Serum crosslinked-N-terminal telopeptide of type I collagen (NTx) has prognostic implications for patients with initial prostate carcinoma (PCa): a pilot study.BACKGROUND:  NTx is a type I collagen metabolite previously shown to be increased in patients with bone metastasis. We evaluate NTx potential prognostic role in PCa at diagnosis, when most of the patients have no overt bone involvement. METHODS:  Men with histologic diagnosis of PCa were included at diagnosis. Serum NTx was measured serially every 3 months up to two years by ELISA. Fifty-five PCa patients with a median age of 67 y (51-83 y) were included. Most (86%) had stage I; 4% stage II; 2% stage III and 10% stage IV disease. RESULTS:  At entry, median NTx was 14.65 nMBCE and it did not correlate with age, Gleason score or PSA, but we observed a significant direct correlation with stage (p=0.0094). With a median follow up of 23 months, serum NTx correlated significantly with biochemical recurrence (p=0.012), as did Gleason score (p=0.00056), stage (p=0.012) and PSA (p<0.0001). By multivariate analysis the only 2 independent variables significantly correlated with biochemical recurrence were PSA (p=0.046) and NTx (p=0.021). CONCLUSIONS:  NTx serum concentrations may have a prognostic value in patients with PCa at diagnosis. These results emphasize the importance of bone metabolism biomarkers in patients with PCa even without evident overt bone involvement.