Spinal Metastases: Impact of early surgery plus concomitant radiation compared to radiation therapy only on health-related quality of life and overall survival

Abstract Portions of this work were included in an oral presentation held at the Annual Meeting of the Neurological Surgeons in San Francisco, USA on October 16th, 2022. Objective: Spinal metastases can be associated with varying degrees of mechanical instability. The Spinal Instability Neoplastic Score (SINS) was developed to assess neoplastic-induced spinal instability. This study aimed to compare the quality of life and overall survival of patients who underwent surgical instrumentation and radiation therapy versus those who only received radiation therapy for spinal metastases. Additionally, controversy continues as to whether vertebral body replacement is mandatory. Methods: This study aimed to compare the quality of life and overall survival of patients who underwent surgical instrumentation or vertebral body replacement and radiation therapy compared to those who only received radiation therapy for spinal metastases. The study design was a matched-paired analysis according to the SINS score, gender, age, histology and Karnofsky Performance Index. We included all patients who received dorsal instrumentation with a carbon-PEEK system between January 2020 and December 2021. As a comparison group, we chose patients from 2018 who were treated conservatively. Results: 42 patients were identified in each group. The median age was 67 SD +/- 14.6 and 40% were female. The most common histology was plasmacytoma observed in 31% of cases, followed by bronchial cancer in 19%. Instable and potentially unstable fractures were observed in 76% and 24% of patients, respectively. The overall survival rate was 69% and 80% in the radiation therapy and surgery / radiation therapy groups, respectively. When analyzing quality of life, we selected walking ability as the main feature. At the follow-up time point, 100% of patients in the intervention group were able to walk, noting that 12% (n=5) were in the state of incomplete paraparesis (ASIA C) at the time of surgery. In the control group, walking ability was present in 79% of cases at the follow-up time point, with an initial ASIA score distribution of 95% ASIA E and 5% ASIA D. Conclusion: A tailored surgical approach according to the SINS score leads to longer overall survival and higher rates of preservation of walking ability in patients with spinal metastases. There is also evidence that primary 360 degree stabilization is not necessary in the oncological setting.