Utilization of inpatient radiation therapy and spine surgery during hospitalization for metastatic spinal cord compression

Abstract

Purpose/Objective(s) Patients with spinal metastases are at risk for malignant spinal cord compression (MSCC), warranting urgent intervention. Early intervention using radiation therapy (RT) and spinal surgery can improve outcomes for these patients. Data regarding inpatient management of MSCC and subtypes of interventions are lacking. We assessed utilization of RT or spinal surgery as measures of quality of care during hospitalizations for patients with MSCC. Materials/Methods We analyzed all hospitalizations of patients ≥18 years with a primary diagnosis of metastatic cancer with bone metastases and spinal cord compression from the National Inpatient Sample (covering 97% of the U.S. population) from 2010-2020. We used χ2 tests to assess associations between receipt of RT/surgery, discharge outcome, and early versus late intervention. Results Among 11,764 hospitalizations for MSCC, 61.3% received inpatient RT (of which 1.2% was stereotactic body radiotherapy) or spinal surgery. 4.1% of those that received an intervention utilized both surgery and RT; 33.3% received RT only, 62.6% received surgery only. In-patients who received both RT and surgery had a longer hospitalization (median 17 days, IQR 11-26) than those that received only one intervention (median 8 days, IQR 6-13) and those that received neither intervention (median 5 days, IQR 3-10). Time from admission to surgery alone (median 1 day, IQR 0-3) was shorter than time to RT alone (median 2 days, IQR 1-4). Inpatients that received RT or surgery were less likely to be rapidly declining compared to those that received neither intervention (4.0% died during admission versus 6.0%, P< 0.001), and less likely to be transferred to short-term hospitals (2.1% versus 9.5%, P< 0.001). Hospital characteristics associated with increased likelihood of receiving RT or surgery were large hospitals, non-profit, and urban institutions. Among inpatients that received RT/surgery, late utilization of these interventions (after the first two days of hospitalization) was associated with a higher likelihood of death during admission compared to earlier intervention (4.9% versus 3.6%, P = 0.009). There was no significant difference in the discharge locations (home, skilled nursing facility, or hospital transfer) between inpatients with earlier versus later intervention. Conclusion Inpatient RT or surgery are utilized for most patients hospitalized for MSCC and are associated with a lower likelihood of poor discharge outcomes. While we are limited in determining underlying reasons for triage to RT, surgery, both, or no intervention, our results suggest the current triage system appropriately differentiates patients based on differences in survival. Delays to intervention, however, are associated with an increased likelihood of death during admission. Our findings support further investigation of indications for inpatient post-operative RT and the relationship between delays in inpatient RT planning and outcomes for patients hospitalized with MSCC.