Stereotactic radiosurgery for spinal metastases from renal cell carcinoma

Stereotactic body radiotherapy for treatment of spinal metastasis: A systematic review of the literature

Background

Advances in local and systemic therapies continue to improve overall survival for patients with cancer, increasing the incidence of spine metastases. Up to 15% of patients with solid tumors develop spinal metastases. Spinal metastases can be particularly devastating for quality of life given the potential pain, neurological deficits from spinal cord compression or cauda equina syndrome, spinal instability, and pathological fractures that may result. Stereotactic body radiotherapy (SBRT) with or without adding less invasive surgical techniques for stabilization or separation has gained favor. SBRT uses smaller, more precise treatment volumes, allowing for higher doses per fracture, thus increasing ablative abilities.

Methods

We conducted a systematic review using MEDLINE, Embase (Elsevier), and Web of Science to identify all articles investigating the effectiveness of SBRT in providing local disease control, pain control, and relief of spinal cord compression for patients with metastatic disease of the spine.

Results

The review yielded 84 articles that met inclusion criteria. The evidence indicates SBRT provides excellent local control and pain control for patients with spine metastesis, and this remains true for patients with spinal cord compression managed with surgical separation followed by postoperative spine SBRT.

Conclusion

While not all patients are appropriate candidates for SBRT, carefully considering appropriate frameworks that consider the patient's overall prognosis can guide a multidisciplinary team toward the patients who will benefit the most from this treatment modality.

Stereotactic Radiosurgery in Metastatic Spine Disease-A Systemic Review of the Literature

BACKGROUND

This study investigated the efficacy of stereotactic radiosurgery (SRS) in managing spinal metastasis. Traditionally, surgery was the primary approach, but SRS has emerged as a promising alternative.

OBJECTIVE

The study aims to evaluate the efficacy of stereotactic radiosurgery in the management of spinal metastasis in terms of local tumor control, patient survival, and quality of life, identifying both advantages and limitations of SRS.

METHODS

Through an extensive literature search in PubMed with cross-referencing, relevant full-text-available papers published between 2012 and 2022 in English or German were included. The search string used was "metastatic spine diseases AND SRS OR stereotactic radiosurgery".

RESULTS

There is growing evidence of SRS as a precise and effective treatment. SRS delivers high radiation doses while minimizing exposure to critical neural structures, offering benefits like pain relief, limited tumor growth, and a low complication rate, even for tumors resistant to traditional radiation therapies. SRS can be a primary treatment for certain metastatic cases, particularly those without spinal cord compression.

CONCLUSIONS

SRS appears to be a preferable option for oligometastasis and radioresistant lesions, assuming there are no contraindications. Further research is necessary to refine treatment protocols, determine optimal radiation dose and fractionation schemes, and assess the long-term effects of SRS on neural structures.

Stereotactic Body Radiation Therapy for Sacral Metastases: Deviation From Recommended Target Volume Delineation Increases the Risk of Local Failure

PURPOSE

Although spine stereotactic body radiation therapy (SBRT) is considered a standard of care in the mobile spine, mature evidence reporting outcomes specific to sacral metastases is lacking. Furthermore, there is a need to validate the existing sacral SBRT international consensus contouring guidelines to define the optimal contouring approach. We report mature rates of local failure (LF), adverse events, and the effect of contouring deviations in the largest experience to date specific to sacrum SBRT.

METHODS AND MATERIALS

Consecutive patients who underwent sacral SBRT from 2010 to 2021 were retrospectively reviewed. The primary endpoint was magnetic resonance imaging-based LF with a focus on adherence to target volume contouring recommendations. Secondary endpoints included vertebral compression fracture and neural toxicity.

RESULTS

Of the 215 sacrum segments treated in 112 patients, most received 30 Gy/4 fractions (51%), 24 Gy/2 fractions (31%), or 30 Gy/5 fractions (10%). Sixteen percent of segments were nonadherent to the consensus guideline with a more restricted target volume (undercontoured). The median follow-up was 21.4 months (range, 1.5-116.9 months). The cumulative incidence of LF at 1 and 2 years was 18.4% and 23.1%, respectively. In those with guideline adherent versus nonadherent contours, the LF rate at 1 year was 15.1% versus 31.4% and at 2 years 18.8% versus 40.0% (hazard ratio [HR], 2.5; 95% CI, 1.4-4.6; P = .003), respectively. On multivariable analysis, guideline nonadherence (HR, 2.4; 95% CI, 1.3-4.7; P = .008), radioresistant histology (HR, 2.4; 95% CI, 1.4-4.1; P < .001), and extraosseous extension (HR, 2.5; 95% CI, 1.3-4.7; P = .005) predicted for an increased risk of LF. The cumulative incidence of vertebral compression fracture was 7.1% at 1 year and 12.3% at 2 years. Seven patients (6.3%) developed peripheral nerve toxicity, of whom 4 had been previously radiated.

CONCLUSIONS

Sacral SBRT is associated with high efficacy rates and an acceptable toxicity profile. Adhering to consensus guidelines for target volume delineation is recommended to reduce the risk of LF.

The NOMS approach to metastatic tumors: Integrating new technologies to improve outcomes

Treatment paradigms for patients with spine metastases have evolved significantly over the past two decades. The most transformative change to these paradigms has been the integration of spinal stereotactic radiosurgery (sSRS). sSRS allows for the delivery of tumoricidal radiation doses with sparing of nearby organs at risk, particularly the spinal cord. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional external beam radiation therapy. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care by improving both local control and patient survival. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases and integrates these data into a decision framework, NOMS, which is based on four sentinel pillars of decision making in metastatic spine tumors: Neurological status, Oncologic tumor behavior, Mechanical stability, and Systemic disease burden and medical co-morbidities.

The NOMS approach to metastatic tumors: Integrating new technologies to improve outcomes

Treatment paradigms for patients with spine metastases have evolved significantly over the past two decades. The most transformative change to these paradigms has been the integration of spinal stereotactic radiosurgery (sSRS). sSRS allows for the delivery of tumoricidal radiation doses with sparing of nearby organs at risk, particularly the spinal cord. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional external beam radiation therapy. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care by improving both local control and patient survival. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases and integrates these data into a decision framework, NOMS, which is based on four sentinel pillars of decision making in metastatic spine tumors: neurological status, Oocologic tumor behavior, mechanical stability and systemic disease burden and medical co-morbidities.

The 100 Top-Cited Articles on Robotic Neurosurgery: A Bibliometric Analysis

BACKGROUND

Robotic neurosurgery is a rapidly advancing field with numerous applications in various subspecialties, including spine, functional, skull base, and cerebrovascular. This study aims to provide a comprehensive analysis of the most-cited articles on robotic neurosurgery.

METHODS

The Web of Science database was used to collect data, and bibliometric analysis was performed using VOSviewer and RStudio. Network analysis techniques such as co-occurrence, coauthorship, bibliographic coupling, and thematic mapping analyses were used to identify the top 100 most cited articles, major contributors, emerging trends, and noteworthy themes in the field.

RESULTS

The results showed that there has been a steady increase in the number of publications on robotic neurosurgery since 1991, with an exponential growth in the number of citations. The United States was the most common country of origin for articles, followed by Canada. The most productive authors in this field were Burton S.A. and Gerszten P.C., while the University of Pittsburgh was the most productive institution, and Neurosurgery was the most productive journal. Themes such as robotics, back pain, and prostate cancer, as well as trends in developing new technologies and improving the precision of surgical procedures, were identified.

CONCLUSIONS

This study provides a comprehensive analysis of the most-cited articles on robotic neurosurgery. The broad range of topics and techniques explored emphasize the importance of continued innovation and investigation. Ultimately, the study's findings provide valuable guidance for future research and contribute to advancing our understanding of this critical area of study.

Beyond the Knife in Renal Cell Carcinoma: A Systematic Review-To Ablate or Not to Ablate?

Intensified systemic therapy in metastatic renal cell carcinoma (mRCC) has led to improved patient outcomes. Patients commonly require local control of one or a few metastases. The aim was to evaluate metastasis-directed ablative therapies in extracranial mRCC. Two databases and one registry were searched, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach, for all prospective and matched-pair case-control mRCC studies of radiofrequency ablation (RFA), cryotherapy, microwave ablation (MWA), and stereotactic body radiotherapy (SBRT). Eighteen studies were identified. Fourteen investigated SBRT in 424 patients. Four thermal ablation studies were identified: two cryotherapy (56 patients) and two RFA studies (90 patients). The median participant number was 30 (range 12-69). The combined median follow-up was 17.3 months (range 8-52). Four SBRT studies reported local control (LC) at 12 months, median 84.4% (range 82.5-93). Seven studies (six SBRT and one cryotherapy) reported an LC rate of median 87% (79-100%). Median overall survival (OS) was reported in eight studies (five SBRT, two cryotherapy, and one RFA) with a median of 22.7 months (range 6.7-not reached). Median progression-free survival was reported in seven studies (five SBRT, one cryotherapy, and one RFA); the median was 9.3 months (range 3.0-22.7 months). Grade ≥ 3 toxicity ranged from 1.7% to 10%. SBRT has excellent local control outcomes and acceptable toxicity. Only four eligible thermal ablative studies were identified and could not be compared with SBRT. Translationally rich definitive studies are warranted.

State of the Art: Multidisciplinary Management of Oligometastatic Renal Cell Carcinoma

Oligometastatic renal cell carcinoma (OM-RCC) refers to patients who have limited (typically up to 5) metastatic lesions. Although management principles may overlap, OM-RCC is distinguishable from oligoprogressive RCC, which describes progression of disease to a limited number of sites while receiving systemic therapy. Cytoreductive nephrectomy and metastasectomy are common surgical considerations in OM-RCC, and indications are discussed in this review. It is evident that stereotactic ablative radiotherapy is effective in RCC and is being applied increasingly in the oligometastatic setting. Finally, we will review advances in systemic therapy and the role of active surveillance before the initiation of systemic therapy.

Stereotactic Body Radiotherapy for Kidney Cancer: Ready for Prime Time?

The standard treatment for renal cell carcinoma (RCC) is surgery. However, a number of patients will not be candidates for surgical treatment or will reject this therapeutic approach. Therefore, alternative approaches are required. Historically, radiotherapy has been considered an ineffective treatment for RCC due to the radioresistance of renal tumour cells to conventional fractionation and the increased rate of toxicity. Stereotactic body radiotherapy (SBRT) is a radiotherapy technique that provides a non-invasive ablative treatment with remarkable rates of local control in both primary tumours and metastases in several locations, with a low associated morbidity due to the highly conformal dose and the use of image-guided techniques. Current evidence shows that a higher dose per fraction, achieving a higher biological effective dose, can overcome the radioresistance of RCC cells. Therefore, SBRT, as well as the combination of SBRT and new emerging immune therapies, has a potential role in the local treatment of primary RCC and oligometastatic RCC patients.

Hybrid Therapy (Surgery and Radiosurgery) for the Treatment of Renal Cell Carcinoma Spinal Metastases

BACKGROUND

The management of spinal metastatic renal cell carcinoma (mRCC) is controversial regarding extent of resection and radiation dosing.

OBJECTIVE

To determine outcomes in patients treated with hybrid therapy (separation surgery plus adjuvant stereotactic body radiation therapy [SBRT]) for mRCC.

METHODS

A retrospective study of a prospectively collected cohort of patients undergoing hybrid therapy for mRCC between 2003 and 2017 was performed. SBRT was delivered as high-dose single-fraction, high-dose hypofractionated, or low-dose hypofractionated. Extent of disease, clinical and operative outcomes, and complications data were collected, and associations with overall survival (OS) and progression-free survival were determined.

RESULTS

Ninety patients with mRCC with high-grade epidural spinal cord compression (ESCC grades 2 and 3) were treated. Metastases were widespread, oligometastatic, and solitary in 56%, 33%, and 11% of patients, respectively. SBRT delivered was high-dose single-fraction, high-dose hypofractionated, and low-dose hypofractionated in 24%, 56%, and 20% of patients, respectively. The 1-yr cumulative incidence of major complications was 3.4% (95% confidence interval [CI]: 0.0%-7.2%). The median follow-up was 14.2 mo for the entire cohort and 38.3 mo for survivors. The 1-yr cumulative incidence of progression was 4.6% (95% CI: 0.2%-9.0%), which translates to a local control rate of 95.4% (95% CI: 91.0%-99.8%) 1 yr after surgery. The median OS for the cohort was 14.8 mo.

CONCLUSION

These data support the use of hybrid therapy as a safe and effective strategy for the treatment of renal cell spine metastases.

[Stereotactic body radiation therapy for spine bone oligometastatic disease]

Stereotactic radiotherapy is an ever more common technique, regardless of the location treated. However, spinal stereotactic radiotherapy requires a particular technicality in order to ensure its proper realization. There is now a large literature defining the type of imaging to be used, the dose to be delivered and the delineation of target volumes. This technique can achieve a significant local control and an interesting analgesic efficiency. However, its place in relation to conventional radiotherapy remains limited because it requires MRI imaging and a significantly longer patient management during the treatment fraction. In this context, it is currently mainly restricted to oligometastatic patients or for re-irradiations.

Global Research Trends in Robotic Applications in Spinal Medicine: A Systematic Bibliometric Analysis

OBJECTIVE

We systematically evaluated the global research trends in robotic application on the spine through bibliometric analysis and mapping knowledge domains.

METHODS

A systematic literature search was performed of the PubMed and Web of Science, including the Science Citation Index Expanded, databases. The number, countries, journals, and authors of the publications, total citations, average publication year, and institution sources were analyzed using Microsoft Excel, the Online Analysis Platform of Bibliometrics, and VOSviewer. The hotspots were analyzed and visualized using VOSviewer.

RESULTS

We identified a total of 2135 publications. The United States ranked first in the number of publications (n = 824; 38.63%) and frequency of citations (n = 29,075). Northwestern University had the highest number of publications (n = 67) and Harvard University the highest number of citations (n = 4198). The Journal of NeuroEngineering and Rehabilitation published the largest number of reports (n = 73), and the most frequently cited journal was Nature (n = 3844 citations). The research hotspots were divided into 3 categories analyzed by VOSviewer: rehabilitation, basic science, and surgery. According to the average publication year, the most recent hotspot was radiation exposure, and the earliest hotspot was radiosurgery.

CONCLUSIONS

The number of studies of robotic application on the spine has continued to increase. The United States was the greatest contributor to robotic applications on the spine. Robot-assisted rehabilitation for neurological and orthopedic lesions is still a major research hotspot. The range of robotic applications on the spine has expanded from assisted rehabilitation to assisted rehabilitation and surgery.

Stereotactic Ablative Radiation (SAbR) for Oligometastatic RCC

A significant proportion of metastatic renal cell carcinoma (mRCC) patients present with oligometastatic disease. Retrospective and limited prospective data suggests that a subgroup of patients with oligometastatic mRCC benefits from aggressive local therapy. With the emerging data of high local control efficacy with low toxicity of stereotactic ablative radiation (SAbR) for both CNS and extra-cranial mRCC, SAbR may play a critical role in the multi-modality management of mRCC patients with oligometastatic disease. In addition to local control benefit, the benefit of SAbR in this patient population can range from longitudinal disease control, maintaining quality of life, deferring systemic therapy, immune-modulation and even improving survival. A review of the retrospective data suggests that SAbR benefits oligometastatic mRCC patients with metachronous metastases, and perhaps those with indolent biology. Large prospective trials are indicated to successfully integrate SAbR of oligometastatic mRCC with the available systemic therapies to harness the optimal benefit of SAbR for this patient population.

Surgical Metastasectomy in the Spine: A Review Article

BACKGROUND

The use of surgical metastasectomy (SM) has increased across cancer types in recent decades despite the increasing efficacy of modern systemic treatment modalities. Symptomatic spinal metastases severely compromise patients' performance status. However, as spinal SM is a complex surgery with potentially significant complications, it is not considered the treatment of choice.

METHODS

We reviewed the articles on SM in several primary cancers with different types of metastatic lesions and extracted the data from relevant articles to provide a comprehensive review including the surgical techniques, indications, reported outcomes, and future prospects of SM in spinal metastases.

RESULTS

Total en bloc spondylectomy (TES) is a method of spinal SM associated with a lower risk of tumor recurrence and complications. Intralesional transpedicular osteotomy using a fine threadwire saw allows prevention of spinal cord and nerve root injuries. Spinal SM is considered suitable for patients with controlled primary disease having no evidence of disseminated extraspinal metastases, a completely resectable solitary lesion in the spine, and adequate cardiopulmonary reserve to tolerate the surgery. Metastatic lesions from kidney and thyroid cancers have been reported as the best candidates for spinal SM. Although data about spinal SM are limited, the reported outcomes are favorable with acceptable local recurrence rates in long-term follow-up.

CONCLUSION

In patients with isolated resectable spinal metastases, complete SM including TES is a useful option as it can improve function and survival. However, appropriate patient selection and surgical feasibility remain the most important aspects of management.

IMPLICATIONS FOR PRACTICE

Surgical metastasectomy for spinal metastases may be a potentially curative treatment option with a low risk of local recurrence and lead to prolonged long-term survival if appropriate patients are selected and if the surgery is carried out by experienced surgeons in high-volume centers.

Stereotactic Body Radiation Therapy With Simultaneous Integrated Boost in Patients With Spinal Metastases

Stereotactic body radiation therapy in patients with spine metastases maximizes local tumor control and preserves neurologic function. A novel approach could be the use of stereotactic body radiation therapy with simultaneous integrated boost delivering modality. The aim of the present study is to report our experience in the treatment of spine metastases using a frameless radiosurgery system delivering stereotactic body radiation therapy–simultaneous integrated boost technique. The primary endpoints were the pain control and the time to local progression; the secondary ones were the overall survival and toxicity. A total of 20 patients with spine metastases and 22 metastatic sites were treated in our center with stereotactic body radiation therapy–simultaneous integrated boost between December 2007 and July 2018. Stereotactic body radiation therapy–simultaneous integrated boost treatments were delivered doses of 8 to 10 Gy in 1 fraction to isodose line of 50%. The median follow-up was 35 months (range: 12-110). The median time to local progression for all patients was not reached and the actuarial 1-, 2-, and 3-years local free progression rate was 86.36%. In 17 of 20 patients, a complete pain remission was observed and 3 of 20 patients had a partial pain remission (complete pain remission + partial pain remission: 100%). The median overall survival was 38 months (range 12-83). None of the patients experienced neither radiation adverse events (grade 1-4) nor reported pain flair reaction. None of the patients included in our series experienced vertebral compression fracture. Spine radiosurgery with stereotactic body radiation therapy–simultaneous integrated boost is safe. The use of this modality in spine metastases patients provides an excellent local control.

Radiation Therapy for Patients with Advanced Renal Cell Carcinoma

Stereotactic radiosurgery and stereotactic body radiation therapy (SBRT) have led to a resurgence of the use of radiotherapy in the management of advanced renal cell carcinoma (RCC). These techniques provide excellent local control and palliation of metastatic sites of disease with minimal toxicity. Additionally, SBRT to the primary tumor may be efficacious and well tolerated in select patients that are not surgical candidates. Emerging data suggest that SBRT may potentiate the immune response, and current and future study will evaluate if SBRT can improve survival outcomes in patients with metastatic RCC.

Single fraction radiosurgery, fractionated radiosurgery, and conventional radiotherapy for spinal oligometastasis (SAFFRON): A systematic review and meta-analysis

BACKGROUND AND PURPOSE

To perform a systematic review/meta-analysis of outcomes for patients with spinal metastases treated with stereotactic radiosurgery (SRS) (either single-fraction (SF-SRS) or multiple-fraction (MF-SRS)) or conventional radiotherapy (RT).

MATERIALS AND METHODS

Thirty-seven studies were identified. Primary outcomes were 1-year local control (LC) and acute/late grade 3-5 toxicities (including vertebral compression fractures (VCF)). Weighted random effects meta-analyses using the DerSimonian and Laird methods and meta-regressions were conducted to characterize and compare effect sizes. Mixed effects regression models were used in dose analyses.

RESULTS

A total of 3237 patients with 4911 lesions were included; 43.8%, 19.7%, and 36.5% of lesions received SF-SRS, MF-SRS, or RT, respectively. SF-SRS resulted in improved 1-year LC (92.9% (95% CI: 86.4-97.4%); p = 0.007) compared to RT (81.0% (95% CI: 69.2-90.5%)) with no difference between MF-SRS (82.1%; p = 0.86) and RT. On subgroup analysis of de novo metastases, superior 1-year LC following SF-SRS (95.5% (95% CI: 87.4-99.6%)) was maintained compared to RT (83.6% (95% CI: 70.4-93.5%); p = 0.007). A 4.7% increase in LC was noted for each 10 Gy10 increase in biologically effective dose (BED10, assuming an alpha/beta = 10) with SRS (p < 0.001). No difference in toxicities were found between SF-SRS (0.4%), MF-SRS (0.2%), or RT (0%). Higher VCF rates were noted following SF-SRS (19.5%) vs. MF-SRS (9.6%; p = 0.039)) with no correlation between dose and VCF rates.

CONCLUSION

SF-SRS resulted in superior LC with a roughly 5% LC benefit for every 10 Gy10 increase in BED10 with higher VCF rates compared to MF-SRS. If LC is the goal of treatment, then SRS may be a preferred treatment modality. However, these results are hypothesis-generating, and prospective randomized clinical trials are indicated to definitively address the question of whether SRS results in improved LC compared to RT.

Outcomes of patients with spinal metastases from renal cell carcinoma treated with conventionally-fractionated external beam radiation therapy

Renal cell carcinoma (RCC) has been traditionally thought to be radioresistant. This retrospective cohort study aims to assess the outcomes of patients with spinal metastases from RCC treated with conventionally-fractionated external beam radiation therapy (cEBRT) in our institution.Patients diagnosed with histologically or radiologically-proven RCC who received palliative cEBRT to spinal metastases, using 3-dimensional conformal technique between 2009 and 2018 were reviewed. Local progression-free survival (PFS), overall survival (OS) and common terminology criteria for adverse events version 4.0-graded toxicity were assessed. Univariable and multivariable Cox proportional hazards regression analyses were performed to evaluate for predictors associated with survivals.Thirty-five eligible patients with forty spinal segments were identified, with a median follow-up of 7 months (range, 0-47). The median equivalent dose in 2 Gy fractions (EQD2) was 32.5 Gy 10 (range, 12-39). Thirty-seven percent of patients underwent surgical intervention. At the time of last follow-up, all but 1 patient had died. Seven patients developed local progression, with the median time to local progression of 10.2 months. The median local PFS and OS were 3.3 and 4.8 months. There was no grade 3 or higher toxicity. A higher radiation dose (equivalent dose to 2 Gy fraction <32.5 Gy 10 vs ≥32.5Gy 10) (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.17-3.18; P-value (P) = .68) and spinal surgery (HR, 2.35; 95% CI, 0.53-10.29; P = .26) were not significantly associated with local PFS on univariable analysis. Multivariable analysis showed that higher Tokuhashi score (HR, 0.41; 95% CI, 0.19-0.88; P = .02), lower number of spinal segments irradiated (HR, 1.18; 95% CI, 1.01-1.37; P = .04) and use of targeted therapy (HR, 0.41; 95% CI, 0.18-0.96; P = .04) were independent predictors for improved OS.For an unselected group of patients with RCC, there is no significant association between higher radiation dose and improved local control following cEBRT. This may be due to their short survivals. With the use of more effective systemic therapy, including targeted therapy and immunotherapy, survival will likely be prolonged. A tailored-approach is needed to identify patients with good prognosis who may still benefit from aggressive local treatments.

MRI-guided stereotactic ablative radiation therapy of spinal bone metastases: a preliminary experience

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.

Evaluation of spine structure stability at different locations during SBRT

BACKGROUND AND AIMS

Modern stereotactic body radiotherapy (SBRT) techniques and systems that use online image guidance offer frameless radiotherapy of spinal tumors and the ability to control intrafraction motion during treatment. These systems allow precise alignment of the patient during the entire treatment session and react immediately to random changes in this alignment. Online tracking data provide information about intrafractional changes, and this information can be useful for designing treatment strategies even if online tracking is not being used. The present study evaluated spine motion during SBRT treatment to assess the risk of verifying patient alignment only prior to starting treatment.

METHODS

This study included 123 patients treated with spine SBRT. We analyzed different locations within the spine using system log files generated during treatment, which contain information about differences in the pretreatment reference spine positions by CT versus positions during SBRT treatment. The mean spine motion and intra/interfraction motion was evaluated. We defined and assessed the spine stability and spine significant shifts (SSHs) during treatment.

RESULTS

We analyzed 462 fractions. For the cervical (C) spine, the greatest shifts were in the anterior-posterior (AP) direction (2.48 mm) and in pitch rotation (1.75 deg). The thoracic (Th) spine showed the biggest shift in the AP direction (3.68 mm) and in roll rotation (1.66 deg). For the lumbar-sacral (LS) spine, the biggest shift was found for left-right (LR) translation (3.81 mm) and roll rotation (3.67 deg). No C spine case exceeded 1 mm/1 deg for interfraction variability, but 7 of 54 Th spine cases exceeded 1 mm interfraction variability for translations (maximum value, 2.5 mm in the AP direction). The interfraction variability for translations exceeded 1 mm in 2 of 24 LS spine cases (maximum value, 1.7 mm in the LR direction). Only 13% of cases had no SSHs. The mean times to SSH were 6.5±3.9 min, 8.1±5.9 min, and 8.8±7.1 min for the C, Th, and LS spine, respectively, and the mean recorded SSH values were 1.6±0.66, 1.43±0.33, and 1.46±0.47 mm/deg, respectively.

CONCLUSION

Positional tracking during spine SBRT treatments revealed low mean translational and rotational shifts. Patient immobilization did not improve spine shifts compared with our results for the Th and LS spine without immobilization. For the most precise spine SBRT, we recommend checking the patient's position during treatment.

Outcomes of Posterior Thoracic Corpectomies for Metastatic Spine Tumors: An Analysis of 90 Patients

OBJECTIVE

To retrospectively analyze the outcomes and complications of patients with metastatic thoracic spinal tumors (MTTs) who underwent posterior corpectomies.

METHODS

Ninety patients with MTTs who underwent posterior corpectomies were retrospectively analyzed. Characteristics evaluated included number of MTTs per year, location, involved vertebrae numbers, sex, histology, pre- and postoperative American Spinal Injury Association (ASIA) grade, visual analog scale (VAS) pain scores, operative time, blood loss, and length of hospital stay.

RESULTS

The average follow-up was 20.8 ± 27.9 months (range, 0.5-139.4 months). Of the patients, 76.67% had a single metastasis and 23.33% had multiple metastases. For histology, 16.67% were breast, 15.56% were lung, 12.22% were prostate, and 12.22% were renal cell carcinoma. Of the patients with paraplegia and paraparesis, 74% improved. One patient improved from ASIA grade A to D, 3 patients improved from grade B to C, 8 patients improved from grade C to D or E, and 25 patients improved from grade D to E. Three patients (6%) with ASIA grade A and 1 patient (2%) with ASIA grade B had no improvement. One patient with ASIA grade C and 8 patients (16%) with grade D had no improvement. After surgery, VAS pain scores decreased from 8.45 ± 1.57 to 1.211 ± 1.81. In terms of complications, 2 patients (2.22%) had deep vein thrombosis and 1 patient had pulmonary embolism (1.11%). Other complications included wound infection (4.44%), cerebrospinal fluid leak (4.44%), pleural effusion (3.33%), wound dehiscence (2.22%), cellulitis (1.11%), epidural hematoma (1.11%), and pneumothorax (1.11%). Of the patients, 2.22% had implant failure and pseudoarthrosis, with 1 patient needing revision surgery. One patient (1.11%) had tumor recurrence.

CONCLUSIONS

Our results suggest that posterior thoracic corpectomies for MTTs have a reasonable complication rate with favorable outcomes.

Metastasis Affecting Craniocervical Junction: Current Concepts and an Update on Surgical Management

STUDY DESIGN

Literature review.

OBJECTIVES

Metastatic disease affecting the craniovertebral junction (CVJ) only accounts for 0.5% of all spine metastases. The management of these disease processes is complex, which involves multimodality radiological studies and various surgical approaches. We aimed to review the available evidence and summarize the findings in this review.

METHODS

The authors conducted search of PubMed and Google Scholar with the following search terms: metastasis, craniovertebral junction (CVJ), occipitocervical, approaches, stability, and radiotherapy. Articles were reviewed by the authors and determined for inclusion based on relevance and level of evidence.

RESULTS

The majority of relevant research reviewed composed of literature reviews of particular aspects regarding metastatic disease affecting the craniovertebral junction, including diagnosis, surgical approach, and radiotherapy.

CONCLUSIONS

Prompt evaluation of rotational neck pain with or without occipital neuralgia may reveal early metastatic disease within a stable CVJ. Magnetic resonance imaging appears to be the gold standard imaging modality in detecting this pathology, with nuclear bone scan playing a role in distinguishing benign and malignant processes. Unfortunately, no level 1 evidence exists for use of either radiotherapy or surgery in these cases; however, from the available literature, spinal instability and evidence of progressive neurology are relative indications for operative intervention.

[Technical aspects and indications of extracranial stereotactic radiotherapy]

Extracranial stereotactic radiotherapy has developed considerably in recent years and is now an important part of the therapeutic alternatives to be offered to patients with cancer. It offers opportunities that have progressively led physicians to reconsider the therapeutic strategy, for example in the case of local recurrence in irradiated territory or oligometastatic disease. The literature on the subject is rich but, yet, there is no real consensus on therapeutic indications. This is largely due to the lack of prospective, randomized studies that have evaluated this technique with sufficient recoil. We propose a review of the literature on the technical aspects and indications of extracranial stereotactic radiotherapy.

Surgical decompression for recurrent cord compression in cancer: a case series and review of the literature

Spine metastases affect a significant number of cancer patients each year, with the spine being the third most common location for cancer spread. As patients live longer with improved treatments, the opportunity for recurrence at previously treated sites increases. Here, we describe seven patients with recurrent, compressive, metastatic spine tumors at previously surgically treated sites that required additional surgical intervention with manipulation of at least one rod. Five of the patients had recurrence including adjacent levels while two had recurrence solely at the previously decompressed level. The patients remained ambulatory for an average of 31.2 months after the initial surgery. We also discuss the role of adjuvant treatment in these patients and review the literature.

State of the Art Treatment of Spinal Metastatic Disease

Treatment paradigms for patients with spine metastases have evolved significantly over the past decade. Incorporating stereotactic radiosurgery into these paradigms has been particularly transformative, offering precise delivery of tumoricidal radiation doses with sparing of adjacent tissues. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional radiation. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive, techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care, improving both local control and patient survivals. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists, and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases, integrating these data into a decision framework, NOMS, which integrates the 4 sentinel decision points in metastatic spine tumors: Neurologic, Oncologic, Mechanical stability, and Systemic disease and medical co-morbidities.

1x8 Gy versus 5x4 Gy for metastatic epidural spinal cord compression: a matched-pair study of three prognostic patient subgroups

BACKGROUND

This study provides separate comparisons of 1 × 8 Gy to 5 × 4 Gy for metastatic epidural spinal cord compression (MESCC) in patients with poor, intermediate and favorable survival prognoses.

METHODS

Patients receiving 1 × 8 Gy were matched to patients receiving 5 × 4 Gy for age, gender, performance status, tumor type, involved vertebrae, other bone metastases, visceral metastases, interval between tumor diagnosis and MESCC, ambulatory status and time developing motor deficits. From a study including patients with poor (N = 156) or intermediate (N = 86) survival prognoses, subgroup analyses were performed. Furthermore, 232 new patients with favorable prognoses matched the same way were included.

RESULTS

In poor prognoses patients, 6-month survival rates were 10% after 1 × 8 Gy and 6% after 5 × 4 Gy (p = 0.38); in-field reRT rates in few patients alive at 6 months were 15 and 2% (p = 0.16). In intermediate prognoses patients, 6-month survival rates were 49% after 1 × 8 Gy and 58% after 5 × 4 Gy (p = 0.30). ReRT rates at 6 months were 23 and 13% (p = 0.25). In favorable prognoses patients, 6-month survival rates were 89% after 1 × 8 Gy and 91% after 5 × 4 Gy. ReRT rates at 6 months were 14 and 3% (p = 0.007). In no subgroup, RT regimen had a significant impact on motor function.

CONCLUSIONS

Since in patients with poor prognoses, outcomes after 1 × 8 Gy and 5 × 4 Gy were not significantly different, 1 × 8 Gy may be an option. In patients with intermediate prognoses, a trend was found in favor of 5 × 4 Gy. In patients with favorable prognoses, need for in-field reRT was greater after 1 × 8 Gy.

Pain Relief by Cyberknife Radiosurgery for Spinal Metastasis

Aims and background

To report pain relief effect in patients with spinal metastases treated with Cyberknife® and to analyze the factors associated with pain relapse after initial pain relief.

Methods and study design.

We retrospectively analyzed patients with spinal metastasis treated with stereotactic body radiosurgery between April 2007 and June 2009. A total of 57 patients with 73 lesions were available for analysis with a median follow-up of 6.8 months (range, 1–30). Pain was assessed by a verbal/visual analogue scale at each visit: from 0 to 10. Pain relief was defined as a decrease of at least three levels of the pain score without an increase in analgesic use. Complete relief was defined as no analgesics or a score 0 or 1.

Results

Pain relief was achieved in 88% of the lesions, with complete relief in 51% within 7 days from the start of radiosurgery. The median duration of pain relief was 3.2 months (range, 1–30). Pain reappeared in 16 patients (27%). Spinal cord compression (P = 0.001) and performance status (P = 0.01) were predictive of pain relapse by multivariate Cox analysis. All 6 patients treated with solitary spinal metastasis experienced pain relief; 5 of them were alive without evidence of disease at a median of 16 months (range, 7–30).

Conclusions

As previous studies have shown, our study confirms that pain relief with spinal radiosurgery is around 90%. In particular, long-term pain relief and disease control was observed in patients with solitary spinal metastasis.

Intraoperative Radiotherapy during Kyphoplasty for Vertebral Metastases (Kypho-IORT): First Clinical Results

Aims and background

Kyphoplasty is an effective procedure providing structural stability and pain alleviation in vertebral metastases. To prevent early regrowth, patients typically receive postoperative fractionated radiotherapy, which is associated with long treatment duration. Therefore, we established a new approach to deliver intraoperative radiotherapy during kyphoplasty to shorten the treatment time and reach structural stability and sterilization of the metastases (Kypho-IORT).

Methods and study design

For Kypho-IORT, a 50 kV X-ray source with a specially designed applicator was used. A radiation dose of 8 Gy in 5 mm distance was delivered. After radiation the device was removed and the kyphoplasty was completed according to the standard procedure. Since August 2009, 18 patients with instable or painful spinal metastases received Kypho-IORT. The median age was 63 years (range, 43–73).

Results

Kypho-IORT was successfully performed in 18 of 21 vertebral lesions (86%). No severe complications occurred during or early after IORT. The median pain score using a visual analogue scale decreased from 5/10 before the procedure to 2.5/10 at day 1 (P <0.001) and to 0/10 six weeks after the procedure (P = 0.001). Imaging studies were available for 15 of 18 patients. Stable disease within the irradiated vertebral body was seen in 14 patients (93%) and local progressive disease in one patient (7%). No re-irradiation due to local progressive disease or pain recurrence was necessary within the median follow-up of 4.5 months.

Conclusions

Kypho-IORT is well tolerated without severe side effects and provides fast improvement of pain. Although stable disease was seen in 93% of the patients, a longer follow-up is necessary to assess the effectiveness. A dose escalation study to establish the maximally tolerated dose has been initiated.

Clinical outcomes of multileaf collimator-based CyberKnife for spine stereotactic body radiation therapy

OBJECTIVE

Stereotactic body radiotherapy (SBRT) for spinal metastases is becoming a prevalent therapeutic option. We aimed to evaluate the clinical feasibility and outcomes of the recently developed multileaf collimator (MLC)-based CyberKnife (CK-M) for spine SBRT.

METHODS

We reviewed 119 patients of 144 cases with 229 lesions treated with CK between November 2014 and March 2016. The lesion features, dosimetric parameters and clinical outcomes were compared between fixed cone collimator based CK (CK-F) and CK-M.

RESULTS

Of 144 cases, 78 and 66 were treated with CK-F and CK-M, respectively. CK-M achieved an adequate target volume coverage that was comparable with CK-F (median 92 vs 90%; p = 0.03) even in larger targets (median 64.2 vs 46.7 cm3; p = 0.01), respectively. CK-M showed an improvement in the gradient index (p < 0.001) and no difference in conformity (p = 0.16). With CK-M, the median beam delivery time was significantly reduced by 30% (to 34 vs 48 min; p < 0.001). CK-M showed 1 year local control rates that were comparable to CK-F (77 vs 78%, respectively; p = 0.83).

CONCLUSION

CK-M exhibits dosimetric data and local control that are comparable with CK-F, but with significant treatment time reduction. CK-M could be widely used in spine SBRT. Advances in knowledge: Given the recently developed MLC in CK, we aimed to evaluate the clinical feasibility and outcomes of MLC compared with fixed cone-based CK. MLC showed equivalent plan quality and significant treatment time reduction with comparable radiological control. We report here MLC as an effective and tolerable treatment option in CK.

Spinal Radiosurgery for Metastatic Disease of the Spine

Background

Metastatic tumor in the spinal column is common, causing symptomatic spinal cord compression in approximately 25,000 patients annually. Although surgical treatment of spinal metastases has become safer, less invasive, and more efficacious in recent years, there remains a subset of patients for whom other treatment modalities are needed. Stereotactic radiosurgery, which has long been used in the treatment of intracranial lesions, has recently been applied to the spine and enables the effective treatment of metastatic lesions.

Methods

We review the evolution of stereotactic radiosurgery and its applications in the spine, including a description of two commercially available systems.

Results

Although a relatively new technique, the use of stereotactic radiosurgery in the spine has advanced rapidly in the past decade. Spinal stereotactic radiosurgery is an effective and safe modality for the treatment of spinal metastatic disease.

Conclusions

Future challenges involve the refinement of noninvasive fiducial tracking systems and the discernment of optimal doses needed to treat various lesions. Additionally, dose-tolerance limits of normal structures need to be further developed. Increased experience will likely make stereotactic radiosurgery of the spine an important treatment modality for a variety of metastatic lesions.

Radiotherapy for renal cell carcinoma: renaissance of an overlooked approach

Conventional radiotherapy previously had a limited role in the definitive treatment of renal cell carcinoma (RCC), owing to the disappointing outcomes of several trials and the perceived radioresistance of this type of cancer. In this context, radiotherapy has been relegated largely to the palliation of symptoms in patients with metastatic disease, with variable rates of response. Following the availability of newer technologies that enable safe delivery of high-dose radiotherapy, stereotactic ablative radiotherapy (SABR) has become increasingly used in patients with RCC. Preclinical evidence demonstrates that RCC cells are sensitive to ablative doses of radiotherapy (≥8-10 Gy). Trials in the setting of intracranial and extracranial oligometastases, as well as primary RCC, have demonstrated excellent tumour control using this approach. Additionally, an awareness of the capacity of high-dose radiation to stimulate antitumour immunity has resulted in novel combinations of SABR with immunotherapies. Here we describe the historical application of conventional radiotherapy, the current biological understanding of the effects of radiation, and the clinical evidence supporting the use of ablative radiotherapy in RCC. We also explore emerging opportunities to combine systemic targeted agents or immunotherapies with radiation. Radiotherapy, although once an overlooked approach, is moving towards the forefront of RCC treatment.

Role of Radiotherapy in the Treatment of Renal Cell Cancer: Updated and Critical Review

Purpose

The growing incidence of renal cell carcinoma (RCC) raises many questions about the management of these patients. The late clinical presentation, the presence of locally advanced or metastatic disease at diagnosis, the difficulty of radical surgical excision, and radioresistance make it one of the more challenging tumors to treat. The primary objective of this article is to propose an updated and critical review of the role of radiotherapy (RT) in the treatment of RCC.

Methods

This literature review is based on data from meta-analyses and randomized, prospective, and retrospective studies. We collected reports from 1970 to the present about preoperative RT, postoperative RT, stereotactic body RT, radiosurgery, and intraoperative RT in locally advanced renal cancer and in metastatic diseases.

Results

We emphasize the progress made in RT technology that allowed the creation of a more personalized and focused treatment with a minimum rate of complications.

Conclusions

In the coming years, new studies will be published to confirm and increase the indications for use of RT.

Peripheral nervous system injury after high-dose single-fraction image-guided stereotactic radiosurgery for spine tumors

OBJECTIVE The object of this study was to determine the percentage of high-dose (1800-2600 cGy) single-fraction stereotactic radiosurgery (SF-SRS) treatments to the spine that result in peripheral nervous system (PNS) injury. METHODS All patients treated with SF-SRS for primary or metastatic spine tumors between January 2004 and May 2013 and referred to the Rehabilitation Medicine Service for evaluation and treatment of neuromuscular, musculoskeletal, or functional impairments or pain were retrospectively identified. RESULTS Five hundred fifty-seven SF-SRS treatments in 447 patients resulted in 14 PNS injuries in 13 patients. All injures resulted from SF-SRS delivered to the cervical or lumbosacral spine at 2400 cGy. The overall percentage of SF-SRS treatments resulting in PNS injury was 2.5%, increasing to 4.5% when the thoracic spine was excluded from analysis. The median time to symptom onset following SF-SRS was 10 months (range 4-32 months). The plexus (cervical, brachial, and/or lumbosacral) was affected clinically and/or electrophysiologically in 12 (86%) of 14 cases, the nerve root in 2 (14%) of 14, and both in 6 (43%) of 14 cases. All patients experienced pain and most (93%) developed weakness. Peripheral nervous system injuries were CTCAE Grade 1 in 14% of cases, 2 in 64%, and 3 in 21%. No dose relationship between SF-SRS dose and PNS injury was detected. CONCLUSIONS Single-fraction SRS to the spine can result in PNS injury with major implications for function and quality of life.

The impact of histology and delivered dose on local control of spinal metastases treated with stereotactic radiosurgery

OBJECTIVE An analysis of factors contributing to durable radiographic control of spinal metastases was undertaken, drawing from a large single-institution database in an attempt to elucidate indications and dose requirements for successful treatment. METHODS All patients treated at a single institution with stereotactic radiosurgery (SRS) of the spine as first-line therapy were assessed for local progression of the treated site, defined as radiographic enlargement of the treated tumor and/or biopsy-proven evidence of active tumor cells. All patients were followed with CT, PET, or MR imaging every 3-6 months until death. Treatment decisions were made by a multidisciplinary team of radiation oncologists, neurosurgeons, and neuroradiologists. Target volumes were defined according to the international consensus guidelines and were reviewed in a multidisciplinary conference. Image-guided techniques and intensity modulation were used for every case. The tumor's histological type, gross tumor volume (GTV), dose that covers 95% of the GTV (GTV D95), percentage of GTV covered by 95% of the prescribed dose (GTV V95), planning target volume (PTV), dose that covers 95% of the PTV (PTV D95), and percentage of PTV covered by 95% of the prescribed dose (PTV V95) were analyzed for significance in relation to local control, based on time to local progression. RESULTS A total of 811 lesions were treated in 657 patients between 2003 and 2015 at a single institution. The mean follow-up and overall survival for the entire cohort was 26.9 months (range 2-141 months). A total of 28 lesions progressed and the mean time to failure was 26 months (range 9.7-57 months). The median prescribed dose was 2400 cGy (range 1600-2600 cGy). Both GTV D95 and PTV D95 were highly significantly associated with local failure in univariate analysis, but GTV and PTV and histological type did not reach statistical significance. The median GTV D95 for the cohort equal to or above the GTV D95 1830 cGy cut point (high dose) was 2356 cGy, and it was 1709 cGy for the cohort of patients who received less than 1830 cGy (low dose). In terms of PTV D95, the median dose for those equal to or above the cut point of 1740 cGy (high dose) was 2233 cGy, versus 1644 cGy for those lesions below the PTV D95 cut point of 1740 cGy (low dose). CONCLUSIONS High-dose single-session SRS provides durable long-term control, regardless of the histological findings or tumor size. In this analysis, the only significant factors predictive of local control were related to the actual dose of radiation given. Although the target volumes were well treated with the intended dose, those lesions irradiated to higher doses (median GTV D95 2356 cGy, minimum 1830 cGy) had a significantly higher probability of durable local control than those treated with lower doses (median PTV D95 2232 cGy, minimum of 1740 cGy) (p < 0.001). Patients in the high-dose cohort had a 2% cumulative rate of local failure. Histological findings were not associated with local failure, suggesting that radioresistant histological types benefit in particular from radiosurgery. For patients with a favorable prognosis, a higher dose of SRS is important for long-term outcomes.

Percutaneous surgery for treatment of epidural spinal cord compression and spinal instability: technical note

OBJECTIVE An emerging paradigm for treating patients with epidural spinal cord compression (ESCC) caused by metastatic tumors is surgical decompression and stabilization, followed by stereotactic radiosurgery. In the setting of rapid progressive disease, interruption or delay in return to systemic treatment can lead to a negative impact in overall survival. To overcome this limitation, the authors introduce the use of spinal laser interstitial thermotherapy (sLITT) in association with percutaneous spinal stabilization to facilitate a rapid return to oncological treatment. METHODS The authors retrospectively reviewed a consecutive series of patients with ESCC and spinal instability who were considered to be poor surgical candidates and instead were treated with sLITT and percutaneous spinal stabilization. Demographic data, Spine Instability Neoplastic Scale score, degree of epidural compression before and after the procedure, length of hospital stay, and time to return to oncological treatment were analyzed. RESULTS Eight patients were treated with thermal ablation and percutaneous spinal stabilization. The primary tumors included melanoma (n = 3), lung (n = 3), thyroid (n = 1), and renal cell carcinoma (n = 1). The median Karnofsky Performance Scale score before and after the procedure was 60, and the median hospital stay was 5 days (range 3-18 days). The median Spine Instability Neoplastic Scale score was 13 (range 12-16). The mean modified postoperative ESCC score (2.75 ± 0.37) was significantly lower than the preoperative score (4.5 ± 0.27) (Mann-Whitney test, p = 0.0044). The median time to return to oncological treatment was 5 days (range 3-10 days). CONCLUSIONS The authors present the first cohort of sLITT associated with a percutaneous spinal stabilization for the treatment of ESCC and spinal instability. This minimally invasive technique can allow a faster recovery without prejudice of adjuvant systemic treatment, with adequate local control and spinal stabilization.

Spine radiosurgery: lessons learned from the first 100 treatment sessions

OBJECTIVE

Local therapy to spine tumors has been shown to be effective in selected cases. Spinal radiosurgery (SRS) is an evolving radiotherapy regimen allowing for noninvasive, highly efficacious local treatment. The learning curve can compromise the results of any newly employed technology and should be studied to minimize its effects. In this paper the first 100 SRSs performed at several medical centers are presented and analyzed for the effects of the learning curve on outcome.

METHODS

A retrospective analysis was undertaken to evaluate data from patients treated with SRS at Sheba Medical Center and Assuta Medical Centers in the period from September 2011 to February 2016. Medical history, clinical and neurological findings, pathological diagnoses, SRS variables, complications, and follow-up data were collected and analyzed. Local control rates were calculated, and local treatment failure cases were qualitatively studied.

RESULTS

One hundred treatment sessions were performed for 118 lesions at 179 spinal levels in 80 patients. The complication rate was low and did not correlate with a learning curve. Mean follow-up time was 302 days, and the overall local control rate was 95%. The local control rate was dose dependent and increased from 87% (among 35 patients receiving a dose of 16 Gy) to 97% (among 65 patients receiving a dose of 18 Gy). The 6 treatment failure cases are discussed in detail.

CONCLUSIONS

Spinal radiosurgery is a safe and effective treatment. Comprehensive education of the treating team and continuous communication are essential to limit the effects of the learning curve on outcome.

Spinal Laser Interstitial Thermal Therapy

BACKGROUND:

Although surgery followed by radiation effectively treats metastatic epidural compression, the ideal surgical approach should enable fast recovery and rapid institution of radiation and systemic therapy directed at the primary tumor.

OBJECTIVE:

To assess spinal laser interstitial thermotherapy (SLITT) as an alternative to surgery monitored in real time by thermal magnetic resonance (MR) images.

METHODS:

Patients referred for spinal metastasis without motor deficits underwent MR-guided SLITT, followed by stereotactic radiosurgery. Clinical and radiological data were gathered prospectively, according to routine practice.

RESULTS:

MR imaging-guided SLITT was performed on 19 patients with metastatic epidural compression. No procedures were discontinued because of technical difficulties, and no permanent neurological injuries occurred. The median follow-up duration was 28 weeks (range 10-64 weeks). Systemic therapy was not interrupted to perform the procedures. The mean preoperative visual analog scale scores of 4.72 (SD ± 0.67) decreased to 2.56 (SD ± 0.71, P = .043) at 1 month and remained improved from baseline at 3.25 (SD ± 0.75, P = .021) 3 months after the procedure. The preoperative mean EQ-5D index for quality of life was 0.67 (SD ± 0.07) and remained without significant change at 1 month 0.79 (SD ± 0.06, P = .317) and improved at 3 months 0.83 (SD ± 0.06, P = .04) after SLITT. Follow-up MR imaging after 2 months revealed significant decompression of the neural component in 16 patients. However, 3 patients showed progression at follow-up, 1 was treated with surgical decompression and stabilization and 2 were treated with repeated SLITT.

CONCLUSION:

MR-guided SLITT can be both a feasible and safe alternative to separation surgery in carefully selected cases of spinal metastatic tumor epidural compression.