Current trends in incidence, characteristics, and surgical management of metastatic breast cancer to the spine: A National Inpatient Sample analysis from 2005 to 2014

Abstract

Management of metastatic breast cancer to the spine (MBCS) incorporates a multimodal approach. Improvement in screening and nonsurgical therapies may alter the trends in surgical management of MBCS. The objective of this study is to assess trends in surgical management of MBCS and short-term outcomes based on the National Inpatient Sample (NIS) database. The NIS database was queried for patients with MBCS who underwent surgery from 2005 to 2014. The weighted frequencies of spinal decompression alone, spinal stabilization +/- decompression, and vertebral augmentation were calculated. Multivariate analysis was performed to analyze the effect of patient characteristics on outcomes stratified by procedure. The most common procedure performed was vertebral augmentation (11,114, 53.4%), followed by stabilization +/− decompression (6,906, 33.2%) and then decompression alone (3,312, 13.4%). The total population-adjusted rate of surgical management for MBCS remained stable, while the rate of spinal stabilization increased (P < 0.001) and vertebral augmentation decreased (p < 0.003). The risk of complication increased with spinal stabilization and decompression compared to vertebral augmentation procedures in those with fewer comorbidities. This relative increase in risk abated in patients with higher numbers of pre-operative comorbidities. Any single complication was associated with increases in length of stay, cost, and mortality. The rate of in-hospital interventions remained stable over the study period. Stratified by procedure, the rate of stabilizations increased with a concomitant decrease in vertebral augmentations, which suggests that patients who require hospitalization for MBCS are becoming more likely to represent advanced cases that are not amenable to palliative vertebral augmentation procedures.