Antar, Albert

OBJECTIVE Intramedullary spinal cord tumors (IMSCTs) are typically treated with maximal safe resection, during which neurosurgeons often monitor for neurological injury using muscle motor evoked potential (mMEP) and direct wave (D-wave) neuromonitoring. The predictive value of changes in D-waves for identifying motor outcomes is underexplored. This study evaluated the utility of D-waves for predicting postoperative motor deficits. METHODS Patients who underwent resection of a primary IMSCT with mMEP neuromonitoring from 2003 to 2023 at a tertiary care hospital were identified. Patients who underwent D-wave monitoring in addition to mMEP monitoring were compared to those who underwent mMEP monitoring alone using the Mann-Whitney U-test, chi-square test, and Fisher’s exact test. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of D-wave and mMEP monitoring for identifying new neurological deficits immediately postoperatively and at 1 month, 6 months, and last follow-up were calculated. RESULTS After matching, 125 patients were included (median age 42.0 years; 57.6% male; median follow-up 34.0 months), of whom 88 had both mMEP and D-wave data. The most common pathologies were ependymoma (64.0%) and astrocytoma (17.6%). Patients who did and did not undergo D-wave neuromonitoring had similar preoperative neurological function, primary pathology, tumor grade, and tumor location. D-wave use was associated with increased gross-total resection (88.6% vs 64.9%, p = 0.002) and reduced mortality (5.7% vs 24.3%, p = 0.007), length of stay (5.0 vs 6.0 days, p = 0.033), and 30-day readmission (2.3% vs 13.5%, p = 0.013) and reoperation (1.1% vs 10.8%, p = 0.012). At the 6-month follow-up, D-wave monitoring alone was superior to mMEP and combination monitoring for detecting new motor deficits. D-wave monitoring had peak sensitivity (77.8%) and NPV (96.5%) at 6 months and peak specificity (95.8%) and PPV (76.9%) in the immediate postoperative period. CONCLUSIONS D-wave monitoring was associated with reduced mortality and was more accurate than mMEP monitoring alone or combination monitoring for detecting new postoperative neurological deficits. Further prospective studies are needed to validate these results.

OBJECTIVE Intramedullary spinal cord tumors (IMSCTs) are rare neoplasms whose treatment is often technically challenging. Given the low volume seen at most centers, perioperative outcomes have been reported infrequently. Here, the authors present the largest single-institution series of IMSCTs, focusing on the clinical presentation, histological makeup, perioperative outcomes, and long-term survival of surgically treated patients. METHODS A cohort of patients operated on for primary IMSCTs at a comprehensive cancer center between June 2002 and May 2020 was retrospectively identified. Data on patient demographics, tumor histology, neuraxial location, baseline neurological status, functional deficits, and operative characteristics were collected. Perioperative outcomes of interest included length of stay, postoperative complications, readmission, reoperation, and discharge disposition. Data were compared across tumor histologies using the Kruskal-Wallis H test, chi-square test, and Fisher exact test. Pairwise comparisons were conducted using Tukey’s honest significant difference test, chi-square test, and Fisher exact test. Long-term survival was assessed across tumor categories and histological subtype using the log-rank test. RESULTS Three hundred two patients were included in the study (mean age 34.9 ± 19 years, 77% white, 57% male). The most common tumors were ependymomas (47%), astrocytomas (31%), and hemangioblastomas (11%). Ependymomas and hemangioblastomas disproportionately localized to the cervical cord (54% and 59%, respectively), whereas astrocytomas were distributed almost equally between the cervical cord (36%) and thoracic cord (38%). Clinical presentation, extent of functional dependence, and postoperative 30-day outcomes were largely independent of underlying tumor pathology, although tumors of the thoracic cord had worse American Spinal Injury Association (ASIA) grades than cervical tumors. Rates of gross-total resection were lower for astrocytomas than for ependymomas (54% vs 84%, p < 0.01) and hemangioblastomas (54% vs 100%, p < 0.01). Additionally, 30-day readmission rates were significantly higher for astrocytomas than ependymomas (14% vs 6%, p = 0.02). Overall survival was significantly affected by the underlying pathology, with astrocytomas having poorer associated prognoses (40% at 15 years) than ependymomas (81%) and hemangioblastomas (66%; p < 0.01) and patients with high-grade ependymomas and astrocytomas having poorer long-term survival than those with low-grade lesions (p < 0.01). CONCLUSIONS The neuraxial location of IMSCTs, extent of resection, and postoperative survival differed significantly across tumor pathologies. However, perioperative outcomes did not vary significantly across tumor cohorts, suggesting that operative details, rather than pathology, may have a stronger influence on the short-term clinical course, whereas pathology appears to have a stronger impact on long-term survival.

OBJECTIVE Previous studies have suggested the possibility of racial disparities in surgical outcomes for patients undergoing spine surgery, although this has not been thoroughly investigated in those with spinal metastases. Given the increasing prevalence of spinal metastases requiring intervention, knowledge about potential discrepancies in outcomes would benefit overall patient care. The objective in the present study was to investigate whether race was an independent predictor of postoperative complications, nonroutine discharge, and prolonged length of stay (LOS) after surgery for spinal metastasis. METHODS The authors retrospectively examined patients at a single comprehensive cancer center who had undergone surgery for spinal metastasis between April 2013 and April 2020. Demographic information, primary pathology, preoperative clinical characteristics, and operative outcomes were collected. Factors achieving p values < 0.15 on univariate regression were entered into a stepwise multivariable logistic regression to generate predictive models. Nonroutine discharge was defined as a nonhome discharge destination and prolonged LOS was defined as LOS greater than the 75th percentile for the entire cohort. RESULTS Three hundred twenty-eight patients who had undergone 348 operations were included: 240 (69.0%) White and 108 (31.0%) Black. On univariable analysis, cohorts significantly differed in age (p = 0.02), marital status (p < 0.001), insurance status (p = 0.03), income quartile (p = 0.02), primary tumor type (p = 0.04), and preoperative Karnofsky Performance Scale (KPS) score (p < 0.001). On multivariable analysis, race was an independent predictor for nonroutine discharge: Black patients had significantly higher odds of nonroutine discharge than White patients (adjusted odds ratio [AOR] 2.24, 95% confidence interval [CI] 1.28–3.92, p = 0.005). Older age (AOR 1.06 per year, 95% CI 1.03–1.09, p < 0.001), preoperative KPS score ≤ 70 (AOR 3.30, 95% CI 1.93–5.65, p < 0.001), preoperative Frankel grade A–C (AOR 3.48, 95% CI 1.17–10.3, p = 0.02), insurance status (p = 0.005), being unmarried (AOR 0.58, 95% CI 0.35–0.97, p = 0.04), number of levels (AOR 1.17 per level, 95% CI 1.05–1.31, p = 0.004), and thoracic involvement (AOR 1.71, 95% CI 1.02–2.88, p = 0.04) were also predictive of nonroutine discharge. However, race was not independently predictive of postoperative complications or prolonged LOS. Higher Charlson Comorbidity Index (AOR 1.22 per point, 95% CI 1.04–1.43, p = 0.01), low preoperative KPS score (AOR 1.84, 95% CI 1.16–2.92, p = 0.01), and number of levels (AOR 1.15 per level, 95% CI 1.05–1.27, p = 0.004) were predictive of complications, while insurance status (p = 0.05), income quartile (p = 0.01), low preoperative KPS score (AOR 1.64, 95% CI 1.03–2.72, p = 0.05), and number of levels (AOR 1.16 per level, 95% CI 1.05–1.30, p = 0.004) were predictive of prolonged LOS. CONCLUSIONS Race, insurance status, age, baseline functional status, and marital status were all independently associated with nonroutine discharge. This suggests that a combination of socioeconomic factors and functional status, rather than medical comorbidities, may best predict postdischarge disposition in patients treated for spinal metastases. Further investigation in a prospective cohort is merited.