Clinical, surgical, and molecular prognostic factors for survival after spinal sarcoma resection.

OBJECTIVE The goal of this study was to investigate the local recurrence rate and long-term survival after resection of spinal sarcomas. METHODS A retrospective review of patients who underwent resection of primary or metastatic spinal sarcomas between 1997 and 2015 was performed. Tumors were classified according to the Enneking classification, and resection was categorized as Enneking appropriate (EA) if the specimen margins matched the Enneking recommendation, and as Enneking inappropriate (EI) if they did not match the recommendation. The primary outcome measure for all tumors was overall survival; local recurrence was also an outcome measure for primary sarcomas. The association between clinical, surgical, and molecular (tumor biomarker) factors and outcomes was also investigated. RESULTS A total of 60 patients with spinal sarcoma were included in this study (28 men and 32 women; median age 38 years). There were 52 primary (86.7%) and 8 metastatic sarcomas (13.3%). Thirty-nine tumors (65.0%) were classified as high-grade, and resection was considered EA in 61.7% of all cases (n = 37). The local recurrence rate was 10 of 52 (19.2%) for primary sarcomas; 36.8% for EI resection and 9.1% for EA resection (p = 0.010). Twenty-eight patients (46.7%) died during the follow-up period, and median survival was 26 months. Overall median survival was longer for patients with EA resection (undefined) compared with EI resection (13 months, p < 0.001). After multivariate analysis, EA resection significantly decreased the hazard of local recurrence (HR 0.24, 95% CI 0.06-0.93; p = 0.039). Age 40 years or older (HR 4.23, 95% CI 1.73-10.31; p = 0.002), previous radiation (HR 3.44, 95% CI 1.37-8.63; p = 0.008), and high-grade sarcomas (HR 3.17, 95% CI 1.09-9.23; p = 0.034) were associated with a significantly increased hazard of death, whereas EA resection was associated with a significantly decreased hazard of death (HR 0.22, 95% CI 0.09-0.52; p = 0.001). CONCLUSIONS The findings in the present study suggest that EA resection may be the strongest independent prognostic factor for improved survival in patients with spinal sarcoma. Additionally, patients who underwent EA resection had lower local recurrence rates. Patients 40 years or older, those with a history of previous radiation, and those with high-grade tumors had an increased hazard of mortality in this study.