Prevalence of Spinal Metastasis in Neurosurgical Procedures: A Descriptive Study

Objective: This study sought to identify the prevalence of operations for spinal epidural neoplastic metastases relative to other spine and neurosurgical operative procedures. Methods: This study was descriptive and involved a retrospective review of data collected from patients who underwent neurosurgeries between February 1997 and January 2015 at a single quaternary hospital. The examined population was distributed across five descriptive categories to perform numerical distributions among neurosurgical operative procedures. Results: A total of 12,802 neurosurgical procedures were identified. These procedures were classified as follows: Skull and brain, 11,192 (87.42%); spinal column and spinal nervous tissue, 1462 (11.42%); and peripheral nerves, 148 (1.16%). Surgical procedures for the 1462 (100%) cases of spinal column and spinal nervous tissue diseases were distributed by nosology as follows: Degenerative intervertebral disk and spondylosis, 768 (52.54%); neoplastic, 279 (19.08%); traumatic, 221 (15.11%); congenital, 163 (11.14%); infectious and inflammatory, 27 (1.85%); and vascular, 4 (0.28%). With respect to the distribution of the 279 (100%) surgical procedures for spinal column and spinal nervous tissue neoplastic diseases, 124 (44.44%) procedures were for intradural neoplasms, and 155 (55.56%) procedures were for epidural spinal column neoplasms. The 155 (100%) operations for epidural neoplastic diseases were distributed into two groups: Primary epidural neoplasms, 42 (27.10%); and secondary epidural neoplasms, 113 (72.90%). Spinal column epidural neoplastic metastases (secondary neoplasms) represented 0.88% of the 12,802 neurosurgical procedures. Conclusions: Surgical procedures for spinal metastasis are uncommon with respect to all neurosurgical operative procedures. Trend analysis reveals an unchanging trend of prevalence for these procedures.