Correlation of the Levels of the Bone Turnover Markers BAP and β-CTX with Bone Metastasis Progress in Lung Cancer Patients

Background and objective Bone metastasis is common in lung cancer patients. The β isomer of the C-terminal telopeptide of type I collagen (β-CTX) and bone-specific alkaline phosphates (BAP) are regarded as important bone turnover markers in bone resorption and formation. Thus, the aims of this study are to determine the correlation of these bone turnover markers with the extent of bone metastasis of lung cancer. Methods A total of 92 patients with bone metastasis of lung cancer from Tianjin Union Medicine Center were enrolled in this study between July 2009 and July 2012. The bone metastasis lesion was diagnosed by ECT combined with X-ray and CT imaging. The bone turnover marker levels of β-CTX and BAP were measured by ELISA. Results Among the 92 patients, 58 cases had <3 bone-metastasis number and 34 had ≥3; 68 cases had osteolytic bone metastasis, 9 had osteoblastic bone metastasis, and 15 had mixed bone metastases. The serum levels of β-CTX and BAP were significantly higher in patients with >3 bone-metastasis number than that in patients with less than 3 (P<0.05). β-CTX was more sensitive than BAP in diagnosing lytic bone metastasis. Conclusion β-CTX and BAP can be used as supplementary tools for diagnosing and screening bone metastasis of lung cancer.