Association between bone scintigraphy and serum levels of tumor markers in the detection of bone disease in breast cancer patients

Purpose: To evaluate the diagnostic value of bone scan in association with measurements of serum CEA, CA 15-3 and TPA levels in breast cancer (BC) patients. Patients and methods: From September 1999 to January 2005, 89 women with BC who had undergone bone scintigraphy as part of their follow-up were retrospectively evaluated. Serum tumor markers levels were compared with the results of bone scintigraphy. Patients with positive bone scans were divided into 3 groups: group 1: 1-3, group 2: 4-5, group 3: >5 bone lesions. Serum CEA, CA 15-3 and TPA levels of 7 ng/ml, 35 U/ml and 90 U/I, respectively, were adopted as the upper limit of normal. Results: Serum CA 15-3 was significantly higher in patients with a positive bone scan (p=0.017). For CEA and TPA, no significant difference was found between patients with and without bone metastases. Twenty-five of 70 patients (36%) with normal CEA had bone metastases. Four of 50 (8%) patients with normal CA 15-3 and 15 of 51 (29%) patients with normal TPA had a positive bone scan. The combination of CA 15-3 with TPA showed 100% sensitivity in detecting bone metastases in all patient subgroups. In all 42 patients without bone metastases, CA 15-3 and/or TPA levels were normal. Conclusion: CA 15-3 but not CEA or TPA is sensitive and specific for the correct determination of bone scintigraphy CA 15-3 plus TPA represent the best combination in association with bone scanning. However, due to frequent false negative results of all tumor markers, it is not recommended to reject a bone scan on the basis of tumor markers levels.