Radiotherapy For Spinal Metastases Research Articles

Long Term Changes in Normal Vertebral Bone Density after Radiation Therapy

Bone density is the universal measure of bone strength and integrity. Insufficiency fractures are reported after radiation therapy. The cause is uncertain, but conceptually, radiation alters the integrity of the bone. We measure bone density before and after radiation therapy of normal vertebra to test for significant change. A total of 36 patients were identified who received photon radiation therapy for spinal metastases to a field including an adjacent vertebra without an identifiable lesion with at least a year of follow up. The irradiated normal bone received a mean total dose of 28.14 Gy (range 8 – 45 Gy) and mean BED of 57.4 Gy (range 29-90 Gy). Mean follow-up imaging intervals between pre-treatment and follow-up scans was 14.5 months (range 2.3 – 34 months). Every patient had an untreated vertebra of similar type available as a control. A Hounsfield-density calibration curve was used to measure the vertebral body density before and after treatment. The region of measurement included the trabecular bone and 1/3 of the inner cortical bone to avoid bias while capturing changes in cortical bone. Sample normality was confirmed with the Shapiro-Wilk test, and a paired t-test was used to compare pre-radiation and post-radiation densities. A p < 0.05 was used to establish significance. The density of the irradiated normal bone did not significantly decrease in control or irradiated vertebra. The Shapiro-Wilk test confirmed normality with pre-treatment p = 0.057 and post-treatment p = 0.175. Control vertebra had a mean density change of -0.10% (95% CI = 0.73, p = 0.74). Irradiated bone had a mean density change if -0.94% (95% CI = 1.06, p = 0.09). We found no significant change in bone density after irradiation of normal bone, suggesting that architectural integrity is maintained. Further work is needed to elucidate more complex causes of insufficiency fractures after radiation.

The Role of Minimal Access Surgery in the Treatment of Spinal Metastatic Tumors.

Study Design:Literature review.Objective:To provide an overview of the recent advances in minimal access surgery (MAS) for spinal metastases.Methods:Literature review.Results:Experience gained from MAS in the trauma, degenerative and deformity settings has paved the road for MAS techniques for spinal cancer. Current MAS techniques for the treatment of spinal metastases include percutaneous instrumentation, mini-open approaches for decompression and tumor resection with or without tubular/expandable retractors and thoracoscopy/endoscopy. Cancer care requires a multidisciplinary effort and adherence to treatment algorithms facilitates decision making, ultimately improving patient outcomes. Specific algorithms exist to help guide decisions for MAS for extradural spinal metastases. One major paradigm shift has been the implementation of percutaneous stabilization for treatment of neoplastic spinal instability. Percutaneous stabilization can be enhanced with cement augmentation for increased durability and pain palliation. Unlike osteoporotic fractures, kyphoplasty and vertebroplasty are known to be effective therapies for symptomatic pathologic compression fractures as supported by high level evidence. The integration of systemic body radiation therapy for spinal metastases has eliminated the need for aggressive tumor resection allowing implementation of MAS epidural tumor decompression via tubular or expandable retractors and preliminary data exist regarding laser interstitial thermal therapy and radiofrequency ablation for tumor control. Neuronavigation and robotic systems offer increased precision, facilitating the role of MAS for spinal metastases.Conclusions:MAS has a significant role in the treatment of spinal metastases. This review highlights the current utilization of minimally invasive surgical strategies for treatment of spinal metastases.

Advantages of Radiation Therapy Simulation with 0.35 Tesla Magnetic Resonance Imaging for Stereotactic Ablation of Spinal Metastases

The hybrid 0.35T magnetic resonance imaging (MRI) and radiation therapy system functions in part as a simulation platform for treatment planning. We have found that the images generated are particularly helpful for planning of stereotactic radiation therapy for spinal metastases. Advantages include the following: (1) Low-field MRI mitigates magnetic susceptibility artifacts caused by spinal hardware. (2) Volumetric pulse sequence provides isotropic images for improved target delineation. (3) Wide-bore MRI in the radiation oncology department allows for easy simulation in treatment position for accurate fusion across imaging modalities. (4) When patients are treated on the MRI and radiation therapy hybrid device, adaptive radiation therapy is available for special situations to avoid mobile organs at risk.

Time-Driven, Activity-Based Cost Analysis of Radiation Treatment Options for Spinal Metastases.

Several treatment options for spinal metastases exist, including multiple radiation therapy (RT) techniques: three-dimensional (3D) conventional RT (3D-RT), intensity-modulated RT (IMRT), and spine stereotactic radiosurgery (SSRS). Although data exist regarding reimbursement differences across regimens, differences in provider care delivery costs have yet to be evaluated. We quantified institutional costs associated with RT for spinal metastases, using a time-driven activity-based costing model. Comparisons were made between (1) 10-fraction 3D-RT to 30 Gy, (2) 10-fraction IMRT to 30 Gy, (3) 3-fraction SSRS (SSRS-3) to 27 Gy, and (4) single-fraction SSRS (SSRS-1) to 18 Gy. Process maps were developed from consultation through follow-up 30 days post-treatment. Process times were determined through panel interviews, and personnel costs were extracted from institutional salary data. The capacity cost rate was determined for each resource, then multiplied by activity time to calculate costs, which were summed to determine total cost. Full-cycle costs of SSRS-1 were 17% lower and 17% higher compared with IMRT and 3D-RT, respectively. Full-cycle costs for SSRS-3 were only 1% greater than 10-fraction IMRT. Technical costs for IMRT were 50% and 77% more than SSRS-3 and SSRS-1. In contrast, personnel costs were 3% and 28% higher for SSRS-1 than IMRT and 3D-RT, respectively (P < .001). Resource utilization varies significantly among treatment options. By quantifying provider care delivery costs, this analysis supports the institutional resource efficiency of SSRS-1. Incorporating clinical outcomes with such resource and cost data will provide additional insight into the highest value modalities and may inform alternative payment models, operational workflows, and institutional resource allocation.

Feasibility and preliminary clinical results of linac-based Stereotactic Body Radiotherapy for spinal metastases using a dedicated contouring and planning system

BackgroundStereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT) are well established local treatment approaches in several cancer settings. Although SBRT is still under investigation for spinal metastases, promising results in terms of a high effectiveness and optimal tolerability have been recently published on this topic. For spinal SBRT, one of the most relevant issues is represented by the inter-observer variability in target definition. Recently, several technological innovations, including specific tools such as multimodality-imaging (computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET-CT), automated volumes contouring and planning, could allow clinicians to minimize the uncertainties related to spinal SBRT workflow. Aim of this study is to report the feasibility of the clinical application of a dedicated software (Element®, Brainlab™ Germany) for spinal metastases SBRT.Material and methodThe patient selection criteria for SBRT in spinal metastases were the following: age > 18 years, diagnosis of spinal metastases (n ≤ 3), life expectancy > 3 months, controlled primary tumor or synchronous diagnosis and Spinal Instability Neoplastic Score (SINS) ≤ 12 points. All radiation target volumes were defined and planned with the support of the dedicated software Elements® (Brainlab™ Germany). Different dose prescription have been used: 12 Gy in single fraction, 12 Gy, 18 Gy, 21 Gy and 24 Gy in 3 fractions. Toxicity was assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.0. SPSS version 20 was used for statistical analysis.ResultsFrom April 2018 to April 2019, 54 spinal metastases in 32 recruited patients were treated with Linac-based SBRT. With a median follow-up of 6 months (range 3–12), local control rates at 6 months and 9 months were 86 and 86%, respectively. No adverse events ≥3 grade were observed.ConclusionsThis preliminary experience shows that with respect to acute toxicity and early clinical response, linac-based using Elements® Spine SRS is a feasible and effective approach.

Patient satisfaction with treatment outcomes after surgery and/or radiotherapy for spinal metastases

BackgroundPatient satisfaction is infrequently investigated despite its importance in assessing efficacy and patient comprehension. The purpose of this study was to investigate patient satisfaction with treatment outcomes after surgery and/or radiotherapy for spinal metastases and to evaluate how health‐related quality of life (HRQOL) is related to patient satisfaction.MethodsPatients with spinal metastases treated with surgery and/or radiotherapy were enrolled in a prospective, international, observational study. Demographic, histologic, treatment, and HRQOL data were collected. HRQOL was evaluated with the Numeric Rating Scale pain score, the 3‐level version of the EuroQol 5‐Dimension (EQ‐5D‐3L) instrument, and the Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0). Patient satisfaction was derived from the SOSGOQ2.0 at 6, 12, and 26 weeks after treatment. Patients were classified as satisfied, neutral, or dissatisfied.ResultsTwelve weeks after treatment, 183 of the surgically treated patients (84%) were satisfied, and only 11 (5%) were dissatisfied; in contrast, 101 of the patients treated with radiotherapy alone (77%) were satisfied, and only 7 (5%) were dissatisfied. Significant improvements in pain, physical function, mental health, social function, leg function, and EQ‐5D were associated with satisfaction after surgery. Satisfaction after radiotherapy was associated with significant improvements in pain, mental health, and overall SOSGOQ2.0 scores. Dissatisfaction after treatment was associated with lower baseline values for leg strength and lower social functioning scores for surgically treated patients and with lower social functioning scores and being single for patients treated with radiotherapy.ConclusionsHigh levels of satisfaction with treatment outcomes are observed after surgery and/or radiotherapy for spinal metastases. Posttreatment satisfaction is associated with significant improvements in pain and different dimensions of HRQOL.

Prognostic evaluation of patients with metastatic spinal tumors using modified Tokuhashi's score: A retrospective study

Introduction: Tokuhashi's scoring has been used as a presurgical tool for prediction of survival in patients with spinal metastases (SM). It evaluates prognostic factors such as performance status, number of extraspinal bone metastasis, metastasis to visceral organs, site of primary, and neurological status that determine the survival in these patients. To the best of our knowledge, only limited studies are available to use this scoring system to determine survival outcomes in patients with SMs undergoing palliative radiotherapy. Aim: The purpose of our study was to determine the patient characteristics and usefulness of modified Tokuhashi's score in determining survival in patients with SM. Methods: This is a retrospective study of patients who underwent radiotherapy for SM from January 2013 to December 2017. Results: Seventy patients with SM from solid tumors were included in the study. The male to female ratio was 1.3:1. The median ageat diagnosis of SM was 50 years. The median survival was 7 months. The modified Tokuhashi's score ranged from 0 to 13, and the mean score was 6. In our study, 46 belonged to the poor prognostic group, 20 belonged to the moderate prognostic group, and 4 patients belongedto good prognostic group with a median survival of 4.8, 13.5, and 28 months, respectively. There was a statistical significance in the difference in survival in three prognostic groups. Conclusion: Our study confirms the usefulness of modified Tokuhashi's score in determining the survival outcomes in patients with metastatic spinal tumors.

Radiofrequency Ablation and Radiation Therapy Improve Local Control in Spinal Metastases Compared to Radiofrequency Ablation Alone.

The spinal column is the most common location for osseous metastases and is associated with pain and decreased quality of life. This study evaluated combined radiofrequency ablation (RFA) with radiation therapy (RT) compared to RFA alone for improving pain and local control. This was a single-institution retrospective review of patients who underwent RFA of spinal metastases between 2016 and 2017, with or without RT to the same vertebral level. Pain was measured with visual analog scale at initial presentation and at 3 and 12 weeks of follow-up. Local failure (LF), distant failure, and overall survival (OS) were compared and Kaplan-Meier statistics were calculated. Twenty-six patients with 28 spinal metastases were treated with RFA. Ten patients with 11 metastases were treated with RFA + RT. More patients with lung primaries were treated with RFA alone and more patients with breast primaries were treated with combination RFA+RT. There was no significant difference in pain scores between groups ( P = .96). At a median follow-up of 8.2 months, LF was noted in 8 of 17 metastases treated with RFA alone compared to 1 of 11 metastases treated with RFA+RT ( P = .049). There was a significant benefit in time to LF favoring RFA+RT ( P = .02) and a significant benefit in OS ( P = .0045). This study demonstrates a benefit in local control with RFA+RT versus RFA alone. Palliation of pain was effective using both regimens. This study was limited by a nearly unequal distribution of primary tumor histologies between groups. Literature regarding combined treatment of RFA and RT for spinal metastases is scarce and prospective protocols are warranted.

Stereotactic Body Radiation Therapy for Spinal Metastases; Clinical Experience in 134 Cases from a Single Japanese Institution

This study aimed to clarify the outcomes of stereotactic body radiotherapy (SBRT) for spinal metastases in our institution. Patients treated with spine SBRT were retrospectively reviewed from a prospective database. The prescribed dose was 24 Gy in 2 fractions. Endpoints were local control, pain control, and adverse events. Local control was defined as elimination, shrinkage, or no change in tumor on computed tomography or magnetic resonance imaging. Pain status was measured on a scale of 0-10 by patient's self-reports, and pain response was defined as the time at which pain scale score decreased by more than 2 from the baseline score without increase in analgesics. In addition, various treatment- and tumor-specific factors were evaluated to determine predictive values for local and pain control. This study included 134 lesions in 131 patients, with: histology of primary disease, lung/colorectal/thyroid/renal/breast/prostate/sarcoma/other cancer, 24/22/18/14/12/10/6/25; re-irradiation SBRT, 82 cases (61.2%); and postoperative SBRT for epidural spinal cord compression, 45 cases (33.6%). Median follow-up after SBRT was 9 months (range, 1-50 months). The 1-year local control rate was 72.3%. Seventy of the 88 cases (79.5%) with pain from spinal metastases achieved pain response after SBRT. The 1-year pain progression-free rate was 61.7%. Regarding colorectal metastases, local and pain control rates at 1 year were significantly lower compared with other cancer types (local control rate, 33.8% vs. 75.4%, p<0.01; pain progression-free rate, 36.9% vs. 70.2%, p=0.04). On multivariate analysis, colorectal metastases and radiation history were identified as independent predictors of lower local and pain control rates. Radiation-induced myelopathy, radiculopathy and vertebral compression fractures were observed in 0, 2 (1.5%) and 16 (11.9%) cases, respectively. No other grade 3 or greater toxicities were encountered. The present study showed that spine SBRT achieved good local and pain control, and a clinically acceptable safety profile. However, SBRT may be less effective against colorectal metastases.Abstract TU_15_3037; Table 1Characteristics (Number of cases)1-y radiographic local control rateUnivariate P valueMultivariate analysisP valueHR95% CIKarnofsky PS 80+ (105) <80 (26)73.9% 64.3%0.27NANANAHistopathology Colorectal (22) Thyroid (20) Renal cell (14) Sarcoma (6) Melanoma (0) Other (72)34.1% 80.8% 88.9% Not reached No Data 82.5%<0.01*<0.01*3.911.77 to 8.64Systemic disease Controlled (71) Active (63)75.6% 68.3%0.48NANANANumber of spinal levels 1 (61) 2 (24) 3 or more (31)72.9% 83.3% 67%0.70NANANARadiation history Radiation naïve (52) Prior spine radiation (81)84.7% 61.6%0.02*0.04*0.420.18 to 0.95Surgical decompression - (89) + (45)71.4% 73.3%0.57NANANABilsky grade at SBRT 0/I (98) II/III (36)77.5% 60.6%0.28NANANA Open table in a new tab

Stereotactic Body Radiation Therapy in Nonsurgical Patients with Metastatic Spinal Disease and Epidural Compression: A Retrospective Review

In the setting of spinal metastases with epidural cord compression, radiosurgery is often only considered when there is sufficient separation between the epidural disease and the spinal cord. However, in patients who are nonsurgical candidates or those who prefer nonoperative management, there may be a benefit from stereotactic body radiation therapy, even when the epidural target is closer than the traditionally referenced 3 mm distance from the spinal cord. The purpose of this retrospective study is to evaluate our institution's experience in treating 20 such patients. We reviewed records of all patients treated with stereotactic body radiation therapy for spinal metastases at our institution from January 2010 to January 2016, with follow-up through December 2016. The primary end point was local progression of disease. Local progression was defined as clear radiographic disease growth on follow-up imaging or worsening clinical symptoms in the absence of evidence for radiation myelopathy. Local control was obtained in 55% of patients meeting these criteria without a single case of radiation myelitis. Most patients with disease progression were able to undergo additional local treatment. Although local control was less than expected when compared with spine radiosurgery with adequate separation between the target and spinal cord, this treatment appears to be a viable option in the nonsurgical candidate.

Effectiveness of Positron Emission Tomography/Computed Tomography as a Guide for Palliative Radiation Therapy for Spinal Metastases

As back pain is the presenting symptom in 95% of patients with epidural spinal metastases, appropriately identifying and treating the most symptomatic levels can provide significant palliation. The purpose of this study was to analyze the ability of combined positron emission tomography (PET)/computed tomography (CT) to identify spinal metastases with high metabolic activity and guide radiotherapy. We sought to correlate improvement in back pain with reduction in standard uptake value (SUV) after treatment. Retrospective review was performed of 72 patients with spinal metastases treated with stereotactic ablative radiation therapy at a single center between 2002 and 2014. PET/CT was used to calculate SUVs for spinal metastases, and treatment planning was based on PET/CT results. Preoperative and postoperative pain levels were assessed in all patients. Reduction in pain scores was found in 78% of treated patients. A significant reduction in pain was identified in patients with >5 metastases compared with fewer lesions (P < 0.05). Degree of change in SUV did not correlate significantly with pain relief. However, comparing pretreatment and posttreatment PET/CT, patients with improved pain consistently displayed decreased SUV. PET/CT was shown to be a useful adjunct in radiation treatment planning with change in SUV correlating with symptomatic improvement. This study paves the way for future prospective studies to further assess utility and cost-effectiveness of this imaging modality in radiation treatment planning for spinal metastases.

Early Tissue Effects of Stereotactic Body Radiation Therapy for Spinal Metastases

Stereotactic body radiation therapy (SBRT) is a highly effective and potentially ablative treatment for complex spinal metastases. Recent data have suggested radiobiologic effects of SBRT that expand beyond the traditional concept of DNA damage. Antitumor immunity, vascular damage leading to tumor necrosis, and increased rates of tumor apoptosis have been implied; however, in-human evidence remains scarce. The present study reports unique pathologic confirmation of SBRT-induced biological effects within spinal metastases treated with preoperative SBRT. Ten patients with spinal metastases secondary to various solid tumors were treated with preoperative single-fraction SBRT (18Gy) to the magnetic resonance imaging-defined macroscopic metastasis, followed by spinal stabilization within 24hours. Perioperative samples of spinal metastases were obtained, and 6 patients also had a pre-SBRT biopsy specimen available for a matched comparison. The samples were stained for tumor necrosis on routine hematoxylin-eosin-stained slices and, subsequently, immunohistochemical staining for T cells (CD3+, CD4+, CD8+), natural killer cells (CD56+), endothelium (CD31+), and apoptotic activity (caspase-3). Perioperative biopsy specimens were obtained ∼6hours (range 4.5-7.5) or 21hours (range 18.5-22.5) after SBRT. Necrosis was observed in 83% of the 21-hour post-SBRT samples (5 of 6) compared with 0% of pre-SBRT biopsies (0 of 6) and 6-hour post-SBRT biopsies (0 of 4). Tumor cell apoptosis had increased greatly in the 21-hour post-SBRT samples compared with before and 6hours after SBRT. The CD31+vessel counts decreased after SBRT, as did mitotic activity. Both of the renal cell metastases displayed major decreases in vessel density. Desmoplastic reaction was visible in 67% (4 of 6) of the pre-SBRT samples compared with 100% (10 of 10) the post-SBRT samples. The T-cell and natural killer cell counts were relatively unaffected. High-dose single-fraction SBRT induced tumor necrosis, desmoplasia, and tumor apoptosis and decreased tumor vessel density within 24hours, even in renal cell metastases. The role of immune cells seems limited in this early phase. These first-in-human results imply direct vascular and DNA damage mechanisms important in the clinical efficacy specific to spinal SBRT.

Assessing the utility of a prognostication model to predict 1-year mortality in patients undergoing radiation therapy for spinal metastases

Background ContextPredicting survival outcomes after radiation therapy (RT) alone for metastatic disease of the spine is a challenging task that is important to guiding treatment decisions (eg, determining dose fractionation and intensity). The New England Spinal Metastasis Score (NESMS) was recently introduced and validated in independent cohorts as a tool to predict 1-year survival following surgery for spinal metastases. This metric is composed of three factors: preoperative albumin, ambulatory status, and modified Bauer score, with the total score ranging from 0 to 3. PurposeThe purpose of this study was to assess the applicability of the NESMS model to predict 1-year survival among patients treated with RT alone for spinal metastases. Study Design/SettingThis study is a retrospective analysis. Patient SampleThis sample included 290 patients who underwent conventional RT alone for spinal metastases. Outcome MeasuresPatients' NESMS (composed of ambulatory status, pretreatment serum albumin, and modified Bauer score) were assessed, as well as their 1-year overall survival rates following radiation for metastatic disease of the spine. Materials and MethodsThis study is a single-institution retrospective analysis of 290 patients treated with conventional radiation alone for spinal metastases from 2008 to 2013. The predictive value of the NESMS was assessed using multivariable logistic regression modeling, adjusted for potential confounding variables. ResultsThis analysis indicated that patients with lower NESMSs had higher rates of 1-year mortality. Multivariable analysis demonstrated a strong association between lower NESMSs and lower rates of survival. ConclusionsThe NESMS is a simple prognostic scheme that requires clinical data that are often readily available and have been validated in independent cohorts of surgical patients. This study serves to validate the utility of the NESMS composite score to predict 1-year mortality in patients treated with radiation alone for spinal metastases.

Assessing the Utility of the Spinal Instability in Neoplasia Score to Predict Fracture after Conventional Radiation Therapy for Spinal Metastases

Assessing the Utility of the Spinal Instability in Neoplasia Score to Predict Fracture after Conventional Radiation Therapy for Spinal Metastases

Assessing the Utility of a Prognostication Model to Predict 1-Year Mortality in Patients Receiving Radiation Therapy for Spinal Metastases

Assessing the Utility of a Prognostication Model to Predict 1-Year Mortality in Patients Receiving Radiation Therapy for Spinal Metastases

Reirradiation spine stereotactic body radiation therapy for spinal metastases: systematic review.

OBJECTIVE Spinal metastases that recur after conventional palliative radiotherapy have historically been difficult to manage due to concerns of spinal cord toxicity in the retreatment setting. Spine stereotactic body radiation therapy (SBRT), also known as stereotactic radiosurgery, is emerging as an effective and safe means of delivering ablative doses to these recurrent tumors. The authors performed a systematic review of the literature to determine the clinical efficacy and safety of spine SBRT specific to previously irradiated spinal metastases. METHODS A systematic literature review was conducted, which was specific to SBRT to the spine, using MEDLINE, Embase, Cochrane Evidence-Based Medicine Database, National Guideline Clearinghouse, and CMA Infobase, with further bibliographic review of appropriate articles. Research questions included: 1) Is retreatment spine SBRT efficacious with respect to local control and symptom control? 2) Is retreatment spine SBRT safe? RESULTS The initial literature search retrieved 2263 articles. Of these articles, 160 were potentially relevant, 105 were selected for in-depth review, and 9 studies met all inclusion criteria for analysis. All studies were single-institution series, including 4 retrospective, 3 retrospective series of prospective databases, 1 prospective, and 1 Phase I/II prospective study (low- or very low-quality data). The results indicated that spine SBRT is effective, with a median 1-year local control rate of 76% (range 66%-90%). Improvement in patients' pain scores post-SBRT ranged from 65% to 81%. Treatment delivery was safe, with crude rates of vertebral body fracture of 12% (range 0%-22%) and radiation-induced myelopathy of 1.2%. CONCLUSIONS This systematic literature review suggests that SBRT to previously irradiated spinal metastases is safe and effective with respect to both local control and pain relief. Although the evidence is limited to low-quality data, SBRT can be a recommended treatment option for reirradiation.

Delayed Epidural Mucin Collection after Surgery for Spinal Metastatic Pancreatic Adenocarcinoma.

A rare case of delayed large epidural mucin collection causing neurologic deficit after surgery for metastatic pancreatic cancer is reported. A 65-year-old man presented with intractable upper-thoracic back pain radiating to the chest and gait disturbance. He had a history of subtotal pancreatectomy due to intraductal papillary mucinous neoplasm (IPMN) of the pancreas and concurrent chemotherapy. Eight months after pancreatectomy, multiple thoracic spinal metastasis was diagnosed with routine up positron emission tomography-computed tomography. Radiotherapy for spinal metastasis and subsequent chemotherapy was carried out. Sixteen months after pancreatectomy, gait disturbance occurred and follow-up thoracic magnetic resonance imaging (MRI) showed aggravation of metastasis at T2 and T4 compressing the spinal cord. We performed a decompressive laminectomy with subtotal resection of the tumor masses and pedicle screw fixation at C7–T6. Neurologic status improved after the operation. Histopathologic examinations revealed the tumor as metastatic mucin producing adenocarcinoma. Three months after surgery, motor weakness and pain was reappeared. MRI showed large amount of epidural fluid collection. We performed wound revision and there was large amount of gelatinous fluid at the epidural space. We suggest that postoperative mucin collection and wound problems should be considered after surgery for mucin producing metastatic pancreatic tumor.

Consensus guidelines for postoperative stereotactic body radiation therapy for spinal metastases: results of an international survey.

OBJECTIVE Although postoperative stereotactic body radiation therapy (SBRT) for spinal metastases is increasingly performed, few guidelines exist for this application. The purpose of this study is to develop consensus guidelines to promote safe and effective treatment for patients with spinal metastases. METHODS Fifteen radiation oncologists and 5 neurosurgeons, representing 19 centers in 4 countries and having a collective experience of more than 1300 postoperative spine SBRT cases, completed a 19-question survey about postoperative spine SBRT practice. Responses were defined as follows: 1) consensus: selected by ≥ 75% of respondents; 2) predominant: selected by 50% of respondents or more; and 3) controversial: no single response selected by a majority of respondents. RESULTS Consensus treatment indications included: radioresistant primary, 1-2 levels of adjacent disease, and previous radiation therapy. Contraindications included: involvement of more than 3 contiguous vertebral bodies, ASIA Grade A status (complete spinal cord injury without preservation of motor or sensory function), and postoperative Bilsky Grade 3 residual (cord compression without any CSF around the cord). For treatment planning, co-registration of the preoperative MRI and postoperative T1-weighted MRI (with or without gadolinium) and delineation of the cord on the T2-weighted MRI (and/or CT myelogram in cases of significant hardware artifact) were predominant. Consensus GTV (gross tumor volume) was the postoperative residual tumor based on MRI. Predominant CTV (clinical tumor volume) practice was to include the postoperative bed defined as the entire extent of preoperative tumor, the relevant anatomical compartment and any residual disease. Consensus was achieved with respect to not including the surgical hardware and incision in the CTV. PTV (planning tumor volume) expansion was controversial, ranging from 0 to 2 mm. The spinal cord avoidance structure was predominantly the true cord. Circumferential treatment of the epidural space and margin for paraspinal extension was controversial. Prescription doses and spinal cord tolerances based on clinical scenario, neurological compromise, and prior overlapping treatments were controversial, but reasonable ranges are presented. Fifty percent of those surveyed practiced an integrated boost to areas of residual tumor and density override for hardware within the beam path. Acceptable PTV coverage was controversial, but consensus was achieved with respect to compromising coverage to meet cord constraint and fractionation to improve coverage while meeting cord constraint. CONCLUSIONS The consensus by spinal radiosurgery experts suggests that postoperative SBRT is indicated for radioresistant primary lesions, disease confined to 1-2 vertebral levels, and/or prior overlapping radiotherapy. The GTV is the postoperative residual tumor, and the CTV is the postoperative bed defined as the entire extent of preoperative tumor and anatomical compartment plus residual disease. Hardware and scar do not need to be included in CTV. While predominant agreement was reached about treatment planning and definition of organs at risk, future investigation will be critical in better understanding areas of controversy, including whether circumferential treatment of the epidural space is necessary, management of paraspinal extension, and the optimal dose fractionation schedules.

PO-0777: Evaluation of spinal stability in relation to pain response after radiotherapy for spinal metastases

PO-0777: Evaluation of spinal stability in relation to pain response after radiotherapy for spinal metastases

Stereotactic Body Radiation Therapy for Spinal Metastases in the Postoperative Setting: A Secondary Analysis of Mature Phase 1-2 Trials

To evaluate the outcomes in patients treated on prospective phase 1-2 protocols with postoperative stereotactic body radiation therapy (SBRT) and identify the associated prognostic variables. Sixty-six patients with 69 tumors were treated with SBRT on prospective phase 1-2 studies for spinal metastases between 2002 and 2010. All patients underwent SBRT after spine surgery, which included laminectomy, vertebrectomy, or a combination of these techniques. Renal cell carcinoma was the most common histology represented (n=35, 53%) followed by sarcomas (n=13, 20%). Thirty-one patients (47%) were treated with prior conventional radiation to the spine (median dose 30Gy). Patients were followed up with spinal magnetic resonance imaging (MRI) studies to determine the treated tumor control (TC). Pain and other symptom data were collected prospectively to determine treatment response and toxicity. The median follow-up time was 30months (range, 1-145months) for all patients and 75months for living patients (range, 6-145months). The actuarial 1-year rate of TC was 85%, adjacent vertebral body control was 85%, and overall survival (OS) was 74% (median 29months). On multivariate competing-risks analysis, sarcoma histology (subhazard ratio [SHR]=2.38, 95% confidence interval [CI] 1.05-5.6, P=.04) and larger preoperative tumor volumes (SHR=1.01, 95% CI 1.0-1.01, P=.006) were significantly associated with worse TC. Karnofsky performance status was the only significant predictor for OS on multivariate analysis. There were no differences in TC between patients treated with different surgical techniques or different preoperative or postoperative Bilsky grades. There were no grade 3 or higher neurologic toxicities. This study represents a large series of prospective data available on patients treated with SBRT in the postoperative setting. The combination of surgery with SBRT can offer patients with metastatic disease to the spine the chance of durable tumor control with minimal toxicity.