Frequency of Screening Magnetic Resonance Imaging to Detect Occult Spinal Cord Compromise and to Prevent Neurological Deficit in Metastatic Castration-resistant Prostate Cancer

Impact of metastatic epidural spinal cord compression (MESCC) and pathological vertebral compression fracture (pVCF) in neurological and survival prognosis

BACKGROUND

Metastatic epidural spinal cord compression (MESCC) and pathological vertebral compression fractures (pVCF) are the most serious debilitating morbidities of spine metastases (SpMs) causing devastating neurological damages. The respective impact of these two metastasis-spreading entities on survival and on neurological damage is debated.

METHODS

A French prospective cohort study collected 279 consecutive patients presenting with SpMs between January 2017 and 2021. We compared 174 patients with MESCC and 105 patients with pVCF.

RESULTS

The median Overall Survival (OS) for the MESCC group was 13.4 months (SD 1.5) vs 19.2 months (SD 2.3) for pVCF patients (p = 0.085). Sixty-five patients (23.3 %) were operated on: 49/65 (75.4 %) in the MESCC group and 16/65 (15.2 %) in the pVCF group, p < 0.0001. At 6 months FU, in the MESCC group, 21/44 (45.4 %) of non-ambulatory patients at onset improved to ambulatory status (Frankel D-E) vs 10/13 (76.9 %) in the pVCF group (p = 0.007). In multivariable analysis with the Cox proportional hazard model, good ECOG-PS and SINS Score 7-12 [HR: 6.755, 95 % CI 2.40-19.00; p = 0.001] were good prognostic factors for preserved ambulatory neurological status. However, SpMs diagnosed synchronously with the primary tumor [HR: 0.397, 95 % CI 0.185-0.853; p = 0.018] and MESCC [HR: 0.058, 95 % CI 0.107-0.456; p = 0.007] were independent risk factors for impaired neurological function.

CONCLUSION

Contrary to pVCF, MESCC causes neurological damage. Nevertheless, neurological recovery remains possible. MESCC and pVCF have no impact on survival. The management of MESCC remains to be clarified and optimized to reduce neurological damage.

Epidemiology of spinal metastases, metastatic epidural spinal cord compression and pathologic vertebral compression fractures in patients with solid tumors: A systematic review

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The clinical incidence of spinal metastases is 15.67%, two thirds are metastases from breast-, prostate- or lung cancer.

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9.6% of patients with spinal metastases develop metastatic epidural spinal cord compression.

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1 out of 8 (12.6%) of patients with spinal metastases suffer of pathologic vertebral compression fractures.

Introduction

Spinal metastases (SM) are a frequent complication of cancer and may lead to pathologic vertebral compression fractures (pVCF) and/or metastatic epidural spinal cord compression (MESCC). Based on autopsy studies, it is estimated that about one third of all cancer patients will develop SM. These data may not provide a correct estimation of the incidence in clinical practice.

Objective

This systematic review (SR) aims to provide a more accurate estimation of the incidence of SM, MESCC and pVCF in a clinical setting.

Methods

We performed a SR of papers regarding epidemiology of SM, pVCF, and MESCC in patients with solid tumors conform PRISMA guidelines. A search was conducted in the PubMed and Web of Science database using the terms epidemiology, prevalence, incidence, global burden of disease, cost of disease, spinal metastas*, metastatic epidural spinal cord compression, pathologic fracture, vertebral compression fracture, vertebral metastas* and spinal neoplasms. Papers published between 1975 and august 2021 were included. Quality was evaluated by the STROBE criteria.

Results

While 56 studies were included, none of them reports the actual definition used for MESCC and pVCF, inevitably introducing heterogenity. The overall cumulative incidence of SM and MESCC is 15.67% and 2.84% respectively in patients with a solid tumor. We calculated a mean cumulative incidence in patients with SM of 9.56% (95% CI 5.70%-13.42%) for MESCC and 12.63% (95% CI 7.00%-18.25%) for pVCF. Studies show an important delay between onset of symptoms and diagnosis.

Conclusions

While the overall cumulative incidence for clinically diagnosed SM in patients with a solid tumor is 15.67%, autopsy studies reveal that SM are present in 30% by the time they die, suggesting underdiagnosing of SM. Approximately 1 out of 10 patients with SM will develop MESCC and another 12.6% will develop a pVCF. Understanding these epidemiologic data, should increase awareness for first symptoms, allowing early diagnosis and subsequent treatment, thus improving overall outcome.

Observation versus screening spinal MRI and pre-emptive treatment for spinal cord compression in patients with castration-resistant prostate cancer and spinal metastases in the UK (PROMPTS): an open-label, randomised, controlled, phase 3 trial

BACKGROUND

Early diagnosis of malignant spinal cord compression (SCC) is crucial because pretreatment neurological status is the major determinant of outcome. In metastatic castration-resistant prostate cancer, SCC is a clinically significant cause of disease-related morbidity and mortality. We investigated whether screening for SCC with spinal MRI, and pre-emptive treatment if radiological SCC (rSCC) was detected, reduced the incidence of clinical SCC (cSCC) in asymptomatic patients with metastatic castration-resistant prostate cancer and spinal metastasis.

METHODS

We did a parallel-group, open-label, randomised, controlled, phase 3, superiority trial. Patients with metastatic castration-resistant prostate cancer were recruited from 45 National Health Service hospitals in the UK. Eligible patients were aged at least 18 years, with an Eastern Co-operative Oncology Group performance status of 0-2, asymptomatic spinal metastasis, no previous SCC, and no spinal MRI in the past 12 months. Participants were randomly assigned (1:1), using a minimisation algorithm with a random element (balancing factors were treatment centre, alkaline phosphatase [normal vs raised, with the upper limit of normal being defined at each participating laboratory], number of previous systemic treatments [first-line vs second-line or later], previous spinal treatment, and imaging of thorax and abdomen), to no MRI (control group) or screening spinal MRI (intervention group). Serious adverse events were monitored in the 24 h after screening MRI in the intervention group. Participants with screen-detected rSCC were offered pre-emptive treatment (radiotherapy or surgical decompression was recommended per treating physician's recommendation) and 6-monthly spinal MRI. All patients were followed up every 3 months, and then at month 30 and 36. The primary endpoint was time to and incidence of confirmed cSCC in the intention-to-treat population (defined as all patients randomly assigned), with the primary timepoint of interest being 1 year after randomisation. The study is registered with ISRCTN, ISRCTN74112318, and is now complete.

FINDINGS

Between Feb 26, 2013, and April 25, 2017, 420 patients were randomly assigned to the control (n=210) or screening MRI (n=210) groups. Median age was 74 years (IQR 68 to 79), 222 (53%) of 420 patients had normal alkaline phosphatase, and median prostate-specific antigen concentration was 48 ng/mL (IQR 17 to 162). Screening MRI detected rSCC in 61 (31%) of 200 patients with assessable scans in the intervention group. As of data cutoff (April 23, 2020), at a median follow-up of 22 months (IQR 13 to 31), time to cSCC was not significantly improved with screening (hazard ratio 0·64 [95% CI 0·37 to 1·11]; Gray's test p=0·12). 1-year cSCC rates were 6·7% (95% CI 3·8-10·6; 14 of 210 patients) for the control group and 4·3% (2·1-7·7; nine of 210 patients) for the intervention group (difference -2·4% [95% CI -4·2 to 0·1]). Median time to cSCC was not reached in either group. No serious adverse events were reported within 24 h of screening.

INTERPRETATION

Despite the substantial incidence of rSCC detected in the intervention group, the rate of cSCC in both groups was low at a median of 22 months of follow-up. Routine use of screening MRI and pre-emptive treatment to prevent cSCC is not warranted in patients with asymptomatic castration-resistant prostate cancer with spinal metastasis.

FUNDING

Cancer Research UK.

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.

Progressive computed tomography (CT) appearances preceding malignant spinal cord compression (MSCC) in men with castration-resistant prostate cancer

AIM

To test the hypothesis that computed tomography (CT)-based signs might precede symptomatic malignant spinal cord compression (MSCC) in men with metastatic castration-resistant prostate cancer (mCRPC).

MATERIALS AND METHODS

A database was used to identify suitable mCRPC patients. Staging CT images were retrospectively reviewed for signs preceding MSCC. Signs of malignant paravertebral fat infiltration and epidural soft-tissue disease were defined and assessed on serial CT in 34 patients with MSCC and 58 control patients. The presence and evolution of the features were summarized using descriptive statistics.

RESULTS

In MSCC patients, CT performed a median of 28 days prior to the diagnostic magnetic resonance imaging (MRI) demonstrated significant epidural soft tissue in 28 (80%) patients. The median time to MSCC from a combination of overt malignant paravertebral and epidural disease was 2.7 (0-14.6) months. Conversely, these signs were uncommon in the control cohort.

CONCLUSIONS

Significant malignant paravertebral and/or epidural disease at CT precede MSCC in up to 80% of mCRPC patients and should prompt closer patient follow-up and consideration of early MRI evaluation. These CT-based features require further prospective validation.

MRI and neurological findings in patients with spinal metastases

BACKGROUND

Magnetic resonance imaging (MRI) is the recommended primary investigation method for metastatic spinal cord compression (MSCC). Initiating treatment before the development of motor deficits is essential to preserve neurological function. However, the relationship between MRI-assessed grades of spinal metastatic disease and neurological status has not been widely investigated.

PURPOSE

To analyze the association between neurological function and MRI-based assessment of the extent of spinal metastases using two different grading systems.

MATERIAL AND METHODS

A total of 284 patients admitted to our institution for initial radiotherapy or surgery for symptomatic spinal metastases were included in the study. Motor and sensory deficits were categorized according to the Frankel classification system. Pre-treatment MRI evaluations of the entire spine were scored for the extent of spinal metastases, presence and severity of spinal cord compression, and nerve root compression. Two MRI-based scales were used to evaluate the degree of cord compression and spinal canal narrowing and relate these findings to neurological function.

RESULTS

Of the patients included in the study, 28 were non-ambulatory, 49 were ambulatory with minor motor deficits, and 207 had normal motor function. Spinal cord compression was present in all patients with Frankel scores of B or C, 23 of 35 patients with a Frankel score of D (66%), and 48 of 152 patients with a Frankel score of E (32%). The percentage of patients with severe spinal canal narrowing increased with increasing Frankel grades. The grading according to the scales showed a significant association with the symptoms according to the Frankel scale (P < 0.001).

CONCLUSION

In patients with neurological dysfunction, the presence and severity of impairment was associated with the epidural tumor burden. A significant number of patients had radiological spinal cord compression and normal motor function (occult MSCC).

Malignant extradural spinal cord compression in men with prostate cancer

PURPOSE OF REVIEW

Malignant epidural spinal cord compression (MESCC) is a dreaded complication of malignancy and is fortunately not common. Approximately 7% of men dying of prostate cancer will have at least one episode of MESCC during their lifetime. Treatment needs to be individualized and estimating the prognosis is critical to achieving a balance between effectiveness therapy and the burden of treatment.

RECENT FINDINGS

A consortium of multiple centers has defined prognosis scales, and multiple randomized studies have helped define the optimal dose fractionation schedule for patients getting radiotherapy.

SUMMARY

Simple prognosis scales available to assist the clinician are reviewed. For poor prognosis patients, a single fraction of 8  Gy is just as effective as multiple fractions, however, are much more convenient. For good prognosis patients, surgery and radiation should be considered. For patients not getting surgery, enrollment in clinical trials of single vs. multiple fractions of radiation should be a priority. For high-risk patients, screening strategies are being developed and hold promise for maintaining ambulation throughout the patients' lifetime.

A Systematic and Evidence-Based Approach to the Management of Vertebral Metastasis

Diagnosis and management of vertebral metastasis requires a systematic approach to patient identification as well as selection of appropriate therapy. Rapid identification and prompt intervention in the treatment of malignant epidural spinal cord compression (MESCC) is key to maintaining quality of life. This paper provides a series of tools as well as guidance in selecting effective and evidence-based therapy individualized to the specific patient.