Epidemiological Characteristics of 1196 Patients with Spinal Metastases: A Retrospective Study.

Objectives: To describe the epidemiological characteristics of patients with spinal metastases between 2007 and 2019.
Methods: Patients with spinal metastases were identified from several clinical centers in China between January 2007 and July 2019. Demographics, primary tumor types, spinal involvement, and Clinical indicators of each patient were reviewed.
Results: A total of 1196 patients were included in this study, 717 males (59.95%) and 479 females (40.05%), with a male to female ratio of 1.50:1. Most patients (63.71%) were in the ages range of 50 to 69 years. The mean age was 58.6 ± 11.6 (range 13-89) years and the median age was 59.0 years. The average age of females was younger than that of males, and the difference was statistically significant. The proportion of male patients over 60 years old was higher than that of females, and the difference was statistically significant. The most common primary tumor was lung cancer (n = 437, 36.54%), followed by unknown origin (n = 194, 16.22%), kidney cancer (n = 78, 6.52%), breast cancer (n = 76, 6.35%), and liver/biliary cancer (n = 75, 6.27%). The most common primary tumor was lung cancer in both males and females, followed by unknown origin in males and breast cancer in females. There were 730 patients (61.04%) in the subgroup of the number<3; the highest level was lumbar vertebrae, with 250 patients (34.25%). The remaining 466 patients (38.96%) were included in the subgroup of the number ≥ 3; the highest level was tumor metastasis of multiple-level of spine, with 334 patients (71.67%). Among the 1196 patients, spinal cord injury occurred in 54.01% of patients, 76.34% of patients developed moderate and above pain, 55.69% of patients had metastatic spinal cord compression, and only 26.67% of patients had a clear history of primary tumors.
Conclusion: This study provided a relatively detailed description of epidemiological characteristics in spinal metastases in China, which could assist orthopaedic surgeons to understand the clinical characteristics of spinal metastases, and is of great significance in guiding clinical diagnoses and scientific research.
(© 2019 The Authors. Orthopaedic Surgery published by Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.)