Effect of Bone Metastasis Cancer Board on Spinal Surgery Outcomes: A Retrospective Study

Background and Objectives: Bone metastasis cancer boards (BMCBs) focusing on the management of bone metastases have been gathering much attention. However, the association of BMCBs with spinal surgery in patients with spinal metastases remains unclear. In this retrospective single-center observational study, we aimed to clarify the effect of a BMCB on spinal metastasis treatment. Materials and Methods: We reviewed consecutive cases of posterior decompression and/or instrumentation surgery for metastatic spinal tumors from 2008 to 2019. The BMCB involved a team of specialists in orthopedics, rehabilitation medicine, radiation oncology, radiology, palliative supportive care, oncology, and hematology. We compared demographics, eastern cooperative oncology group performance status (ECOGPS), Barthel index (BI), number of overall versus emergency surgeries, and primary tumors between patients before (2008-2012) and after (2013-2019) BMCB establishment. Results: A total of 226 patients including 33 patients before BMCB started were enrolled; lung cancer was the most common primary tumor. After BMCB establishment, the mean patient age was 5 years older (p = 0.028), the mean operating time was 34 min shorter (p = 0.025), the mean hospital stay was 34.5 days shorter (p < 0.001), and the mean BI before surgery was 12 points higher (p = 0.049) than before. Moreover, the mean number of surgeries per year increased more than fourfold to 27.6 per year (p < 0.01) and emergency surgery rates decreased from 48.5% to 29.0% (p = 0.041). Patients with an unknown primary tumor before surgery decreased from 24.2% to 9.3% (p = 0.033). Postoperative deterioration rates from 1 to 6 months after surgery of ECOGPS and BI after BMCB started were lower than before (p = 0.045 and p = 0.027, respectively). Conclusion: The BMCB decreased the emergency surgery and unknown primary tumor rate despite an increase in the overall number of spinal surgeries. The BMCB also contributed to shorter operation times, shorter hospital stays, and lower postoperative deterioration rates of ECOGPS and BI.