2800 - The Inpatient Metastatic Spine Score: Prospective Validation on a Phase Two Randomized Controlled Trial

Purpose/Objective(s):

Patients with exceedingly poor prognoses from spinal metastatic disease may not benefit from the durable local control advantages of stereotactic body radiation therapy (SBRT) over conventional external beam radiation therapy (EBRT), which optimally manifest at 6-12 months post-treatment. The Inpatient Metastatic Spine Score has been demonstrated to accurately assess prognosis in this patient population (PMID 40025847). Due to the low historical accuracy rate (25%) of Medical Oncology prognosis for this patient population (PMID 38992872), this study examines the accuracy of the Inpatient Metastatic Spine Score for inpatients prospectively considered for enrollment on the Spine Patient Optimal Radiosurgery Treatment for Symptomatic MEtastatic Neoplasms (SPORTSMEN) multicenter Phase II randomized controlled trial.

Materials/Methods:

From 5/2025-2/2026, inpatients at a National Cancer Institute-designated cancer center were prospectively considered for SPORTSMEN inclusion. Prognosis was assessed per the Inpatient Metastatic Spine Score consisting of: age at admission (60+ vs younger), duration of metastatic disease diagnosis (6+ months vs sooner), on active systemic therapy/refractory to systemic therapy (yes/no), additional non-spine metastatic focus (yes/no), severe malnutrition of chronic disease (yes/no), brain metastases (yes/no), and admission for symptomatology besides spine/back pain (yes/no) with each category scored as a 0 (no) or 1 (yes) and a cumulative score derived for each patient. Patients with scores of 0-3 were recommended for SBRT (and potential SPORTSMEN enrollment) due to a predicted positive prognosis (3+ months before death/hospice). Patients with scores 4-7 were deemed SPORTSMEN-ineligible and recommended for EBRT or no radiation therapy due to predicted negative prognosis (<3 months before death/hospice). Scores and recommendations were correlated with actual patient prognosis. Fisher’s test was used for statistical analysis.

Results:

A total of 25 inpatients were evaluated. 7/11 (64%) with scores from 0-3 had positive prognosis, while 3/14 (21%) with scores from 4-7 had positive prognosis; this difference was statistically significant (p=0.0486). The accuracy of the Inpatient Metastatic Spine Score (7/11 positive + 11/14 negative = 18/25 patients = 72%) was significantly greater than the historical rate of Medical Oncology prognosis (p=0.0351).

Conclusion:

The accuracy of the Inpatient Metastatic Spine Score for prospectively assessing the prognosis of inpatients with spine metastases for a randomized controlled trial was 72%, significantly superior to that historically provided by Medical Oncology prognosis. These findings strongly support that the prognosis of inpatients with spinal metastases is most accurately determined by the Inpatient Metastatic Spine Score, and that this heuristic algorithm should be viewed as the standard-of-care for accurately evaluating prognosis in this patient population.