿瘤和骨骼的清晰可视化。因此，我们希望用MRI-RT评价脊柱立体定向消融放疗 (SABR) 的可行性。鉴于第一代Co-60 MRI-RT的剂量限制，我们随后评估了较新的直线加速器 (linac) MRI-RT的改进。 方法: 对 9 例脊柱转移瘤进行Co-60 MRI-RT治疗。7 人获得单一 16 Gy分数，2 人获得 3 个分数总计 24 或 30 Gy。在使用linac MRI-RT软件重新计划后，比较Co-60 和linac计划之间的器官风险和剂量溢出目标。 结果: Co-60 病例均符合脊髓和马尾神经剂量限制。治疗过程中实时成像成功，无治疗相关毒性。虽然由于Co-60 系统的局限性，没有达到对周围软组织剂量溢出的限制，但这可以通过linac MRI-RT递送来纠正。 结论: MRI-RT-SABR诊断脊柱转移瘤是可行的，Co-60 MRI-RT。剂量输送通过直线加速器MRI-RT改善。 知识进展: 这是MRI-RT治疗脊柱转移瘤SABR的首次报告。MRI增强的解剖可视化可能有助于脊柱SABR的RT剂量递增。
METHODS:OBJECTIVE:Large inoperable sacral chordomas show unsatisfactory local control rates even when treated with high dose proton therapy (PT). The aim of this study is assessing feasibility and reporting early results of patients treated with PT and concomitant hyperthermia (HT). METHODS: :Patients had histologically proven unresectable sacral chordomas and received 70 Gy (relative biological effectiveness) in 2.5 Gy fractions with concomitant weekly HT. Toxicity was assessed according to CTCAE_v4. A volumetric tumor response analysis was performed. RESULTS: :Five patients were treated with the combined approach. Median baseline tumor volume was 735 cc (range, 369-1142). All patients completed PT and received a median of 5 HT sessions (range, 2-6). Median follow-up was 18 months (range, 9-26). The volumetric analysis showed an objective response of all tumors (median shrinkage 46%; range, 9-72). All patients experienced acute Grade 2-3 local pain. One patient presented with a late Grade 3 iliac fracture. CONCLUSION:Combining PT and HT in large inoperable sacral chordomas is feasible and causes acceptable toxicity. Volumetric analysis shows promising early results, warranting confirmation in the framework of a prospective trial. ADVANCES IN KNOWLEDGE: :This is an encouraging first report of the feasibility and early results of concomitant HT and PT in treating inoperable sacral chordoma.
METHODS:BACKGROUND:National guidelines recommend screening and treatment for cancer-related bone disease and continued monitoring of bone-modifying agents. It is unclear whether a standardized screening tool is utilized to identify eligible patients and ensure appropriate supportive care is implemented. The purpose of this study was to evaluate current prescribing practices and optimize management of bone-modifying agents. METHODS:A retrospective chart review was performed to identify patients who received hormone deprivation therapy or had bone metastases through Hematology/Oncology or Urology clinics from 1 November 2016 to 31 October 2017. The primary endpoints of this study were the incidence of completed baseline dual-energy X-ray absorptiometry (DEXA) scan for patients on hormone deprivation therapy and percent of patients started on a bone-modifying agent for the prevention of skeletal-related events secondary to bone metastasis. Secondary endpoints included percent of patients with dental examinations prior to initiation, adequate calcium and vitamin D supplementation, incidence of osteonecrosis of the jaw or flu-like symptoms and education, and percent of bisphosphonate doses appropriately adjusted based on renal function. RESULTS:A total of 375 patients were assessed for baseline DEXA scans and bone-modifying therapy. Of the 226 patients on hormone deprivation therapy, 111 (49%) patients were appropriately screened with a DEXA scan prior to initiation of hormone deprivation therapy. Among the 149 patients with bone metastases, only 94 (63.1%) patients were started on a bone-modifying agent. CONCLUSIONS:Opportunities have been identified to optimize management of patients with cancer-related bone disease. Implementation of standardized tools may increase the rate of appropriate screening and initiation of bone-modifying therapy when warranted.
METHODS:PURPOSE:Low skeletal muscle mass has been associated with poor prognosis in patients with advanced lung cancer. However, little is known about the relationship between skeletal muscle mass and overall survival in patients with bone metastases from lung cancer. The objective of the present study was to evaluate the prognostic value of low trunk muscle mass in predicting overall survival in these patients. METHODS:The data from 198 patients who were diagnosed with bone metastases from lung cancer from April 2009 to May 2017 were retrospectively reviewed. The areas of the psoas and paravertebral muscles were measured at the level of the third lumbar vertebra on computed tomography scans taken at the time nearest to the diagnosis of bone metastasis. Muscle area was evaluated for male and female cohorts separately using different cutoff points. Cox proportional hazards analysis was performed to evaluate the factors independently associated with overall survival. RESULTS:The overall survival of patients in the lowest quartile for psoas muscle area or paravertebral muscle area was significantly shorter than that of patients above the 25th percentile for muscle area (p < 0.001). Multivariate analyses showed that paravertebral muscle mass (hazard ratio, 1.73; 95% confidence interval, 1.17-2.56; p = 0.006), epidermal growth factor receptor-targeted therapy, and performance status were independent prognostic factors. CONCLUSIONS:Low paravertebral muscle mass was associated with shorter survival, independently of known prognostic factors.