Spinal instability as defined by the spinal instability neoplastic score is associated with radiotherapy failure in metastatic spinal disease

Intraoperative radiotherapy combined with spinal stabilization surgery-a novel treatment strategy for spinal metastases based on a first single-center experiences

INTRODUCTION

Current treatment of spinal metastases (SM) aims on preserving spinal stability, neurological status, and functional status as well as achieving local control. It consists of spinal surgery followed by radiotherapy and/or systemic treatment. Adjuvant therapy usually starts with a delay of a few weeks to prevent wound healing issues. Intraoperative radiotherapy (IORT) has previously been successfully applied during brain tumor, breast and colorectal carcinoma surgery but not in SM, including unstable one, to date. In our case series, we describe the feasibility, morbidity and mortality of a novel treatment protocol for SM combining stabilization surgery with IORT.

METHODS

Single center case series on patients with SM. Single session stabilization by navigated open or percutaneous procedure using a carbon screw-rod system followed by concurrent 50 kV photon-IORT (ZEISS Intrabeam). The IORT probe is placed via a guide canula using navigation, positioning is controlled by IOCT or 3D-fluroscopy enabling RT isodose planning in the OR.

RESULTS

15 (8 female) patients (71 ± 10y) received this treatment between 07/22 and 09/23. Median Spinal Neoplastic Instability Score was 8 [7-10] IQR. Most metastasis were located in the thoracic (n = 11, 73.3%) and the rest in the lumbar (n = 4, 26.7%) spine. 9 (60%) patients received open, 5 (33%) percutaneous stabilization and 1 (7%) decompression only. Mean length of surgery was 157 ± 45 min. Eleven patients had 8 and 3 had 4 screws placed. In 2 patients radiotherapy was not completed due to bending of the guide canula with consecutive abortion of IORT. All other patients received 8 Gy isodoses at mdn. 1.5 cm [1.1-1.9, IQR] depth during 2-6 min. The patients had Epidural Spinal Cord Compression score 1a-3. Seven patients (46.7%) experienced adverse events including 2 surgical site infection (one 65 days after surgery).

CONCLUSION

50 kV photon IORT for SM and consecutive unstable spine needing surgical intervention is safe and feasible and can be a promising technique in selected cases.

Implant and construct decision-making in metastatic spine tumour surgery: a review of current concepts with a decision-making algorithm

STUDY DESIGN

Narrative Review.

OBJECTIVE

Metastatic spine tumour surgery (MSTS) is an important treatment modality of metastatic spinal disease (MSD). Increase in MSTS has been due to improvements in our oncological treatment, as patients have increased longevity and even those with poorer comorbidities are now being considered for surgery. However, there is currently no guideline on how MSTS surgeons should select the appropriate levels to instrument, and which type of implants should be utilised.

METHODS

The current literature on MSTS was reviewed to study implant and construct decision making factors, with a view to write this narrative review. All studies that were related to instrumentation in MSTS were included.

RESULTS

A total of 58 studies were included in this review. We discuss novel decision-making models that should be taken into account when planning for surgery in patients undergoing MSTS. These factors include the quality of bone for instrumentation, the extent of the construct required for MSTS patients, the use of cement augmentation and the choice of implant. Various studies have advocated for the use of these modalities and demonstrated better outcomes in MSTS patients when used appropriately.

CONCLUSION

We have established a new instrumentation algorithm that should be taken into consideration for patients undergoing MSTS. It serves as an important guide for surgeons treating MSTS, with the continuous evolvement of our treatment capacity in MSD.

LEVEL OF EVIDENCE IV

Does the Presence of Missing Data Affect the Performance of the SORG Machine-learning Algorithm for Patients With Spinal Metastasis? Development of an Internet Application Algorithm

BACKGROUND

The Skeletal Oncology Research Group machine-learning algorithm (SORG-MLA) was developed to predict the survival of patients with spinal metastasis. The algorithm was successfully tested in five international institutions using 1101 patients from different continents. The incorporation of 18 prognostic factors strengthens its predictive ability but limits its clinical utility because some prognostic factors might not be clinically available when a clinician wishes to make a prediction.

QUESTIONS/PURPOSES

We performed this study to (1) evaluate the SORG-MLA's performance with data and (2) develop an internet-based application to impute the missing data.

METHODS

A total of 2768 patients were included in this study. The data of 617 patients who were treated surgically were intentionally erased, and the data of the other 2151 patients who were treated with radiotherapy and medical treatment were used to impute the artificially missing data. Compared with those who were treated nonsurgically, patients undergoing surgery were younger (median 59 years [IQR 51 to 67 years] versus median 62 years [IQR 53 to 71 years]) and had a higher proportion of patients with at least three spinal metastatic levels (77% [474 of 617] versus 72% [1547 of 2151]), more neurologic deficit (normal American Spinal Injury Association [E] 68% [301 of 443] versus 79% [1227 of 1561]), higher BMI (23 kg/m 2 [IQR 20 to 25 kg/m 2 ] versus 22 kg/m 2 [IQR 20 to 25 kg/m 2 ]), higher platelet count (240 × 10 3 /µL [IQR 173 to 327 × 10 3 /µL] versus 227 × 10 3 /µL [IQR 165 to 302 × 10 3 /µL], higher lymphocyte count (15 × 10 3 /µL [IQR 9 to 21× 10 3 /µL] versus 14 × 10 3 /µL [IQR 8 to 21 × 10 3 /µL]), lower serum creatinine level (0.7 mg/dL [IQR 0.6 to 0.9 mg/dL] versus 0.8 mg/dL [IQR 0.6 to 1.0 mg/dL]), less previous systemic therapy (19% [115 of 617] versus 24% [526 of 2151]), fewer Charlson comorbidities other than cancer (28% [170 of 617] versus 36% [770 of 2151]), and longer median survival. The two patient groups did not differ in other regards. These findings aligned with our institutional philosophy of selecting patients for surgical intervention based on their level of favorable prognostic factors such as BMI or lymphocyte counts and lower levels of unfavorable prognostic factors such as white blood cell counts or serum creatinine level, as well as the degree of spinal instability and severity of neurologic deficits. This approach aims to identify patients with better survival outcomes and prioritize their surgical intervention accordingly. Seven factors (serum albumin and alkaline phosphatase levels, international normalized ratio, lymphocyte and neutrophil counts, and the presence of visceral or brain metastases) were considered possible missing items based on five previous validation studies and clinical experience. Artificially missing data were imputed using the missForest imputation technique, which was previously applied and successfully tested to fit the SORG-MLA in validation studies. Discrimination, calibration, overall performance, and decision curve analysis were applied to evaluate the SORG-MLA's performance. The discrimination ability was measured with an area under the receiver operating characteristic curve. It ranges from 0.5 to 1.0, with 0.5 indicating the worst discrimination and 1.0 indicating perfect discrimination. An area under the curve of 0.7 is considered clinically acceptable discrimination. Calibration refers to the agreement between the predicted outcomes and actual outcomes. An ideal calibration model will yield predicted survival rates that are congruent with the observed survival rates. The Brier score measures the squared difference between the actual outcome and predicted probability, which captures calibration and discrimination ability simultaneously. A Brier score of 0 indicates perfect prediction, whereas a Brier score of 1 indicates the poorest prediction. A decision curve analysis was performed for the 6-week, 90-day, and 1-year prediction models to evaluate their net benefit across different threshold probabilities. Using the results from our analysis, we developed an internet-based application that facilitates real-time data imputation for clinical decision-making at the point of care. This tool allows healthcare professionals to efficiently and effectively address missing data, ensuring that patient care remains optimal at all times.

RESULTS

Generally, the SORG-MLA demonstrated good discriminatory ability, with areas under the curve greater than 0.7 in most cases, and good overall performance, with up to 25% improvement in Brier scores in the presence of one to three missing items. The only exceptions were albumin level and lymphocyte count, because the SORG-MLA's performance was reduced when these two items were missing, indicating that the SORG-MLA might be unreliable without these values. The model tended to underestimate the patient survival rate. As the number of missing items increased, the model's discriminatory ability was progressively impaired, and a marked underestimation of patient survival rates was observed. Specifically, when three items were missing, the number of actual survivors was up to 1.3 times greater than the number of expected survivors, while only 10% discrepancy was observed when only one item was missing. When either two or three items were omitted, the decision curves exhibited substantial overlap, indicating a lack of consistent disparities in performance. This finding suggests that the SORG-MLA consistently generates accurate predictions, regardless of the two or three items that are omitted. We developed an internet application ( https://sorg-spine-mets-missing-data-imputation.azurewebsites.net/ ) that allows the use of SORG-MLA with up to three missing items.

CONCLUSION

The SORG-MLA generally performed well in the presence of one to three missing items, except for serum albumin level and lymphocyte count (which are essential for adequate predictions, even using our modified version of the SORG-MLA). We recommend that future studies should develop prediction models that allow for their use when there are missing data, or provide a means to impute those missing data, because some data are not available at the time a clinical decision must be made.

CLINICAL RELEVANCE

The results suggested the algorithm could be helpful when a radiologic evaluation owing to a lengthy waiting period cannot be performed in time, especially in situations when an early operation could be beneficial. It could help orthopaedic surgeons to decide whether to intervene palliatively or extensively, even when the surgical indication is clear.

Risk Factors for Radiotherapy Failure in the Treatment of Spinal Metastases

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To build a predictive model for risk factors for failure of radiation therapy, hypothesizing a higher SINS would correlate with failure.

METHODS

Patients with spinal metastasis being treated with radiation at a tertiary care academic center between September 2014 and October 2018 were identified. The primary outcome measure was radiation therapy failure as defined by persistent pain, need for re-irradiation, or surgical intervention. Risk factors were primary tumor type, Karnofsky and ECOG scores, time to treatment, biologically effective dose (BED) calculations using α/β ratio = 10, and radiation modality. A logistic regression was used to construct a prediction model for radiation therapy failure.

RESULTS

One hundred and seventy patients were included. Median follow up was 91.5 days. Forty-three patients failed radiation therapy. Of those patients, 10 required repeat radiation and 7 underwent surgery. Thirty-six patients reported no pain relief, including some that required re-irradiation and surgery. Total SINS score for those who failed reduction therapy was <7 for 27 patients (62.8%), between 7-12 for 14 patients (32.6%), and >12 for 2 patients (4.6%). In the final prediction model, BED (OR .451 for BED > 43 compared to BED ≤ 43; P = .174), Karnofksy score (OR .736 for every 10 unit increase in Karnofksy score; P = .008), and gender (OR 2.147 for male compared to female; P = .053) are associated with risk of radiation failure (AUC .695). A statistically significant association between SINS score and radiation therapy failure was not found.

CONCLUSIONS

In the multivariable model, BED ≤ 43, lower Karnofksy score, and male gender are predictive for radiotherapy failure. SINS score was among the candidate risk factors included in multivariable model building procedure, but it was not selected in the final model.

LEVEL OF EVIDENCE

Prognostic level III.

Denosumab administration for bone metastases from solid tumors: a retrospective cross-sectional study

BACKGROUND

Little is known on how denosumab reduces skeletal-related events (SREs) by bone metastases from solid tumors. We sought to evaluate the effect of denosumab administration in patients with bone metastases from solid tumors.

METHODS

Data of patients treated with denosumab were collected from electronic medical charts (n = 496). Eligible participants in this study were adult patients (age ≥ 18 years) with metastatic bone lesions from solid tumors treated with denosumab. SREs, surgical interventions, the spinal instability neoplastic score (SINS) for spinal region, and Mirels' score for the appendicular region were evaluated. To assess whether denosumab could prevent SREs and associated surgery, the SINS and Mirels' score were compared between patients with and without SREs.

RESULTS

A total of 247 patients (median age, 65.5 years old; median follow-up period, 13 months) treated with denosumab for metastatic bone lesions from solid tumors were enrolled in this study. SREs occurred in 19 patients (7.7%). SREs occurred in 2 patients (0.8%) who took denosumab administration before SREs. Surgical interventions were undertaken in 14 patients (5.7%) (spinal and intradural lesions in five patients and appendicular lesions in nine patients). The mean SINS of patients without SREs compared to those with SREs were 7.5 points and 10.2 points, respectively. The mean Mirels' scores of non-SREs patients and those with SREs were 8.07 points and 10.7 points, respectively. Patients with SREs had significantly higher Mirels' score than non-SREs patients (p < 0.01). Patients with SREs had higher SINS than non-SREs patients (p = 0.09).

CONCLUSIONS

SREs occurred in patients with higher SINS or Mirels' scores. Two patients suffered from SREs though they took denosumab administration before SREs. Appropriate management of denosumab for patients with bone metastasis is significant. Surgical interventions may be needed for patients who with higher SINS or Mirel's scores.

Spine Instability Neoplastic Score (SINS) as a Predictive Tool in Conventional Radiotherapy: A Narrative Review

AIMS

This narrative review seeks to identify the SINS score application in the radiation oncology field.

METHODS

This literature review was performed searching papers on MEDLINE published from January 2010 to August 2022.

RESULTS

In terms of vertebral painful lesions and RT symptomatic responses, the SINS score could be an interesting aid in order to choose the right therapeutic approach. Lesions with higher level of instability, and therefore higher SINS score, could did not find any significant benefit from radiation therapy which is more effective on the tumor-related pain component. For SINS as a predictor of adverse event after RT or its changes after RT, we obtained contrasting results.

CONCLUSIONS

The reported few experiences showed ambiguous conclusions. Further prospective studies are needed.

Palliative radiotherapy of bone metastases in octogenarians: How do the oldest olds respond? Results from a tertiary cancer center with 288 treated patients

BACKGROUND

Accompanied by the demographic change, the number of octogenarian cancer patients with bone metastases will increase in the future. Palliative radiotherapy constitutes an effective analgesic treatment; however, as pain perception and bone metabolism change with increasing age, the analgesic efficacy of radiotherapy may be altered in elderly patients. We therefore investigated the treatment outcomes of palliative radiotherapy for bone metastases in octogenarians.

METHODS

Patients between 80 and 89 years undergoing radiotherapy for bone metastases between 2009 and 2019 at a tertiary cancer center were analyzed for patterns-of-care, pain response and overall survival (OS). Logistic regression analyses were carried out to examine parameters associated with pain response, and Cox analyses were conducted to reveal prognostic parameters for OS.

RESULTS

A total of 288 patients with 516 irradiated lesions were included in the analysis. The majority (n = 249, 86%) completed all courses of radiotherapy. Radiotherapy led to pain reduction in 176 patients (61%) at the end of treatment. Complete pain relief at the first follow-up was achieved in 84 patients (29%). Bisphosphonate administration was significantly associated with higher rates of pain response at the first follow-up (p < 0.05). Median OS amounted to 9 months, and 1-year, 2-year and 3-year OS were 43%, 28% and 17%. In the multivariate analysis, ECOG (p < 0.001), Mizumoto score (p < 0.01) and Spinal Instability Neoplastic Score (SINS) (p < 0.001) were independent prognosticators for OS.

CONCLUSION

Palliative radiotherapy for bone metastases constitutes a feasible and effective analgesic treatment in octogenarian patients. ECOG, Mizumoto score and SINS are prognosic variables for survival and may aid treatment decisions regarding radiotherapy fractionation in this patient group. Single-fraction radiotherapy with 8 Gy should be applied for patients with uncomplicated bone metastases and poor prognosis. Prospective trials focusing on quality of life of these very old cancer patients with bone metastases are warranted to reveal the optimal radiotherapeutic management for this vulnerable population.

Evaluation of prognostic preoperative factors in patients undergoing surgery for spinal metastases: Results in a consecutive series of 81 cases

Background:

Surgical treatment of spinal metastases should be tailored to provide pain control, neurological deficit improvement, and vertebral stability with low operative morbidity and mortality. The aim of this study was to analyze the predictive value of some preoperative factors on overall survival in patients undergoing surgery for spinal metastases.

Methods:

We retrospectively analyzed a consecutive series of 81 patients who underwent surgery for spinal metastases from 2015 and 2021 in the Clinic of Neurosurgery of Ancona (Italy). Data regarding patients’ baseline characteristics, preoperative Karnofsky Performance Status Score (KPS), and Frankel classification grading system, histology of primary tumor, Tokuhashi revised and Tomita scores, Spine Instability Neoplastic Score, and Epidural Spinal Cord Compression Classification were collected. We also evaluated the interval time between the diagnosis of the primary tumor and the onset of spinal metastasis, the type of surgery, the administration of adjuvant therapy, postoperative pain and Frankel grade, and complications after surgery. The relationship between patients’ overall survival and predictive preoperative factors was analyzed by the Kaplan–Meier method. For the univariate and multivariate analysis, the log-rank test and Cox regression model were used. P ≤ 0.05 was considered as statistically significant.

Results:

After surgery, the median survival time was 13 months. In our series, the histology of the primary tumor (P < 0.001), the Tomita (P < 0.001) and the Tokuhashi revised scores (P < 0.001), the preoperative KPS (P < 0.001), the adjuvant therapy (P < 0.001), the postoperative Frankel grade (P < 0.001), and the postoperative pain improvement (P < 0.001) were significantly related to overall survival in the univariate analysis. In the multivariate analysis, the Tomita (P < 0.001), Tokuhashi revised scores (P < 0.001), and the adjuvant therapy were confirmed as independent prognostic factors.

Conclusion:

These data suggest that patients with limited extension of primitive tumor and responsive to the adjuvant therapy are the best candidates for surgery with better outcome.

Simplified Chinese Version of the Spinal Instability Neoplastic Score in Evaluating Patients with Metastatic Spinal Tumor: A Cross-Cultural Adaptation and Validation

Objective

To translate the original English version of the Spinal Instability Neoplastic Score (SINS) into simplified Chinese, adapt it cross‐culturally, validate its psychometric properties in measuring spinal instability in patients with metastatic spinal tumors in the Chinese mainland, examine the reliability and validity to demonstrate its accuracy and applicability in clinical practice.

Methods

Patients diagnosed with metastatic spinal disease between January 2016 and January 2020 were recruited. The number of participants was advised to be at least 50 for appropriate analysis of reliability, construct validity, as well as ceiling or floor effects, and recruitment of 100 patients was advised for internal consistency analysis. The study was conducted in two phases: first, the SINS was translated into simplified Chinese; second, the factor structure, internal consistency, test–retest reliability, validity, and floor and ceiling effects of the SC‐SINS were assessed. The internationally recognized cross‐cultural adaptation guidelines were followed. Internal consistency was evaluated with Cronbach's alpha. Test–retest reliability was examined among the patients with a 4‐week interval. The validity of the Chinese version of SINS (SC‐SINS) was assessed by examining its relationship with Kostuik classification. Principal component analysis was conducted to confirm the factor structure of each subscale.

Results

A total of 160 participants (88 males and 72 females) were enrolled. No major difficulties occurred in the forward and backward translations of SINS. The internal consistency of SC‐SINS was excellent (Cronbach's α =0.857, ranging from 0.68 to 0.85). Test–retest reliability was also excellent with a value of 0.89, ranging from 0.86 to 0.95. Validity analyses indicated that the SC‐SINS was positively and significantly correlated with Kostuik classification. The correlation between “Posterolateral Involvement of Spinal Elements” and “1‐2 Partial Damage” was the highest with a correlation value of 0.792. The correlation between “Pain” and “1–2 Partial Damage” was the lowest with a value of 0.341. All items showed principal component coefficients greater than 0.4. The values of Factor 1 ranged from 0.523 to 0.681; Factor 2 ranged from 0.591 to 0.731; Factor 3 ranged from 0.613 to 0.754; Factor 4 ranged from 0.461 to 0.711; Factor 5 ranged from 0.513 to 0.701; and Factor 6 ranged from 0.501 to 0.668. In addition, neither floor nor ceiling effects were seen in the SC‐SINS.

Conclusion

The SC‐SINS demonstrated high internal consistency and test–retest reliability, which has been proven valid and reliable to measure spinal stability in patients from the Chinese mainland with metastatic spinal tumor.

Treatment Outcomes in Spinal Metastatic Disease With Indeterminate Stability

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to compare outcomes between different treatment modalities for metastatic disease with indeterminate instability (Spinal Instability Neoplastic Score [SINS] 7-12).

METHODS

We retrospectively reviewed neurologically intact patients treated for spinal metastatic disease with a SINS of 7 to 12. The cohort was stratified by treatment approach: external beam radiation therapy alone (EBRT), surgery + EBRT (S+E), and cement augmentation + EBRT (K+E). Kaplan-Meier analysis was used to assess differences in length of survival (LOS) and ability to ambulate at time of death. Multivariate analysis was performed to assess adjusted LOS and ability to ambulate at time of death.

RESULTS

The cohort included 211 patients, S+E (n = 57), EBRT (n = 128), and K+E (n = 27). In the S+E group, the median LOS was 430 days, which was statistically longer than the median LOS for the EBRT group (121 days) and the K+E group (169 days). In the S+E group, 52 patients (91.2%) and in the K+E group 24 patients (92.3%) retained the ability to ambulate at their time of death compared to 99 patients (77.3%) of the EBRT patients (P = .01). The overall rate of revision treatment at the spinal level initially treated was 17.5%, S+E (15.8%), EBRT (20.3%), and K+E (7.7%).

CONCLUSIONS

The length of survival, ability to maintain ambulatory ability, and revision treatment rates were all improved following surgical management and radiation therapy compared to radiation therapy alone. The authors' conclusion from these results are that patients with indeterminate spinal instability should be discussed in a multidisciplinary setting for the need of spinal stabilization in addition to radiation therapy.

Ten Years After SINS: Role of Surgery and Radiotherapy in the Management of Patients With Vertebral Metastases

The objective of the different types of treatments for a spinal metastasis is to provide the best oncological and functional result with the least aggressive side effects. Initially created in 2010 to help clinicians in the management of vertebral metastases, the Spine Instability Neoplastic Score (SINS) has quickly found its place in the decision making and the treatment of patients with metastatic spinal disease. Here we conduct a review of the literature describing the different changes that occurred with the SINS score in the last ten years. After a brief presentation of the spinal metastases’ distribution, with or without spinal cord compression, we present the utility of SINS in the radiological diagnosis and extension of the disease, in addition to its limits, especially for scores ranging between 7 and 12. We take this opportunity to expose the latest advances in surgery and radiotherapy concerning spinal metastases, as well as in palliative care and pain control. We also discuss the reliability of SINS amongst radiologists, radiation oncologists, spine surgeons and spine surgery trainees. Finally, we will present the new SINS-derived predictive scores, biomarkers and artificial intelligence algorithms that allow a multidisciplinary approach for the management of spinal metastases.

eCross-cultural adaptation of the spine oncology-specific SOSGOQ2.0 questionnaire to German language and the assessment of its validity and reliability in the clinical setting

Background

The recently developed Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0) was proven a valid and reliable instrument measuring health-related quality of life (HRQOL) for patients with spinal malignancies. A German version was not available.

Objective

A cross-cultural adaptation of the SOSGOQ2.0 to the German language and its multicenter evaluation.

Methods

In a multistep process, a cross-cultural adaptation of the SOSGOQ2.0 was conducted. Subsequently, a multicenter, prospective observational cohort study was initiated to assess the reliability and validity of the German adaptation. To assess external construct validity of the cross-cultural adapted questionnaire, a comparison to the established questionnaire QLQ-C30 from the European Organisation for Research and Treatment of Cancer was conducted. Mean-difference plots were used to measure the agreement between the questionnaires in total score and by domain (deviation from mean up to 10% allowed). Further reliability and validity tests were carried out. Change to baseline was analysed 3–16 weeks later after different interventions occurred. Clinically relevant thresholds in comparison to the EORTC QLQ-C30 questionnaire were evaluated by ROC curve analysis.

Results

We could enroll 113 patients from four different university hospitals (58 females, 55 males). Mean age was 64.11 years (sd 11.9). 80 patients had an ECOG performance status of 2 or higher at baseline. External construct validity in comparison to the EORTC QLQ-C30 questionnaire in total score and by domain was confirmed (range of deviation 4.4 to 9.0%). Good responsiveness for the domains Physical Functioning (P < .001) and Pain (P < .001) could be shown. The group mean values also displayed a difference in the domains of Social Functioning (P = .331) and Mental Health (P = .130), but not significant. The minimum clinically relevant threshold values for the questionnaire ranged from 4.0 to 7.5 points.

Conclusions

According to our results, the cross-cultural adapted questionnaire is a reliable and valid tool to measure HRQOL in German speaking patients with spinal malignancies. Especially the domains Physical Functioning and Pain showed overall good psychometric characteristics. In this way, a generic questionnaire, such as the EORTC QLQ-C30, can be usefully supplemented by spine-specific questions to increase the overall accuracy measuring HRQOL in patients with spinal malignancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08578-x.

Current Management of Bone Metastases from Differentiated Thyroid Cancer

Simple Summary

Patients with bone metastases (BMs) from differentiated thyroid carcinoma (DTC) can live longer than those with BMs from other cancers. BMs from DTC create destructive lesions and easily cause intractable pain and neurological symptoms, including paralysis. These symptoms related to BMs affect mortality directly and indirectly by hampering the application of systemic therapies. Therefore, long-term local control of BMs in patients with DTC is desired, especially in patients with single or a small number of metastases. Local treatments for BMs have recently become advanced and sophisticated in surgery, radiotherapy, and percutaneous procedures. These therapies, either alone or in combination with other treatments, can effectively improve, or prevent the deterioration of, the performance status and quality of life of patients with DTC-BM. Among local therapies, complete surgical resection and stereotactic radiosurgery are the mainstay for achieving long-term control of DTC-BM.

Abstract

After the lung, the skeleton is the second most common site of distant metastases in differentiated thyroid carcinoma (DTC). Patients with osteolytic bone metastases (BMs) from thyroid carcinoma often have significantly reduced performance status and quality of life. Recent advancements in cancer therapy have improved overall survival in multiple cancer subtypes, including thyroid cancer. Therefore, long-term local control of thyroid BMs is desired, especially in patients with a single metastasis or oligometastases. Here, we reviewed the current management options for DTC-BMs and especially focused on local treatments for long-term local tumor control from an orthopedic tumor surgeon’s point of view. Metastasectomy and stereotactic radiosurgery can be performed either alone or in combination with radioiodine therapy and kinase inhibitors to cure skeletal lesions in selected patients. Percutaneous procedures have been developed in recent years, and they can also have a curative role in small BMs. Recent advancements in local therapies have the potential to provide not only long-term local tumor control but also a better prognosis.

Predictive Value of the Spinal Instability Neoplastic Score for Survival and Ambulatory Function After Surgery for Metastatic Spinal Cord Compression in 110 Patients with Prostate Cancer

STUDY DESIGN

We retrospectively analyzed Spinal Instability Neoplastic Score (SINS) in 110 patients with prostate cancer operated for metastatic spinal cord compression (MSCC).

OBJECTIVE

We aimed to investigate the association between SINS and clinical outcomes after surgery for MSCC in patients with prostate cancer.

SUMMARY OF BACKGROUND DATA

The SINS is a useful tool for assessing tumor-related spinal instability, but its prognostic value regarding survival and neurological outcome is still controversial.

METHODS

We analyzed 110 consecutive patients with prostate cancer who underwent surgery for MSCC. The patients were categorized according to their SINS. Patients with castration-resistant prostate cancer (CRPC, n = 84) and those with hormone-naïve disease (n = 26) were analyzed separately.

RESULTS

In total, 106 of 110 patients met the SINS criteria for potential instability or instability (scores 7-18). The median SINS was 10 (range 6-15) for patients with CRPC and 9 (7-16) for hormone-naïve patients. In the CRPC group, the SINS was classified as stable (score 0-6) in 4 patients, as potentially unstable (score 7-12) in 70 patients, and as unstable (score 13-18) in 10 patients. In the hormone-naïve group, 22 patients met the SINS criteria for potential instability and 4 patients for instability. There was no statistically significant difference in the overall risk for death between the SINS potentially unstable and unstable categories (adjusted hazard ratio 1.3, P = 0.4), or in the risk of loss of ambulation 1 month after surgery (adjusted odds ratio 1.4, P = 0.6).

CONCLUSION

The SINS is helpful in assessing spinal instability when selecting patients for surgery, but it does not predict survival or neurological outcomes. Patients with a potential spinal instability benefit equally from surgery for MSCC as do patients with spinal instability.Level of Evidence: 3.

An Overview of Decision Making in the Management of Metastatic Spinal Tumors

INTRODUCTION

Spinal metastases are the most commonly encountered spinal tumors. With increasing life expectancy and better systemic treatment options, the incidence of patients seeking treatment for spinal metastasis is rising. Radical resections and conventional low-dose radiotherapy have given way to modern 'separation' surgeries and stereotactic body radiotherapy which entails lesser morbidity and improved local control. This article provides an overview of the decision making and currently available treatment options for metastatic spinal tumors.

METHODS

A MEDLINE literature search was made for studies in English language reporting on human subjects, describing results of various treatment options that are a part of multidisciplinary management of metastatic spinal tumors. The highest-quality evidence available in the literature was reviewed.

DISCUSSION

Treatment of patients with metastatic spinal tumors is largely palliative, with radiotherapy and selective surgery being the mainstays of management. Multidisciplinary management that incorporates factors like patient performance status, expected survival and systemic burden of disease and employs well-validated decision-making frameworks for guiding treatment holds the key to an effective palliative treatment strategy. Effective pain management, achieving local control, adequate neurological decompression in the setting of epidural cord compression and surgical stabilization for mechanical stabilization are the main goals of treatment.

CONCLUSION

The management of metastatic spinal tumors has been rapidly evolving; currently, limited decompression and stabilization followed by postoperative SBRT for local tumor control are associated with less morbidity and may be referred to as the current standard of care in these patients.

Health related quality of life outcomes following surgery and/or radiation for patients with potentially unstable spinal metastases

BACKGROUND

Currently there is no prospective pain and health related quality of life (HRQOL) data of patients with potentially unstable spinal metastases who were treated with surgery ± radiation or radiation alone.

METHODS

An international prospective cohort multicenter study of patients with potentially unstable spinal metastases, defined by a SINS score 7 to 12, treated with surgery ± radiation or radiotherapy alone was conducted. HRQOL was evaluated with the numeric rating scale (NRS) pain score, the SOSGOQ2.0, the SF-36, and the EQ-5D at baseline and 6, 12, 26, and 52 weeks after treatment.

RESULTS

A total of 136 patients were treated with surgery ± radiotherapy and 84 with radiotherapy alone. At baseline, surgically treated patients were more likely to have mechanical pain, a lytic lesion, a greater median Spinal Instability Neoplastic score, vertebral compression fracture, lower performance status, HRQOL, and pain scores. From baseline to 12 weeks post-treatment, surgically treated patients experienced a 3.0-point decrease in NRS pain score (95% CI -4.1 to -1.9, p<.001), and a 12.7-point increase in SOSGOQ2.0 score (95% CI 6.3-19.1, p<.001). Patients treated with radiotherapy alone experienced a 1.4-point decrease in the NRS pain score (95% CI -2.9 to 0.0, p=.046) and a 6.2-point increase in SOSGOQ2.0 score (95% CI -2.0 to 14.5, p=.331). Beyond 12 weeks, significant improvements in pain and HRQOL metrics were maintained up to 52-weeks follow-up in the surgical cohort, as compared with no significant changes in the radiotherapy alone cohort.

CONCLUSIONS

Patients treated with surgery demonstrated clinically and statistically significant improvements in pain and HRQOL up to 1-year postsurgery. Treatment with radiotherapy alone resulted in improved pain scores, but these were not sustained beyond 3 months and HRQOL outcomes demonstrated nonsignificant changes over time. Within the SINS potentially unstable group, distinct clinical profiles were observed in patients treated with surgery or radiotherapy alone.

Pre-radiotherapy pain intensity and health-related quality of life in patients with bone metastases at various vertebral levels

PURPOSE

The spine is the most common site of bone metastasis from cancer and can be divided into 5 locational subsections, varying in mobility. The purpose of this research was to determine if the mobility of the metastases-bearing vertebral segment influenced pre-treatment pain intensity or health-related quality of life (HR-QoL) for patients about to receive palliative radiation therapy for painful spine metastasis.

METHODS

This study was a retrospective chart review of patients referred to the Palliative Radiation Oncology Program, about to receive radiation therapy for vertebral metastasis between January 2014 and June 2016. The main variables included patient-reported Edmonton Symptom Assessment Score pain intensity, the EQ-5D score for HR-QoL and the location of the vertebral metastasis (categorized using the SINS mobility score (mobile, junctional, semi-rigid, or rigid)). Various patient, disease and treatment characteristics were also collected, and entered into a multivariate analysis.

RESULTS

The eligible sample included 196 patients. Spinal metastases were distributed with approximately equal frequency (~27%) between the junctional, mobile and semi-rigid spine segments. Rigid spine was the least common site for spinal metastases (19%). Patients with metastatic disease in the mobile spine regions experienced greater pre-treatment pain compared to patients with disease in junctional subsections (Odds Ratio [OR] 1.37; p0.012). No relationship between HR-QOL and spinal mobility was found. Multivariate analysis also revealed that spinal metastases from a primary lung diagnosis reported worse pre-treatment pain compared to those from genitourinary cancers (OR 1.15; p0.05). Only age significantly influenced HR-QoL (75-95yrs vs. 35-55yrs; p0.041).

CONCLUSIONS

Patients referred to an RT clinic for the treatment of painful spinal metastases have a different distribution of disease throughout the spine compared to those referred for surgery or SBRT. Those with metastases in mobile spine segments were more likely to experience severe pre-treatment pain than those with metastases in junctional segments. Although further corroboration is needed, our results suggest that the mobility of the metastasis-bearing spinal section could be added to the existing list of predictors that aid clinicians in identifying patients that will benefit from closer follow-up or early intervention.

Is the Spinal Instability Neoplastic Score Accurate and Reliable in Predicting Vertebral Compression Fractures for Spinal Metastasis? A Systematic Review and Qualitative Analysis

Spinal metastases can present with varying degrees of mechanical instability. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic-related instability while helping to guide referrals among oncology specialists. Some previous papers suggested that the SINS was accurate and reliable, while others disagreed with this opinion. We performed a systematic review regarding the SINS to evaluate its accuracy and precision in predicting vertebral compression fractures (VCFs). The 21 included studies investigated a total of 2118 patients. Thirteen studies dealt with the accuracy of SINS to predict post-radiotherapy VCFs, and eight dealt with the precision. Among 13 studies, 11 agreed that the SINS categories showed statistically significant accuracy in predicting VCF. Among eight studies, body collapse was effective for predicting VCFs in six studies, and alignment and bone lesion in two studies. Location has no statistical significance in predicting VCFs in any of the eight studies. The precision of SINS categories was substantial to excellent in six of eight studies. Among the six components of the SINS, the majority of the included studies reported that location showed near perfect agreement; body collapse, alignment, and posterolateral involvement showed moderate agreement; and bone lesion showed fair agreement. Bone lesion showed significant accuracy in predicting VCFs in half of eight studies, but displayed fair reliability in five of seven studies. Although location was indicated as having near perfect reliability, the component showed no accuracy for predicting VCFs in any of the studies and deleting or modifying the item needs to be considered. The SINS system may be accurate and reliable in predicting the occurrence of post-radiotherapy VCFs for spinal metastasis. Some components seem to be substantially weak and need to be revised.

The Neurology-Stability-Epidural compression assessment: A new score to establish the need for surgery in spinal metastases

OBJECTIVE

The aim of this study was to translate new evidence about management of spinal metastases in a practical and reliable score for surgeons, radiation oncologists and oncologists, able to establish the need for surgery regardless the available technology and settings.

PATIENTS AND METHODS

Three main items were identified and graded: Neurological status (0-5 points), Stability of the spine according to the Spinal Instability Neoplastic Score (SINS) Score (0-5 points), and Epidural compression according to the Epidural Spinal Cord Compression (ESCC) scale (0-3 points). Patients were considered suitable for surgery with ASA score < 4 and ECOG score <3. A retrospective clinical validation of the NSE score was made on 145 patients that underwent surgical or non surgical treatment.

RESULTS

Agreement between the undertaken treatment and the score (88.3% of patients), resulted in a strong association with improvement or preservation of clinical status (neurological functions and mechanical pain) (p < 0.001) at 3 and 6 months. In the non-agreement group no association was recorded at the 3 and 6 months follow-up (p 0.486 and 0.343 for neurological functions, 0.063 and 0.858 for mechanical pain).

CONCLUSION

Functional outcomes of the study group showed that the proposed NSE score could represent a practical and reliable tool to establish the need for surgery. Agreement between the score and the performed treatments resulted in better clinical outcomes, when compared with patients without agreement. Further validation is needed with a larger number of patients and to assess reproducibility among surgeons, radiation oncologists, and oncologists.

Impact of body fat distribution and sarcopenia on the overall survival in patients with spinal metastases receiving radiotherapy treatment: a prospective cohort study

Introduction: An increasing number of patients is diagnosed with spinal metastases due to elevated cancer incidence and improved overall survival. Patients with symptomatic spinal bone metastases often receive radiotherapy with or without surgical stabilisation. Patients with a life expectancy of less than 3 months are generally deemed unfit for surgery, therefore adequate pre-treatment assessment of life expectancy is necessary. The aim of this study was to assess new factors associated with overall survival for this category of patients.Patients and methods: Patients who received radiotherapy for thoracic or lumbar spinal metastases from June 2013 to December 2016 were included in this study. The pre-treatment planning CT for radiotherapy treatment was used to assess the patient's visceral fat area, subcutaneous fat area, total muscle area and skeletal muscle density on a single transverse slice at the L3 level. The total muscle area was used to assess sarcopenia. Furthermore, data were collected on age, sex, primary tumour, Karnofsky performance score, medical history, number of bone metastases, non-bone metastases and neurological symptoms. Univariable and multivariable cox regressions were performed to determine the association between our variables of interest and the survival at 90 and 365 days.Results: A total of 310 patients was included. The median age was 67 years. Overall survival rates for 90 and 365 days were 71% and 36% respectively. For 90- and 365-day survival, the Karnofsky performance score, muscle density and primary tumour were independently significantly associated. The visceral or subcutaneous fat area and their ratio and sarcopenia were not independently associated with overall survival.Conclusions: Of the body morphology, only muscle density was statistically significant associated with overall survival after 90 and 365 days in patients with spinal bone metastases. Body fat distribution was not significantly associated with overall survival.

The clinical utility of the Spinal Instability Neoplastic Score (SINS) system in spinal epidural metastases: a retrospective study

STUDY DESIGN

A retrospective study.

OBJECTIVES

This study assessed the clinical utility of the Spinal Instability Neoplastic Score (SINS) in relation to the surgical treatment of spinal epidural metastasis and factors important for surgical decision-making. These factors include epidural spinal cord compression (ESCC), patient prognosis and neurologic status.

SETTING

Queen Elizabeth II Health Sciences Centre, Halifax, Canada.

METHODS

We identified 285 patients with spinal metastatic disease. Data were extracted through a retrospective review. SINS and ESCC were scored based on CT and MRI, respectively.

RESULTS

Patients were grouped into stable (35%), potentially unstable (52%), and unstable (13%) groups. The overall incidence of metastatic spinal deformity was 9%. Surgical interventions were performed in 21% of patients, including decompression and instrumented fusion (70%), decompression alone (17%), percutaneous vertebral augmentation (9%), and instrumented vertebral augmentation (5%). The use of spinal instrumentation was significantly associated with unstable SINS (p = 0.005). Grade 3 ESCC was also significantly associated with unstable SINS (p < 0.001). Kaplan-Meier analysis revealed that SINS was not a predictor of survival (p = 0.98). In the radiotherapy-alone group, a significant proportion of patients with potentially unstable SINS (30%) progressed into unstable SINS category at an average 364 ± 244 days (p < 0.001).

CONCLUSION

This study demonstrated that more severe categories of SINS were associated with higher degrees of ESCC, and surgical interventions were more often utilized in this group with more frequent placement of spinal instrumentation. Although SINS did not predict patient prognosis, it correlates with the progression of metastatic instability in patients treated with radiotherapy.

Surgical or Radiation Therapy for the Treatment of Cervical Spine Metastases: Results From the Epidemiology, Process, and Outcomes of Spine Oncology (EPOSO) Cohort

STUDY DESIGN

Ambispective cohort study design.

OBJECTIVES

Cervical spine metastases have distinct clinical considerations. The aim of this study was to determine the impact of surgical intervention (± radiotherapy) or radiotherapy alone on health-related quality of life (HRQOL) outcomes in patients treated for cervical metastatic spine tumours.

METHODS

Patients treated with surgery and/or radiotherapy for cervical spine metastases were identified from the Epidemiology, Process, and Outcomes of Spine Oncology (EPOSO) international multicentre prospective observational study. Demographic, diagnostic, treatment, and HRQOL (numerical rating scale [NRS] pain, EQ-5D (3L), SF-36v2, and SOSGOQ) measures were prospectively collected at baseline, 6 weeks, 3 months, and 6 months postintervention.

RESULTS

Fifty-five patients treated for cervical metastases were identified: 38 underwent surgery ± radiation and 17 received radiation alone. Surgically treated patients had higher mean spinal instability neoplastic scores compared with the radiation-alone group (13.0 vs 8.0, P < .001) and higher NRS pain scores and lower HRQOL scores compared to the radiation alone group (P < .05). From baseline to 6 months posttreatment, surgically treated patients demonstrated statistically significant improvements in NRS pain, EQ-5D (5L), and SOSGOQ2.0 scores compared with nonsignificant improvements in the radiotherapy alone group.

CONCLUSIONS

Surgically treated cervical metastases patients presented with higher levels of instability, worse baseline pain and HRQOL scores compared with patients who underwent radiotherapy alone. Significant improvements in pain and HRQOL were noted for those patients who received surgical intervention. Limited or no improvements were found in those treated with radiotherapy alone.

Population description and clinical response assessment for spinal metastases: part 2 of the SPIne response assessment in Neuro-Oncology (SPINO) group report

Background

Approximately 40% of metastatic cancer patients will develop spinal metastases. The current report provides recommendations for standardization of metrics used for spinal oncology patient population description and outcome assessment beyond local control endpoints on behalf of the SPIne response assessment in Neuro-Oncology (SPINO) group.

Methods

The SPINO group survey was conducted in order to determine the preferences for utilization of clinician-based and patient-reported outcome measures for description of patients with spinal metastases. Subsequently, ClinicalTrials.gov registry was searched for spinal oncology clinical trials, and measures for patient description and outcome reporting were identified for each trial. These two searches were used to identify currently used descriptors and instruments. A literature search was performed focusing on the measures identified in the survey and clinical trial search in order to assess their validity in the metastatic spinal tumor patient population. References for this manuscript were identified through PubMed and Medline searches.

Results

Published literature, expert survey, and ongoing clinical trials were used to synthesize recommendations for instruments for reporting of spinal stability, epidural tumor extension, neurological and functional status, and symptom severity.

Conclusions

Accurate description of patient population and therapy effects requires a combination of clinician-based and patient-reported outcome measures. The current report provides international consensus recommendations for the systematic reporting of patient- and clinician-reported measures required to develop trials applicable to surgery for spinal metastases and postoperative spine stereotactic body radiotherapy (SBRT).

Essential Concepts for the Management of Metastatic Spine Disease: What the Surgeon Should Know and Practice

STUDY DESIGN

Literature review.

OBJECTIVE

To provide an overview of the recent advances in spinal oncology, emphasizing the key role of the surgeon in the treatment of patients with spinal metastatic tumors.

METHODS

Literature review.

RESULTS

Therapeutic advances led to longer survival times among cancer patients, placing significant emphasis on durable local control, optimization of quality of life, and daily function for patients with spinal metastatic tumors. Recent integration of modern diagnostic tools, precision oncologic treatment, and widespread use of new technologies has transformed the treatment of spinal metastases. Currently, multidisciplinary spinal oncology teams include spinal surgeons, radiation and medical oncologists, pain and rehabilitation specialists, and interventional radiologists. Consistent use of common language facilitates communication, definition of treatment indications and outcomes, alongside comparative clinical research. The main parameters used to characterize patients with spinal metastases include functional status and health-related quality of life, the spinal instability neoplastic score, the epidural spinal cord compression scale, tumor histology, and genomic profile.

CONCLUSIONS

Stereotactic body radiotherapy revolutionized spinal oncology through delivery of durable local tumor control regardless of tumor histology. Currently, the major surgical indications include mechanical instability and high-grade spinal cord compression, when applicable, with surgery providing notable improvement in the quality of life and functional status for appropriately selected patients. Surgical trends include less invasive surgery with emphasis on durable local control and spinal stabilization.

Outcomes in the radiosurgical management of metastatic spine disease

Purpose

Stereotactic body radiation therapy (SBRT) is a common treatment option for patients with metastatic tumors of the spine. The optimal treatment-, tumor-, and patient-specific characteristics necessary to achieve durable outcomes remain less well understood given the heterogeneous nature of the patient population this modality typically serves. The objective of this analysis was to better understand the determinants underlying SBRT spine treatment outcomes.

Methods and Materials

A total of 127 patients with 287 spine tumors were treated between March 2010 and May 2015. The median total doses for single-fraction and hypofractionated courses of treatment were 16 Gy (range, 16-20 Gy) and 24 Gy (range, 16-40 Gy), respectively. Radiologic local control and numeric pain score data were measured, and univariate and multivariate analyses were done to determine factors predictive of treatment response.

Results

Median follow-up was 5.9 months (range, 1-61 months). Radiologic local control was achieved in 84.7% of patients at 6 months and in 74.7% of patients at 1 year. Local control was found to be affected by the Spinal Instability Neoplastic Score, and was worse in patients with scores ≥7 (hazard ratio [HR]: 4.25; 95% confidence interval [CI], 1.57-11.51). Patients who required upfront surgical intervention to alleviate spinal cord compression, address mechanical spinal instability, or both had worse local control than those who did not require surgery (HR: 2.32; 95% CI, 1.04-5.17). Patients treated with a hypofractionated course compared with a single fraction had worse radiologic local control (HR: 2.63; 95% CI, 1.27-5.45). No patients developed radiation-induced myelitis after treatment, and the vertebral compression fracture rate was 9.1% after SBRT.

Conclusions

Patients with potentially unstable spines or needing upfront spinal surgery before SBRT are less likely to achieve durable radiologic local control. Additionally, patients treated with single-fraction regimens have improved local control compared with those treated with hypofractionated radiation.

The Role of Prognostic Scoring Systems in Assessing Surgical Candidacy for Patients With Vertebral Metastasis: A Narrative Review

STUDY DESIGN

Narrative review.

OBJECTIVES

To review the relevant literature regarding scoring systems for vertebral metastases and quantify their role in contemporary orthopedic practice.

METHODS

A literature search of PubMed, Google Scholar, and Embase was performed on February 7, 2017. Eight scoring systems were selected for detailed review-7 of which were scores focused solely on patient prognosis (Tokuhashi, Tomita, Bauer, Oswestry Spinal Risk Index, Van der Linden, Rades, and Katagiri). The eighth system reviewed was the Spinal Instability Neoplastic Score, which examines for impending spinal instability in patients with vertebral metastases and represents a novel approach compared with hitherto scoring systems.

RESULTS

The Bauer and Oswestry Spinal Risk Index have the most accurate prognostic predictive ability, with the newer Oswestry Spinal Risk Index being favored by the contemporary literature as it demands less investigation and is therefore more readily accessible. There was a growing trend in studies designed to customize scoring systems for individual cancer pathological subtypes. The Spinal Instability Neoplastic Score shows good reliability for predicting instability among surgeons and oncologists.

CONCLUSIONS

The increased understanding of cancer pathology and subsequent development of customized treatments has led to prolonged survival. For patients with vertebral metastases, this affects surgical candidacy not only on the basis of prognosis but also provides prolonged opportunity for the development of spinal instability. Scoring systems have a useful guidance role in these deciding for/against surgical intervention, but in order to remain contemporary ongoing review, development, and revalidation is mandatory.

Management of extranodal lymphoma of the spine: a study of 30 patients

Extranodal lymphoma of the spine is often a late manifestation of systemic disease, and may result in symptoms of pain, neurologic compromise or spinal instability. Symptomatic relief is generally achieved by radiotherapy alone, but is not sufficient in addressing spinal instability. The indications for surgery remain controversial, but may be required for spinal stabilization, or refractory disease. Currently, there is a lack of studies that compare the indications and clinical outcomes of patients receiving surgical and nonsurgical management of spinal extranodal lymphoma. Medical records of 30 patients seen from March 2006 to August 2015, with histologically confirmed spinal lymphoma, were retrospectively reviewed. Demographic information, clinical factors, imaging, treatment and clinical outcomes were recorded. 19 patients were treated surgically and 11 nonsurgically (i.e., chemotherapy, radiation or combination). Surgery was performed for emergent neurological deterioration, mechanical stabilization, refractoriness to medical management or to perform an open biopsy for pathological diagnosis. Among those treated surgically, significantly fewer patients could carry on normal activities (KPS <70) at baseline, compared with those treated nonsurgically. However, there were no significant differences regarding pain medication use, functional status at 1 year, or mean survival (87.6 months) between groups. Surgery for extranodal lymphoma may be required in specific cases, resulting in favorable and similar outcomes compared with nonsurgical management.

Impact of the Spinal Instability Neoplastic Score on Surgical Referral Patterns and Outcomes

Background

The Spinal Instability Neoplastic Score (sins) was developed to identify patients with spinal metastases who may benefit from surgical consultation. We aimed to assess the distribution of sins in a population-based cohort of patients undergoing palliative spine radiotherapy (rt) and referral rates to spinal surgery pre-rt. Secondary outcomes included referral to a spine surgeon post-rt, overall survival, maintenance of ambulation, need for re-intervention, and presence of spinal adverse events.

Methods

We retrospectively reviewed ct simulation scans and charts of consecutive patients receiving palliative spine rt between 2012 and 2013. Data were analyzed using Student's t-test, Chi-squared, Fisher's exact, and Kaplan-Meier log-rank tests. Patients were stratified into low (<7) and high (≥7) sins groups.

Results

We included 195 patients with a follow-up of 6.1 months. The median sins was 7. The score was 0 to 6 (low, no referral recommended), 7 to 12 (intermediate, consider referral), and 13 to 18 (high, referral suggested) in 34%, 59%, and 7% of patients, respectively. Eleven patients had pre-rt referral to spine surgery, with a surgery performed in 0 of 1 patient with sins 0 to 6, 1 of 7 with sins 7 to 12, and 1 of 3 with sins 13 to 18. Seven patients were referred to a surgeon post-rt with salvage surgery performed in two of those patients. Primary and secondary outcomes did not differ between low and high sins groups.

Conclusion

Higher sins was associated with pre-rt referral to a spine surgeon, but most patients with high sins were not referred. Higher sins was not associated with shorter survival or worse outcome following rt.

Patient-reported outcomes after surgical stabilization of spinal tumors: symptom-based validation of the Spinal Instability Neoplastic Score (SINS) and surgery

BACKGROUND CONTEXT

Neoplastic spinal instability is movement-related pain or neurologic compromise under physiologic loads with the Spinal Instability Neoplastic Score (SINS) developed to facilitate diagnosis. There is a paucity of evidence that mechanical instability correlates with patient-reported symptoms and that surgical stabilization significantly improves these patient-reported outcomes (PROs).

PURPOSE

The objective of this study was to determine if SINS correlates with patient-reported preoperative pain and disability, and if surgical stabilization significantly improves PRO.

STUDY DESIGN

A single-institution prospective cohort study was carried out.

PATIENT SAMPLE

A total of 131 patients who underwent stabilization for metastatic spinal tumor treatment between July 2014 and August 2016 were included.

OUTCOMES MEASURES

Preoperative baseline and mean difference in perioperative PROs as assessed by the Brief Pain Inventory (BPI) and MD Anderson Symptom Inventory (MDASI) were the outcome measures.

METHODS

The SINS was analyzed as a continuous, ordinal, and categorical variable (Stable: 0-6, Indeterminate: 7-12, Unstable: 13-18). Statistical analysis was performed using Spearman rank coefficient (rho), the Kruskal-Wallis test, and an extension of the Cochran-Armitage trend test. The SINS and association between the mean differences in post- and preoperative PRO scores was analyzed using the Wilcoxon signed-rank test.

RESULTS

There was a statistically significant positive correlation between increasing SINS and severity of preoperative pain with BPI average pain (rho=0.20; p=.03) and MDASI pain (rho=0.19; p=.03). Increasing SINS correlated with severity of preoperative disability with BPI walking (rho=0.19; p=.04), MDASI activity (rho=0.24; p=.006), and MDASI walking (rho=0.20; p=.03). Similar associations were noted when SINS was analyzed as an ordinal categorical variable. Stabilization significantly improved nearly all PRO measures for patients with indeterminate and unstable SINS. Significant correlations persisted when controlling for neurologic status and were not affected based on the technique of surgical stabilization used.

CONCLUSIONS

Patient-related outcome-based validation of SINS confirms this scoring system for diagnosing neoplastic spinal instability and provides surgeons with a tool to determine which patients will benefit from stabilization. Surgical stabilization of cancer patients with SINS consistent with mechanical instability provides significant reduction in pain and improves patient mobility independent of neurologic status and stabilization technique.

Spinal Instability Neoplastic Score (SINS): Reliability Among Spine Fellows and Resident Physicians in Orthopedic Surgery and Neurosurgery

STUDY DESIGN

Reliability analysis.

OBJECTIVES

The Spinal Instability Neoplastic Score (SINS) was developed for assessing patients with spinal neoplasia. It identifies patients who may benefit from surgical consultation or intervention. It also acts as a prognostic tool for surgical decision making. Reliability of SINS has been established for spine surgeons, radiologists, and radiation oncologists, but not yet among spine surgery trainees. The purpose of our study is to determine the reliability of SINS among spine residents and fellows, and its role as an educational tool.

METHODS

Twenty-three residents and 2 spine fellows independently scored 30 de-identified spine tumor cases on 2 occasions, at least 6 weeks apart. Intraclass correlation coefficient (ICC) measured interobserver and intraobserver agreement for total SINS scores. Fleiss's kappa and Cohen's kappa analysis evaluated interobserver and intraobserver agreement of 6 component subscores (location, pain, bone lesion quality, spinal alignment, vertebral body collapse, and posterolateral involvement of spinal elements).

RESULTS

Total SINS scores showed near perfect interobserver (0.990) and intraobserver (0.907) agreement. Fleiss's kappa statistics revealed near perfect agreement for location; substantial for pain; moderate for alignment, vertebral body collapse, and posterolateral involvement; and fair for bone quality (0.948, 0.739, 0.427, 0.550, 0.435, and 0.382). Cohen's kappa statistics revealed near perfect agreement for location and pain, substantial for alignment and vertebral body collapse, and moderate for bone quality and posterolateral involvement (0.954, 0.814, 0.610, 0.671, 0.576, and 0.561, respectively).

CONCLUSIONS

The SINS is a reliable and valuable educational tool for spine fellows and residents learning to judge spinal instability.

Diagnostic algorithm, prognostic factors and surgical treatment of metastatic cancer diseases of the long bones and spine

Oncological management of skeletal metastases has changed dramatically in the last few decades. A significant number of patients survive for many years with their metastases.

Surgeons are more active and the technical repertoire is broader, from plates to intramedullary devices to (tumour) endoprostheses.

The philosophy of treatment should be different in the case of a trauma-related fracture and a pathological fracture. A proper algorithm for establishing a diagnosis and evaluation of prognostic factors helps in planning the surgical intervention.

The aim of palliative surgery is usually to eliminate pain and to allow the patient to regain his/her mobility as well as to improve the quality of life through minimally invasive techniques using life-long durable devices.

In a selected group of patients with an oncologically controlled primary tumour site and a solitary bone metastasis with positive prognostic factors, which meet the criteria for radical excision (approximately 10% to 15% of the cases), a promising three to five years of survival may be achieved, especially in cases of metastases from breast and kidney cancer.

Spinal metastases require meticulous evaluation because decisions on treatment mostly depend on the tumour type, segmental stability, the patient’s symptoms and general state of health.

Advanced radiotherapy combined with minimally invasive surgical techniques (minimally invasive stabilisation and separation surgery) provides durable local control with a low complication rate in a number of patients.

Cite this article: EFORT Open Rev 2017;2:372-381.

The spine instability neoplastic score (SINS) in the assessment of response to radiotherapy for bone metastases

BACKGROUND

Vertebral metastases are often causing pain and spine instability. Radiotherapy is of significant benefit for painful spine metastases but the response can be very variable. The spine instability neoplastic score (SINS) is a recent classification system for diagnosis of spinal instability caused by vertebral metastases. We analysed the degree of pain relief, the need of drug therapy and the imaging features and the SINS before and after radiotherapy. In particular, we investigated the possible correlation of spine instability defined by pre-treatment SINS with pretreatment pain and with response to radiotherapy.

MATERIAL/METHODS

This study included 121 patients with spine metastases treated with palliative 3D conformal radiotherapy. Pain "at rest" and "breakthrough pain", need for drug therapy in terms of "anti-inflammatory", "weak opioid", "strong opioid", imaging studies and SINS were assessed before and after radiotherapy. Statistical analysis was performed by the correlation coefficient of Spearman and Kruskal-Wallis test.

RESULTS

Pain relief after radiotherapy was observed in 50.4 and 57.8% of patients in terms of pain at rest and breakthrough pain, respectively. The correlation between pain before radiotherapy and SINS was not statistically significant for both pain at rest (p = 0.4) and breakthrough pain (p = 0.49). The correlation between pain response after radiotherapy and SINS was statistically significant for both pain at rest (p = 0.007) and breakthrough pain (p = 0.047).

DISCUSSION/CONCLUSION

The degree of instability, classified according to SINS, resulted to be predictive factor for pain response after radiotherapy. SINS might become a valid tool to identify those patients who can benefit the most from radiotherapy.

Prospective Evaluation of the Relationship Between Mechanical Stability and Response to Palliative Radiotherapy for Symptomatic Spinal Metastases

BACKGROUND

A substantial number of patients with spinal metastases experience no treatment effect from palliative radiotherapy. Mechanical spinal instability, due to metastatic disease, could be associated with failed pain control following radiotherapy. This study investigates the relationship between the degree of spinal instability, as defined by the Spinal Instability Neoplastic Score (SINS), and response to radiotherapy in patients with symptomatic spinal metastases in a multi-institutional cohort.

METHODS AND MATERIALS

The SINS of 155 patients with painful thoracic, lumbar, or lumbosacral metastases from two tertiary hospitals was calculated using images from radiotherapy planning CT scans. Patient-reported pain response, available for 124 patients, was prospectively assessed. Pain response was categorized, according to international guidelines, as complete, partial, indeterminate, or progression of pain. The association between SINS and pain response was estimated by multivariable logistic regression analysis, correcting for predetermined clinical variables.

RESULTS

Of the 124 patients, 16 patients experienced a complete response and 65 patients experienced a partial response. Spinal Instability Neoplastic Score was associated with a complete pain response (adjusted odds-radio [ORadj] 0.78; 95% confidence interval [CI] 0.62-0.98), but not with an overall pain response (ORadj 0.94; 95% CI 0.81-1.10).

CONCLUSIONS

A lower SINS, indicating spinal stability, is associated with a complete pain response to radiotherapy. This supports the hypothesis that pain resulting from mechanical spinal instability responds less well to radiotherapy compared with pain from local tumor activity. No association could be determined between SINS and an overall pain response, which might indicate that this referral tool is not yet optimal for prediction of treatment outcome.

IMPLICATIONS FOR PRACTICE

Patients with stable painful spinal metastases, as indicated by a Spinal Instability Neoplastic Score (SINS) of 6 or lower, can effectively be treated with palliative external beam radiotherapy. The majority of patients with (impending) spinal instability, as indicated by a SINS score of 7 or higher, will achieve a (partial) response after palliative radiotherapy; however, some patients might require surgical intervention. Therefore, it is recommended to refer patients with a SINS score of 7 or higher to a spine surgeon to evaluate the need for surgical intervention.

The Spinal Instability Neoplastic Score: Impact on Oncologic Decision-Making

STUDY DESIGN

Systematic literature review.

OBJECTIVE

To address the following questions in a systematic literature review: 1. How is spinal neoplastic instability defined or classified in the literature before and after the introduction of the Spinal Instability Neoplastic Score (SINS)? 2. How has SINS affected daily clinical practice? 3. Can SINS be used as a prognostic tool?

SUMMARY OF BACKGROUND DATA

Spinal neoplastic-related instability was defined in 2010 and simultaneously SINS was introduced as a novel tool with criteria agreed upon by expert consensus to assess the degree of spinal stability.

METHODS

PubMed, Embase, and clinical trial databases were searched with the key words "spinal neoplasm," "spinal instability," "spinal instability neoplastic score," and synonyms. Studies describing spinal neoplastic-related instability were eligible for inclusion. Primary outcomes included studies describing and/or defining neoplastic-related instability, SINS, and studies using SINS as a prognostic factor.

RESULTS

The search identified 1414 articles, of which 51 met the inclusion criteria. No precise definition or validated assessment tool was used specific to spinal neoplastic-related instability prior to the introduction of SINS. Since the publication of SINS in 2010, the vast majority of the literature regarding spinal instability has used SINS to assess or describe instability. Twelve studies specifically investigated the prognostic value of SINS in patients who underwent radiotherapy or surgery.

CONCLUSION

No consensus could be determined regarding the definition, assessment, or reporting of neoplastic-related instability before introduction of SINS. Defining spinal neoplastic-related instability and the introduction of SINS have led to improved uniform reporting within the spinal neoplastic literature. Currently, the prognostic value of SINS is controversial.

LEVEL OF EVIDENCE

N/A.

Spine Instability Neoplastic Score: agreement across different medical and surgical specialties

BACKGROUND CONTEXT

Spinal instability is an acknowledged complication of spinal metastases; in spite of recent suggested criteria, it is not clearly defined in the literature.

PURPOSE

This study aimed to assess intra and interobserver agreement when using the Spine Instability Neoplastic Score (SINS) by all physicians involved in its management.

STUDY DESIGN

Independent multicenter reliability study for the recently created SINS, undertaken with a panel of medical oncologists, neurosurgeons, radiologists, orthopedic surgeons, and radiation oncologists, was carried out.

PATIENT SAMPLE

Ninety patients with biopsy-proven spinal metastases and magnetic resonance imaging, reviewed at the multidisciplinary tumor board of our institution, were included.

OUTCOME MEASURES

Intraclass correlation coefficient (ICC) was used for SINS score agreement. Fleiss kappa statistic was used to assess agreement on the location of the most affected vertebral level; agreement on the SINS category ("stable," "potentially stable," or "unstable"); and overall agreement with the classification established by tumor board.

METHODS

Clinical data and imaging were provided to 83 specialists in 44 hospitals across 14 Spanish regions. No assessment criteria were pre-established. Each clinician assessed the SINS score twice, with a minimum 6-week interval. Clinicians were blinded to assessments made by other specialists and to their own previous assessment. Subgroup analyses were performed by clinicians' specialty, experience (≤7, 8-13, ≥14 years), and hospital category (four levels according to size and complexity). This study was supported by Kovacs Foundation.

RESULTS

Intra and interobserver agreement on the location of the most affected levels was "almost perfect" (κ>0.94). Intra-observer agreement on the SINS score was "excellent" (ICC=0.77), whereas interobserver agreement was "moderate" (ICC=0.55). Intra-observer agreement in SINS category was "substantial" (k=0.61), whereas interobserver agreement was "moderate" (k=0.42). Overall agreement with the tumor board classification was "substantial" (κ=0.61). Results were similar across specialties, years of experience, and hospital category.

CONCLUSIONS

Agreement on the assessment of metastatic spine instability is moderate. The SINS can help improve communication among clinicians in oncology care.

Consensus building in metastatic spine disease

Arana E, Kovacs FM, Royuela A, Asenjo B, Pérez-Ramírez Ú, Zamora J, the Spanish Back Pain Research Network Task Force for the Improvement of Inter-Disciplinary Management of Spinal Metastasis. Spine Instability Neoplastic Score: agreement across different medical and surgical specialties. Spine J 2016;16:591-9 (in this issue).

Prediction of skeletal-related events in patients with non-small cell lung cancer

PURPOSE

Advanced lung cancer frequently causes bone metastasis which can be associated with skeletal-related events (SREs) that may cause significant deterioration of the patient's quality of life (QoL). The Spinal Instability Neoplastic Score (SINS) can be used to assist in standardizing evaluations of neoplastic spinal instability between spinal and non-spine surgeons. This research investigated the association between SREs and SINS for patients with non-small cell lung cancer (NSCLC).

METHODS

Between 2009 and 2013, 47 patients with NSCLC who were diagnosed with bone metastasis were classified using SINS into either a stable group (SINS, 0-6 points) or unstable group (SINS, 7-18 points). The primary endpoint was time from diagnosis of metastasis to SREs. Secondary endpoints included tumor type and epidermal growth factor receptor (EGFR) mutational status. SREs were defined as spinal compression, pathologic fracture, spinal surgery, and hypercalcemia.

RESULTS

Patients included 37 cases of adenocarcinoma and 10 cases of squamous cell carcinoma. Mean follow-up time was 10.2 ± 13.7 months. SRE incidence was 15.0 % (3/20) in the stable group versus 44.4 % (12/27) in the unstable group (p = 0.048). A Cox regression model revealed that an EGFR-positive mutational status (hazard ratio [HR] = 0.15, 95 % CI, 0.030.71; p = 0.017) or good spinal stability (HR = 0.49; 0.08-0.99; p = 0.049) were favorable prognostic factors.

CONCLUSION

The incidence of SREs was significantly lower in NSCLC patients with better spinal stability as determined by SINS, which was a good prediction tool for SREs from bone metastasis. The lower incidence of SREs in EGFR-positive patients suggests tumor biology should be considered when predicting SREs.

Is there a relationship between spinal instability in neoplastic disease and Tokuhashi scoring system?

Spinal instability neoplastic score (SINS) classification evaluates spinal stability by adding together six radiographic and clinical components. The objective of this study was to verify the association between SINS and Tokuhashi scoring system (TSS) score. Fifty-eight patients with vertebral metastases were admitted from 2010 to 2014 at Hospital do Servidor Público Estadual de São Paulo. They were evaluated according to their SINS and Tokuhashi SS score. Fourteen patients (24.13 %) scored from 0 to 6 points (stable spine), 37 (63.79 %) scored from 7 to 12 (potentially unstable), and 7 (12.06 %) scored from 13 to 18 (unstable). In stable spine patients according to SINS, the mean TSS score was 9.2. In potentially unstable spine patients, the mean TSS score was 8.24. In unstable spine patients, mean TSS score was 6.28. There was a statistically significant difference of the TSS score between stable and unstable patients. After evaluating TSS score in each patient, the worse the SINS, the worse was also the TSS score.

The Effect of Introducing the Spinal Instability Neoplastic Score in Routine Clinical Practice for Patients With Spinal Metastases

BACKGROUND

Stable spinal metastases are effectively treated with radiotherapy, whereas unstable spinal metastases often need surgical fixation followed by radiotherapy for local control. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic related instability with the goal of helping to guide referrals among oncology specialists. We compare the average degree of spinal instability between patients with spinal metastases referred for surgery or for radiotherapy and evaluate whether this difference changed after introduction of the SINS in clinical practice.

METHODS

All patients with spinal metastases treated with palliative surgery or radiotherapy in the period 2009-2013 were identified in two spine centers. For all patients, the SINS was scored on pretreatment imaging. The SINS before and after introduction of the SINS in 2011 were compared within the surgical and radiotherapy group. Furthermore, the overall SINS was compared between the two groups.

RESULTS

The overall SINS was significantly higher in the surgical group, with a mean SINS of 10.7 (median 11) versus 7.2 (median 8) for the radiotherapy group. The mean SINS decreased significantly for both groups after introduction of the SINS in clinical practice from 11.2 to 10.3 in the surgical group and from 8.4 to 7.2 in the radiotherapy group.

CONCLUSION

The SINS differed significantly between patients treated with surgery or radiotherapy. The introduction of SINS led to a decrease in SINS score for both groups, suggesting that using SINS in metastatic spinal disease increases awareness for instability and may subsequently result in earlier referrals for surgical intervention.

IMPLICATIONS FOR PRACTICE

Spinal metastases can present with varying degrees of mechanical instability. Because unstable spinal metastases may respond insufficiently to palliative radiotherapy and can lead to loss of ambulation, timely detection and appropriate referral are important. The Spinal Instability Neoplastic Score (SINS) may help physicians caring for patients with metastasized disease to identify spinal instability before the onset of neurological deficits. In this study, it was shown that the introduction of SINS in routine practice led to a decrease in spinal instability in radiotherapy and surgical cohorts. The use of SINS may increase awareness of instability and subsequently result in earlier referrals.

Incidence, associated factors, and survival in metastatic spinal cord compression secondary to lung cancer

BACKGROUND CONTEXT

Bone metastasis (BM) occurs frequently in patients with lung cancer (LC). The most affected are the bones of the spine, increasing the risk of developing metastatic spinal cord compression (MSCC). Although MSCC is one of the most disabling complications, few studies have reported relevant results related to its frequency and prognosis among patients with LC.

PURPOSE

The purpose of this study was to determine the incidence and associated factors of the development of MSCC after BM with LC and its prognosis.

STUDY DESIGN/SETTING

This is a cohort study.

PATIENT SAMPLE

A cohort of 112 patients with BM because of LC, whose treatment was performed exclusively at the National Cancer Institute, was analyzed.

OUTCOME MEASURES

Study outcome measures included incidence of MSCC, factors associated with MSCC, and survival analysis.

METHODS

A cohort study was performed involving patients with BM because of LC diagnosed between 2007 and 2011. Clinical and sociodemographic data were extracted from the physical and electronic medical records because of initial diagnosis (up until December 2013). The association between the independent variables and the outcomes was performed by using crude and adjusted odds ratios (ORs), assuming 95% confidence intervals (CIs). For the exploratory evaluation between the independent variables and the time until the outcomes, Kaplan-Meier survival analysis was conducted. To identify if the differences between the curves were statistically significant, a log-tank test was calculated. A Cox multiple regression model, using the forward stepwise method, was applied, aiming to estimate the factors associated with time to death in the different exposure groups.

RESULTS

Of the 112 patients with BM, 31 (27.7%) developed MSCC. The univariate analysis showed that patients with three or more involved vertebrae revealed a 6.1 times greater risk of developing MSCC, compared with those with up to two metastatic vertebrae involved (OR: 6.1, 95% CI: 2.5-15.1, p<.001). Among the patients who developed MSCC, the median survival time was 4.4 months (95% CI: 1.5-7.3) and 4.7 months (95% CI: 3.5-5.9) in the patients without MSCC, not being a statistically significant difference (p=.19). After the occurrence of the MSCC, the median survival time was 2.8 months (95% CI: 1.4-4.1).

CONCLUSIONS

In this study, a high incidence of MSCC was observed in patients with BM. The study suggests that patients with three or more involved vertebrae per metastasis are more likely to develop MSCC. No alteration in the overall survival time was noticed among the patients with or without MSCC.

Vertebral compression fractures after spine irradiation using conventional fractionation in patients with metastatic colorectal cancer

Purpose

To evaluate the risk of vertebral compression fracture (VCF) after conventional radiotherapy (RT) for colorectal cancer (CRC) with spine metastasis and to identify risk factors for VCF in metastatic and non-metastatic irradiated spines.

Materials and Methods

We retrospectively reviewed 68 spinal segments in 16 patients who received conventional RT between 2009 and 2012. Fracture was defined as a newly developed VCF or progression of an existing fracture. The target volume included all metastatic spinal segments and one additional non-metastatic vertebra adjacent to the tumor-involved spines.

Results

The median follow-up was 7.8 months. Among all 68 spinal segments, there were six fracture events (8.8%) including three new VCFs and three fracture progressions. Observed VCF rates in vertebral segments with prior irradiation or pre-existing compression fracture were 30.0% and 75.0% respectively, compared with 5.2% and 4.7% for segments without prior irradiation or pre-existing compression fracture, respectively (both p < 0.05). The 1-year fracture-free probability was 87.8% (95% CI, 78.2-97.4). On multivariate analysis, prior irradiation (HR, 7.30; 95% CI, 1.31-40.86) and pre-existing compression fracture (HR, 18.45; 95% CI, 3.42-99.52) were independent risk factors for VCF.

Conclusion

The incidence of VCF following conventional RT to the spine is not particularly high, regardless of metastatic tumor involvement. Spines that received irradiation and/or have pre-existing compression fracture before RT have an increased risk of VCF and require close observation.

The current status and future of radiotherapy for spinal bone metastases

The management of spinal bone metastases is complex. In this review, the efficacy, methodology, and utilization of radiotherapy (RT) for spinal bone metastases are discussed. A number of randomized trials have evaluated the efficacy of 8 Gy, single-fraction RT for the palliation of painful bone metastases. However, RT for metastatic spinal cord compression has not been evaluated with respect to its optimal dose, palliative potential, or its ability to improve motor function. Two highly sophisticated RT techniques - stereotactic body RT (SBRT) and intensity-modulated RT (IMRT) - have recently been adapted for the treatment of spinal bone metastases, and both have the potential to achieve excellent control while minimizing acute and late toxicity. SBRT and IMRT are particularly well suited for the treatment of spinal bone metastases when they are localized or require re-irradiation, and may provide superior tumor control. Predicting the prognosis of patients with bone metastases and assessing spinal instability are both important when selecting the optimal RT method and deciding whether to perform surgery. The proper care of spinal bone metastases patients requires an interdisciplinary treatment approach.