Survival Analysis of and Prognostic Factors for Metastatic Epidural Spinal Cord Compression Compared between Preoperative Known and Unknown Primary Tumors

Abstract

Objective: To analyze the median survival time of and prognostic factors for metastatic epidural spinal cord compression (MESCC) secondary to preoperative unknown primary tumor (pre-op UPT) compared to MESCC secondary to preoperative known primary tumor (pre-op KPT). Materials and Methods: This retrospective cohort study reviewed all consecutive MESCC patients who underwent surgical decompression with or without stabilization within 72 hours of admission during 2010 to 2016. Survival was compared between the pre-op UPT and pre-op KPT groups, and preoperative and postoperative prognostic factors for survival were analyzed. Results: A total of 169 patients (pre-op UPT: 51, and pre-op KPT: 118) were enrolled. The survival rate at 3, 6, and 12 months was 84.3%, 58.8%, and 47.1% in the pre-op UPT group, and 72.0%, 48.3%, and 34.7% in the pre-op KPT group, respectively. The median survival time secondary to lung cancer was significantly longer in the pre-op UPT group (6.0±1.4 months) than in the pre-op KPT group (3.6±0.2 months) (p=0.031). Multivariate analysis revealed survival time to be influenced by preoperative known or unknown primary tumor status, revised Tokuhashi score, the adjuvant therapy, and postoperative complications, including myocardial infarction, gastrointestinal bleeding, and urinary tract infection. Conclusion: MESCC secondary to preoperative unknown primary tumor patients who had the clinical presentation with acute progressive neurological deficits who need urgency spine surgery has comparable survival to MESCC secondary to preoperative known primary tumors.