[Diagnosis of skeletal metastases by serum tumor markers]

Levels of serum tumor markers including CEA, AFP, CA 15-3, CA 19-9, CA 125 and TPA were measured in 26 patients with bone metastases and in 9 patients with primary bone tumors. TPA was the most sensitive marker to detect skeletal metastasis being elevated in 15 of the 22 patients (68.2%). High sensitivity was observed in CEA (46.1%), CA 15-3 (40%), and CA 125 (35%), and AFP showed relatively low sensitivity (4.3%). When elevation of TPA only or elevation of more than two tumor markers including TPA was used as a screening test for skeletal metastasis, over-all sensitivity, specificity, and accuracy were 73.1%, 88.9%, and 81% respectively. No definite correlation between the markers could be seen in this study. A combination of serum tumor markers was useful in the differential diagnosis of bone metastases from primary bone lesions. However, organ specificity of the markers were relatively low.