Surgical Resection of Dorsal Spinal Meningiomas with the Inner Dura Layer - an Improved Preservation Technique of Spinal Dura in 40 Cases

Spinal Meningiomas: A Comprehensive Review and Update on Advancements in Molecular Characterization, Diagnostics, Surgical Approach and Technology, and Alternative Therapies

Spinal meningiomas are the most common intradural, extramedullary tumor in adults, yet the least common entity when accounting for all meningiomas spanning the neuraxis. While traditionally considered a benign recapitulation of their intracranial counterpart, a paucity of knowledge exists regarding the differences between meningiomas arising from these two anatomic compartments in terms of histopathologic subtypes, molecular tumor biology, surgical principles, long-term functional outcomes, and recurrence rates. To date, advancements at the bench have largely been made for intracranial meningiomas, including the discovery of novel gene targets, DNA methylation profiles, integrated diagnoses, and alternative systemic therapies, with few exceptions reserved for spinal pathology. Likewise, evolving clinical research offers significant updates to our understanding of guiding surgical principles, intraoperative technology, and perioperative patient management for intracranial meningiomas. Nonetheless, spinal meningiomas are predominantly relegated to studies considering non-specific intradural extramedullary spinal tumors of all histopathologic types. The aim of this review is to comprehensively report updates in both basic science and clinical research regarding intraspinal meningiomas and to provide illustrative case examples thereof, thereby lending a better understanding of this heterogenous class of central nervous system tumors.

Association of quantitative radiomic shape features with functional outcome after surgery for primary sporadic dorsal spinal meningiomas

Objective

Spinal meningiomas (SM) account for 25%-46% of all primary spinal tumors and show an excellent long-term disease control in case of complete resection. Therefore, the postoperative functional outcome is of high importance. To date, reports on dorsally located SM are scarce. Moreover, the impact of radiomics shape features on the functional outcome after surgery for primary dorsal SMs has not been analyzed yet.

Methods

We retrospectively performed an analysis of shape-based radiomic features in 3D slicer software and quantified the tumor volume, surface area, sphericity, surface area to volume ratio and tumor canal ratio. Subsequently, we evaluated the correlation between the radinomic parameters and the postoperative outcome according to Modified Japanese Orthopedic Association (mJOA) score.

Results

Between 2010 and 2022, we identified 24 Females and 2 Males operated on dorsal SMs in our institutional database. The most common SM localization was thoracic spine (n = 20), followed by cervical (n = 4), and lumbar (n = 2). The univariate analysis and the receiver operating characteristic (ROC) analysis showed a strong diagnostic performance of sphericity in the prediction of postoperative functional outcome based on mJOA score (AUC of 0.79, sphericity cut-of value 0.738; p = 0.01). Subsequently, the patients were divided into two groups (mJOA improved vs. mJOA stable/worsened). Patients with improved mJOA score showed significantly higher sphericity (0.79 ± 0.1 vs. 0.70 ± 1.0; p = 0.03). Finally, we divided the cohort based on sphericity (<0.738 and ≥0.738). The group with higher sphericity exhibited a significantly higher positive mJOA difference 3 months postoperatively (16.6 ± 1.4 vs. 14.8 ± 3.7; p = 0.03).

Conclusion

In our study investigating primary sporadic dorsal SMs, we demonstrated that a higher degree of sphericity may be a positive predictor of postoperative improvement, as indicated by the mJOA score.

Quality of Life and Postoperative Satisfaction in Patients with Benign Extramedullary Spinal Tumors: A Multicenter Study

STUDY DESIGN

Retrospective cohort study using prospectively collected registry data.

OBJECTIVE

The purpose of this study is to evaluate health-related quality of life (HRQOL) and postoperative satisfaction in patients with different histotypes of benign extramedullary spinal tumors (ESTs).

BACKGROUND

Little is known about how different histotypes influence HRQOL and postoperative satisfaction in EST patients.

MATERIALS AND METHODS

Patients undergoing primary benign EST surgery at 11 tertiary referral hospitals between 2017 and 2021 who completed preoperative and 1-year postoperative questionnaires were included. HRQOL assessment included the Physical Component Summary and Mental Component Summary (MCS) of Short Form-12, EuroQol 5-dimension, Oswestry/Neck Disability Index (ODI/NDI), and Numeric Rating Scales (NRS) for upper/lower extremities (UEP/LEP) and back pain (BP). Patients who answered "very satisfied," "satisfied," or "somewhat satisfied" on a seven-point Likert scale were considered to be satisfied with treatment. Student t -tests or Welch's t -test were used to compare continuous variables between two groups, and one-way analysis of variance was used to compare outcomes between the three groups of EST histotypes (schwannoma, meningioma, atypical). Categorical variables were compared using the χ 2 test or Fisher exact test.

RESULTS

A total of 140 consecutive EST patients were evaluated; 100 (72%) had schwannomas, 30 (21%) had meningiomas, and 10 (7%) had other ESTs. Baseline Physical Component Summary was significantly worse in patients with meningiomas ( P =0.04), and baseline NRS-LEP was significantly worse in patients with schwannomas ( P =0.03). However, there were no significant differences in overall postoperative HRQOL or patient satisfaction between histology types. Overall, 121 (86%) patients were satisfied with surgery. In a subgroup analysis comparing intradural schwannomas and meningiomas adjusted for patient demographics and tumor location with inverse probability weighting, schwannoma patients had worse baseline MCS ( P =0.03), ODI ( P =0.03), NRS-BP ( P <.001), and NRS-LEP ( P =0.001). Schwannoma patients also had worse postoperative MCS ( P =0.03) and NRS-BP ( P =0.001), with no significant difference in the percentage of satisfied patients ( P =0.30).

CONCLUSIONS

Patients who underwent primary benign EST resection had a significant improvement in HRQOL postoperatively, and ~90% of these patients reported being satisfied with their treatment outcomes one year after surgery. EST patients may exhibit a relatively lower threshold for postoperative satisfaction compared with patients undergoing surgery for degenerative spine conditions.

Indications for Fusion With Intradural Spine Tumor Resection in Adults: A Systematic Review and Meta-analysis

BACKGROUND

The evidence for instrumented fusion in the setting of degenerative, traumatic, or congenital deformity is well established. Data on fusion indications in intradural spinal tumors (IDST) are scarce and reduced to retrospective studies. The objective of this work is to systematically review the published literature since 2015 and analyze the change of practice patterns for stabilization and fusion after intradural tumor resection in adults.

METHODS

A systematic literature review was performed via PubMed with the terms: "intradural spinal tumors", "intramedullary spinal tumors", and "intraspinal tumors". The analysis was limited to adult patients with IDST and studies with more than 10 patients. Data on the proportion of patients who underwent instrumentation and had postoperative deformity was pooled in a meta-analysis.

RESULTS

A total of 1073 articles were identified and 47 papers were selected. All the studies were retrospective series and a total of 2473 patients were included. The follow-up ranged from 1 to 96 months, the pooled spinal fixation rate was 6% (95% CI 4.5%-7.6%), the pooled laminoplasty rate was 14.4% (95% CI 5.9%-23%), the pooled rate of postoperative deformity or malalignment in patients with a follow up of at least 6 months was 2.1% (95% CI 1.2%-3%) and just 7 patients were reoperated due to progressive deformity.

CONCLUSIONS

Based on existing evidence, the rate of fusion during resection of intradural spinal tumors is low. Prophylactic fixation is often unnecessary and only indicated in unique cases that require extensive bony resection.

Primary Benign Tumors of the Spinal Canal

Benign tumors that grow in the spinal canal are heterogeneous neoplasms with low incidence; from these, meningiomas and nerve sheath tumors (neurofibromas and schwannomas) account for 60%-70% of all primary spinal tumors. Benign spinal canal tumors provoke nonspecific clinical manifestations, mostly related to the affected level of the spinal cord. These tumors present a challenge for the patient and healthcare professionals, for they are often difficult to diagnose and the high frequency of posttreatment complications. In this review, we describe the epidemiology, risk factors, clinical features, diagnosis, histopathology, molecular biology, and treatment of extramedullary benign meningiomas, osteoid osteomas, osteoblastomas, aneurysmal bone cysts, osteochondromas, neurofibromas, giant cell tumors of the bone, eosinophilic granulomas, hemangiomas, lipomas, and schwannomas located in the spine, as well as possible future targets that could lead to an improvement in their management.