Comparison of Bone Scintigraphy with Bone Markers in the Diagnosis of Bone Metastasis in Lung Carcinoma Patients

This study was designed to evaluate the utility of the bone markers total alkaline phosphatase (TAP), bone-specific alkaline phosphatase (BAP), aminoterminal propeptide of type I collagen (PINP), carboxyterminal propeptide of type I collagen (PICP), pyridinoline crosslinks (PYD), deoxypyridinoline crosslinks (DPD), cross-linked carboxyterminal telopeptide of type I collagen (ICTP), cross-linked carboxyterminal telopeptide of type I collagen (CTx, β-CrossLaps) and tartrate-resistant acid phosphatase 5b (TRAP 5b) in comparison with bone scintigraphy for the diagnosis of bone metastasis in lung carcinoma patients. The study population consisted of 49 patients with bone metastasis confirmed by plain radiography and/or computed tomography, 89 patients without bone metastasis, 12 patients with benign lung diseases and 18 healthy persons. All patients were of male gender. The bone markers were measured using commercially available tests. Serum and urine were collected from fasting patients at the time of bone scan between 7.00 and 8.00 a.m. The sensitivity of bone scintigraphy was 100%, its specificity 76.4%, resulting in a diagnostic efficiency of 84.8%. The positive predictive value was calculated to be 70% and the negative one to be 100%. The concentrations of the bone markers TAP, BAP, PINP, PYD, DPD and ICTP were significantly higher in patients with bone metastasis than in those without bone metastasis (p