Cross-linked collagen C- and N-telopeptides for an early diagnosis of bone metastasis from breast cancer.

Bone resorption markers have become available for the diagnosis of bone metastasis. We evaluated cross-linked collagen C-and N-telopeptides (ICTP and NTx) in diagnosing bone metastasis from breast cancer. For a threshold of 4.5 ng/ml of 1CTP and 55.0 pmol BCE/micromol of NTx, bone metastasis could be predicted with an accuracy of 84% and 63%, respectively. All the patients who had metastatic lesions, but showed lower than 4.5 ng/ml of ICTP, had a solitary lesion of bone metastasis. Although ICTP is not sensitive enough to detect an early stage of bone metastasis, it is a better biochemical marker than NTx for detecting bone metastasis from breast cancer.