Review of spinal radiosurgery: a minimally invasive approach for the treatment of spinal and paraspinal metastases

Efficacy of flattening filter-free beams with the acuros XB algorithm in thoracic spine stereotactic body radiation therapy

This study aimed to determine the dosimetric value of flattening filter-free (FFF) beams compared to flattening filter (FF) beams using different algorithms in the treatment planning of thoracic spine stereotactic body radiation therapy (SBRT). A total of 120 plans were created for 15 patients using the Anisotropic Analytical Algorithm (AAA) and the Acuros External Beam (AXB) algorithm with FF and FFF beams at 6 MV and 10 MV energies. Various dosimetric parameters were evaluated, including target coverage, dose spillage, and organs-at-risk sparing of the spinal cord and esophagus. Treatment delivery parameters, such as the monitor units (MUs), modulation factors (MFs), beam-on time (BOT), and dose calculation time (DCT), were also collected. Significant differences were observed in the dosimetric parameters when AXB was used for all energies (P < 0.05). 6 XFFF energy was the best option for target coverage, dose spillage, and organs-at-risk sparing. In contrast, dosimetric parameters had no significant difference when using the AAA. The AAA and AXB calculations showed that the 6 XFFF beam had the shortest DCT. The treatment delivery parameters indicated that 10 XFF beam required the fewest MUs and MFs. In addition, the 10 XFFF beam demonstrated the shortest BOT. For effective treatment of the thoracic spine using SBRT, it is recommended to use the 10 XFFF beam because of the short BOT. Moreover, the AXB algorithm should be used because of its accurate dose calculation in regions with tissue heterogeneity.

Vertebral Augmentation of Cancer-Related Spinal Compression Fractures: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

To compare the magnitude and duration of pain relief with vertebral augmentation to any other therapy for the treatment of cancer-related vertebral compression fractures through meta-analysis of randomized controlled trials.

SUMMARY OF BACKGROUND DATA

Derived from search on PubMed, EMBASE, CINAHL, Scopus, Central, Scopus, and Web of Science databases in May 2020. Studies selected were limited to randomized controlled trials comparing vertebral augmentation, either Balloon Kyphoplasty or Percutaneous Vertebroplasty (PVP) with or without additional therapy to any other intervention or placebo/sham.

METHODS

The methodological quality of each included study was assessed according to the Cochrane Collaboration's domain-based framework. Random effects model, Q test, and I2 statistics were implemented.

RESULTS

Of 180 records identified, 7 were considered relevant, and included 476 participants. The risk of bias was considered "Low" in all studies. In five of the studies, vertebral augmentation alone (either PVP or Balloon Kyphoplasty) comprised one group, while comparative treatments included nonsurgical management, Kiva implantation, PVP and radiofrequency therapy, PVP and chemotherapy, PVP and intrasomatic injection of steroid, and PVP with 125I seeds. Two studies compared PVP with an additional therapy against the standard of care. With regard to changes in pain severity, the effect sizes varied from 0.0 (95% -1.7 to 1.7) to -5.1 (95% -5.3 to -4.9). Most studies demonstrated a positive and statistically significant effect associated with PVP. Four of the seven studies demonstrated a clinically significant effect as well. Other than cement leakage, with an event rate of 0.24 (95% CI 0.11-0.44) or 24% (95% CI 11%-44%), there were no major adverse events consistently observed across multiple studies.

CONCLUSIONS

The included randomized controlled trials demonstrated an overall positive and statistically significant effect of vertebral augmentation surgeries, such as vertebroplasty and kyphoplasty, for the treatment of cancer-related vertebral compression fractures, especially when compared with nonsurgical management, radiofrequency ablation, or chemotherapy alone.Level of Evidence: 1.

Outcomes of metastatic spinal cord compression secondary to primary hepatocellular carcinoma with multidisciplinary treatments

Few studies have reported progression-free survival (PFS) and overall survival (OS) of Metastatic spinal cord compression (MSCC) patients with primary hepatocellular carcinoma (HCC) following surgery and adjuvant therapies. Enrolled in this study were 155 MSCC patients with primary HCC who received surgery and adjuvant therapies between 2000 and 2015. Kaplan-Meier methods and Cox’s proportional hazards regression mode were performed to investigate the clinical features and prognostic factors affecting PFS and OS. The median PFS and OS was 7.0 months and 9.7 months, respectively. 92.9% patients responded well to surgery according to the Visual Analogue Scale, Frankel Score and postoperative complication occurrences. 68 (43.9%) patients who received circumferential decompression achieved better PFS than the remaining 87 (56.1%) patients who received laminectomy. Favorable outcomes were achieved after surgery during the perioperative period. Circumferential decompression was associated with better PFS than laminectomy. The postoperative Frankel Score E, Eastern Cooperative Oncology Group performance score of 1 or 2, no visceral metastasis, administration of postoperative radiation and the use of Sorafenib were found to be significant predictors of better PFS and OS. Patients who previously underwent resection of primary HCC with/without liver transplantation tended to have a better OS.

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.

National Perspectives on the Training of Neurosurgery Residents in Stereotactic Radiosurgery

BACKGROUND

Despite the critical role played by neurosurgeons in performing radiosurgery, neurosurgery residents in Canada have limited exposure to radiosurgery during their training. A survey of neurosurgery residents and faculty along with radiation oncology faculty was conducted to analyze perspectives regarding incorporating formal radiosurgery training into the neurosurgery residency curriculum Methods: An online survey platform was employed. Descriptive statistics were used to summarize center and respondent characteristics. Categorical variables were compared using odds ratios and corresponding 95% confidence intervals. The chi-squared test was utilized to assess statistical significance. A value of p<0.05 was considered significant Results: The response rate was 31% (119/381); 87% (102/119) of respondents were from the neurosurgical specialty and 13% (17/119) from radiation oncology. Some 46% of residents (18/40) were "very uncomfortable" with radiosurgery techniques, and 57% of faculty (42/73) believed that dedicated radiosurgery training would be beneficial though impractical. No respondents felt that "no training" would be beneficial. A total of 46% of residents (19/41) felt that this training would be beneficial and that time should be taken away from other rotations, if needed, while 58% of faculty (42/73) and 75% (28/41) of residents believed that either 1 or 1-3 months of time dedicated to training in radiosurgery would suffice Conclusions: Canadian neurosurgeons are actively involved in radiosurgery. Despite residents anticipating a greater role for radiosurgery in their future, they are uncomfortable with the practice. With the indications for radiosurgery expanding, this training gap can have serious adverse consequences for patients. Considerations regarding the incorporation and optimal duration of dedicated radiosurgery training into the Canadian neurosurgery residency curriculum are necessary.

Management of metastatic spinal column neoplasms--an update

The increased survival of cancer patients due to the improvement and advancement of therapeutic modalities has promoted progressive increase in the prevalence of metastatic tumors of the spine, making it important for healthcare professionals to acquire knowledge in the field. Spinal column metastases are usually secondary to malignant neoplasm of the breast, lung and prostate, male gender being the most often affected and pain being the initial symptom in 90% of patients. It is estimated that 30-90% of terminally ill patients with cancer have metastases at some spinal column segment. Clinical history, physical and neurological assessments are critical to determine the degree and extent of the lesion, and therefore choose the appropriate imaging method to be requested. This study aims to perform a review and didactic description of the main aspects related to the physiopathology, diagnosis and treatment of this disease.

Comparison of external radiotherapy and percutaneous vertebroplasty for spinal metastasis

AIM

To compare the efficacy of external radiotherapy (ERT) and percutaneous vertebroplasty (PVP) for spinal metastasis.

METHODS

A total of 137 patients with 174 spinal metastases between June 2006 and April 2009 in our hospital were reviewed. For their spinal metastasis, 52 patients received ERT; 46 patients received PVP; and 39 patients received both ERT and PVP. Pain and neurological deficit response, overall survival, and side effects were evaluated.

RESULTS

ERT combined with PVP achieved pain remission in 84.8% of the patients, which was higher than ERT (72.5%) or PVP (76.3%) alone. It also showed a higher remission rate of neurological deficits (50%) than ERT (18.2%) or PVP (11.1%) alone. Toxicities from the employed treatments were mild. The Karnofsky Performance Score and visceral or brain metastases were the significant influencing factors for overall survival. Patients with spinal metastases derived from breast cancer had a significantly better overall survival than those whose spinal metastases were derived from lung cancer.

CONCLUSION

ERT combined with PVP can be a more effective treatment for spinal metastases; however, prospective randomized trials are needed to draw any definitive conclusion.

[Kyphoplasty in combination with intraoperative radiotherapy. Technical and regulatory characteristics of a concept for treatment of vertebral metastases]

BACKGROUND

Operative and radiotherapeutic procedures are available for the treatment of symptomatic vertebral metastases. The method for treatment of vertebral metastases presented in this article involves a combination of intraoperative radiotherapy (IORT) and kyphoplasty.

METHODS AND RESULTS

Kyphoplasty-IORT allows treatment of symptomatic vertebral metastases between vertebrae T3 and L5. With the patient under intubation narcosis an extrapedicular or bipedicular access to the vertebra is selected as for conventional kyphoplasty. This is followed by insertion of special sheaths of the radiation applicator and radiation therapy is intraoperatively administered via a radiation generator (Intrabeam®, Carl Zeiss Surgical, Oberkochen, Germany). The radiation dose is 8 Gy at a depth of 5-10 mm depending on the study protocol (50 kV X-radiation). Following radiation a conventional kyphoplasty procedure (Medtronic, USA) is carried out and the vertebra stabilized with cement.

CONCLUSIONS

The procedure presented demonstrates a new approach to treatment of vertebral metastases and represents a valuable alternative to previously established methods.

Survival and health-related quality of life in patients with spinal metastases originated from primary hepatocellular carcinoma

BACKGROUND

In recent years, there have been more and more clinical trails focused on patient-reported outcomes (PRO), especially in the assessment of quality of life (QOL). Previous report on QOL assessment on patients with spinal metastases from primary hepatocellular carcinoma (HCC) is rare. And there is no standard treatment for those patients.

OBJECTIVE

The purpose of the current study is to determine whether spinal surgery could improve QOL in HCC patients with spinal metastases and prolong their survival.

METHODS

We conducted a single-center, non-randomized, prospective, longitudinal study in two groups: surgery group and non-surgery group. When diagnosed, all eligible patients completed a baseline QOL assessment using the Functional Assessment of Cancer Therapy-Hepatobiliary (FACT-Hep) questionnaire. All patients' quality of life was subsequently assessed again at another 4 time points: 1, 3, 6 and 9 months after diagnosis.

RESULTS

From July 1, 2007 to March 31, 2009, we identified 62 patients (surgery group n = 29, non-surgery group n = 33) who were eligible for the observational study. Only 21 patients in the surgery group and 22 patients in the non-surgery group survived more than 9 months and completed all 5 follow-up QOL assessments. The median survival time was 12.6 months in the surgery group and 13.7 months in the non-surgery group (P = 0.530). The results suggested that whether in the surgery or non-surgery group, QOL scores in 9-month period after diagnosis decreased in the same mode, and surgical treatment for spinal metastases could improve neither patients' QOL nor survival.

CONCLUSION

Spinal surgery could not provide benefits for patients with spinal metastases from HCC in QOL or survival. We do not recommend surgical treatment for patients with metastases from HCC to the spine.

Helical tomotherapy for spine oligometastases from gastrointestinal malignancies

Purpose

This study evaluated the treatment effectiveness and proper radiation dose of helical tomotherapy (HT) in spine oligometastases from gastrointestinal cancers.

Materials and Methods

From 2006 to 2010, 20 gastrointestinal cancer patients were treated with HT for spine oligometastases (31 spine lesions). The gross tumor volume (GTV) was the tumor evident from magnetic resonance imaging images fused with simulation computed tomography images. Clinical target volume (CTV) encompassed involved vertebral bodies or dorsal elements. We assumed that the planning target volume was equal to the CTV. We assessed local control rate after HT for 31 spine metastases. Pain response was scored by using a numeric pain intensity scale (NPIS, from 0 to 10).

Results

Spine metastatic lesions were treated with median dose of 40 Gy (range, 24 to 51 Gy) and median 5 Gy per fraction (range, 2.5 to 8 Gy) to GTV with median 8 fractions (range, 3 to 20 fraction). Median biologically equivalent dose (BED, α/β = 10 Gy) was 52 Gy₁₀ (range, 37.5 to 76.8 Gy₁₀) to GTV. Six month local control rate for spine metastasis was 90.3%. Overall infield failure rate was 15% and outfield failure rate was 75%. Most patients showed pain relief after HT (93.8%). Median local recurrence free survival was 3 months. BED over 57 Gy₁₀ and oligometastases were identified as prognostic factors associated with improved local progression free survival (p = 0.012, p = 0.041).

Conclusion

HT was capable of delivering higher BED to metastatic lesions in close proximity of the spinal cord. Spine metastases from gastrointestinal tumors were sensitive to high dose radiation, and BED (α/β = 10 Gy) higher than 57 Gy₁₀ could improve local control.

Dosimetric and clinical review of helical tomotherapy

As a modality for delivering rotational therapy, helical tomotherapy offers dosimetric advantages by combining a continuously rotating gantry with a binary multileaf collimator. Helical tomotherapy, embodied in the TomoTherapy(®) Hi-Art II(®) system, delivers intensity-modulated fan beams in a helical pattern using binary multileaf collimator leaves while the couch is translated through the gantry. Helical tomotherapy offers the possibility of treating a variety of cases--from simple to complex--with improved target conformality and sensitive structure sparing compared with 3D or conventional static field IMRT plans, thereby allowing biologically effective dose escalation. For precise irradiation and possible treatment adaptation, the fully integrated on-board image-guidance system provides online volumetric images of patient anatomy using 3.5-MV x-ray beams and the xenon computed tomography detector. Several review articles were published before the year 2007 but emphasized the technical aspects of helical tomotherapy. In this article, we review very recent papers and focus on the dosimetric and clinical aspects of helical tomotherapy.

Survival rate and neurological outcome after operation for advanced spinal metastasis (Tomita's classification > or = type 4)

PURPOSE

We investigated whether primary malignancy entities and the extent of tumor resection have an effect on the survival rate and neurological improvement in patients with spinal metastases that extend beyond the vertebral compartment (Tomita's classification > or = type 4).

MATERIALS AND METHODS

We retrospectively reviewed 87 patients with advanced spinal metastasis who underwent surgery. They were divided into groups 1 and 2 according to whether they responded to adjuvant therapy or not, respectively. They were subdivided according to the extent of tumor resection: group 1, gross total resection (G1GT); group 1, subtotal resection (G1ST); group 2, gross total resection (G2GT); and group 2, subtotal resection (G2ST). The origin of the tumor, survival rate, extent of resection, and neurological improvement were analyzed.

RESULTS

Group 1 had a better survival rate than group 2. The G1GT subgroup showed a better prognosis than the G1ST subgroup. In group 2, the extent of tumor resection (G2GT vs. G2ST) did not affect survival rate. In all subgroups, neurological status improved one month after surgery, however, the G2ST subgroup had worsened at the last follow-up. There was no local recurrence at the last follow-up in the G1GT subgroup. Four out of 13 patients in the G2GT subgroup showed a local recurrence of spinal tumors and progressive worsening of neurological status.

CONCLUSION

In patients with spinal metastases (Tomita's classification > or = type 4), individuals who underwent gross total resection of tumors that responded to adjuvant therapy showed a higher survival rate than those who underwent subtotal resection. For tumors not responding to adjuvant therapy, we suggest palliative surgical decompression.