A transient increase in serum procollagen 1 carboxyterminal peptide following effective treatment in prostate cancer patients with bone metastases

Procollagen 1 carboxyterminal peptide (PICP) is thought to be an indicator of new bone formation. The present report demonstrates that effective endocrine therapy induced an initial increase followed by a delayed decrease in serum levels of PICP and alkaline phosphatase in spite of an immediate decrease in serum PSA and PAP and improvement of clinical symptoms in prostate cancer patients with bone metastases. The transient increase in PICP and alkaline phosphatase is a healing reaction and is followed by apparent improvement. Short-term effects of endocrine therapy on prostate cancer patients with bone metastases should be comprehensively evaluated based upon the entire spectrum of clinical and laboratory findings, including serial changes of serum prostate markers and bone markers as well.