Factors Affecting Survival in Patients Undergoing Palliative Spine Surgery for Metastatic Lung and Hepatocellular Cancer: Dose the Type of Surgery Influence the Surgical Results for Metastatic Spine Disease?

BACKGROUND: Surgical treatment for metastatic spine disease has been becoming more prominent with the help of technological advances and a few favorable reports on the surgery. In cases of this peculiar condition, it is necessary to establish the role of surgery and analyze the factors affecting survival. METHODS: From January 2011 to April 2015, 119 patients were surgically treated for metastatic spine lesions. To reduce the bias along the heterogeneous cancers, the primary cancer was confined to either the lung (n = 25) or the liver (n = 18). Forty-three patients (male, 32; female, 11; mean age, 57.5 years) who had undergone palliative surgery were enrolled in this study. Posterior decompression and fusion was performed in 30 patients (P group), and anteroposterior (AP) reconstruction was performed in 13 patients (AP group) for palliative surgery. Pre- and postoperative (3 months) pain (visual analogue scale, VAS), performance status (Karnofsky performance score), neurologic status (American Spinal Injury Association [ASIA] grade), and spinal instability neoplastic score (SINS) were compared. The survival period and related hazard factors were also assessed by Kaplan-Meier and Cox regression analysis. RESULTS: Most patients experienced improvements in pain and performance status (12.3% ± 17.2%) at 3 months postoperatively. In terms of neurologic recovery, 9 patients (20.9%) graded ASIA D experienced neurological improvement to ASIA E while the remainder was status quo. In an analysis according to operation type, there was no significant difference in patient demographics. At 12 months postoperatively, cumulative survival rates were 31.5% and 38.7% for the P group and the AP group, respectively (p > 0.05). Survival was not affected by the pre- and postoperative pain scale, Tokuhashi score, neurologic status, SINS, or operation type. Preoperative Karnofsky performance score (hazard ratio, 0.93; 95% confidence interval [CI], 0.89 to 0.96) and improvement of performance status after surgery (hazard ratio, 0.95; 95% CI, 0.92 to 0.97) significantly affected survival after operation. CONCLUSIONS: There was no significant difference in surgical outcomes and survival rates between posterior and AP surgery for metastatic lesions resulting from lung and hepatocellular cancer. Preoperative Karnofsky score and improvement of performance status had a significant impact on the survival rate following surgical treatment for these metastatic spine lesions.