Preoperative serum pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen level predicts postoperative distant metastasis in patients with non-small-cell lung cancer.

OBJECTIVES To examine the relationship between preoperative serum pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (I-CTP) levels and postoperative distant metastasis in patients with non-small-cell lung cancer (NSCLC). METHODS We retrospectively reviewed 143 patients in whom preoperative serum I-CTP level was measured from January 2006 to March 2011, including 91 males and 52 females with an average age of 70.1 ± 8.2 years. Histological subtypes included adenocarcinoma (n = 95), squamous cell carcinoma (n = 34) and other (n = 14). Preoperative serum carcinoembryonic antigen (CEA) and cytokeratin-19 fragment (CYFRA) levels were also measured. Patients with abnormal renal function or preoperative bone fractures were excluded. RESULTS The mean preoperative serum I-CTP level was 4.1 ± 1.6 ng/ml, and the preoperative serum I-CTP level was elevated (>4.5 ng/ml) in 29 patients. Distant metastasis was detected in 21 patients during the 39 ± 18 (range 1-79) months of follow-up. The rate of distant metastasis was significantly higher in patients with elevated preoperative serum I-CTP levels than those with normal preoperative I-CTP levels (≤4.5 ng/ml) (P < 0.0001). The 5-year recurrence-free survival rate was lower in patients with elevated preoperative serum I-CTP levels than those with normal preoperative I-CTP levels (41.8 vs 92.9%; P < 0.0001). CONCLUSIONS An elevated preoperative serum I-CTP level predicts postoperative distant metastasis in patients with NSCLC.