2020 Volume 11 Issue 5 Pages 848-852
Introduction: Diagnostic tumor markers for identifying spinal metastases of unknown origin (SMUO) at initial presentation are unknown. Therefore, we aimed to determine the predictive ability of 17 tumor markers for identifying primary sites of spinal metastases.
Methods: We recruited 240 patients with SMUO at the Komagome Hospital between January 2007 and August 2018. The patients had primary pathologies of the lung (n = 60), prostate (n = 34), breast (n = 15), thyroid (n = 11), pancreatic and bile duct (n = 11), stomach and colon (n = 13), and other digestive organs (n = 33) and all named cancers (n = 184), as well as multiple myeloma (n = 28), malignant lymphoma (n = 18), and others (n = 10). Diagnostic values were statistically determined as areas under the receiver operating characteristics curve (AUCs).
Results: Significant tumor markers determined using AUCs comprised thyroglobulin (Tg) for thyroid cancer (AUC = 1.0), prostate-specific antigen (PSA) for prostate cancer (AUC = 0.94), carbohydrate antigen 19-9 (CA19-9) and pancreatic cancer-associated antigen for pancreatic and bile duct cancer (AUC = 0.89 and 0.83, respectively), sialyl SSEA-1 antigen (SLX) for lung cancer (AUC = 0.81), CA19-9 for digestive cancer (AUC = 0.74), carbohydrate antigen 153 (CA153) for breast cancer (AUC = 0.73), carcinoembryonic antigen (CEA) for stomach and colon cancer (AUC = 0.73), soluble interleukin 2 receptor (sIL-2R) for malignant lymphoma (AUC = 0.73), and tissue polypeptide antigen/CEA for all named cancers (AUC = 0.72). Serum and urinary values determined using immunoelectrophoresis (IEP) to diagnose multiple myeloma were statistically significant (P < 0.0001, two-tailed test). On the other hand, analysis using sIL-2R is expensive, and CA153 can be substituted by inspection, palpation, and contrast-enhanced computed tomography for detecting breast cancer.
Conclusions: We recommend analyses using Tg, PSA, CA19-9, SLX, and CEA and IEP to cost-effectively identify primary sites of spinal metastases.
