Diagnostic value of bone-turnover metabolites in the diagnosis of bone metastases in patients with lung carcinoma.
BACKGROUND
Several biochemical markers of bone formation and bone resorption have been developed recently. The authors evaluated the usefulness of new biomarkers, such as urinary deoxypyridinoline (D-PYD), serum pyridinoline cross-linked C-telopeptides of Type I collagen (1CTP), and urinary pyridinoline cross-linked N-telopeptides of Type I collagen (NTx), in the assessment of bone metastases in patients with lung carcinoma.


METHODS
The serum concentrations of 1CTP and the urinary concentrations of D-PYD and NTx were measured in 100 lung carcinoma patients, of whom 20 patients had bone metastases and 80 patients did not. Receiver operating characteristic (ROC) curves were drawn for these markers to compare their usefulness in detecting bone metastases originating in lung carcinoma.


RESULTS
Urinary concentrations of NTx in patients with bone metastases were significantly greater than in patients without bone metastases (147.1 +/- 129.3 pmol bone collagen equivalents [BCE]/micromol Cr vs. 47.2 +/- 29.9 pmol BCE/micromol Cr; P < 0.0001). Urinary concentrations of D-PYD in patients with bone metastases also were significantly greater than in patients without bone metastases (10.0 +/- 3.6 BCE/micromol Cr vs. 6.6 +/- 2.2 pmol BCE/micromol Cr; P = 0.0001). No significant difference was observed in serum concentrations of 1CTP between patients with and without bone metastases. A moderate but significant correlation was seen between NTx and D-PYD (correlation coefficient [R] = 0.435; P < 0.0001) and between D-PYD and 1CTP (R = 0.525; P < 0.0001). NTx had a better ROC curve than D-PYD and 1CTP (the areas under the ROC curve were 0.84, 0.79, and 0.62, respectively). Using the threshold of 62.5 pmol BCE/micromol Cr for NTx, sensitivity, specificity, and accuracy were 0.800, 0.737, and 0.750, respectively.


CONCLUSIONS
In the current study, the measurement of NTx appeared to be most useful as a marker of bone metastases in patients with lung carcinoma.
Izumi
M
M
Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Nakanishi
Y
Y
Takayama
K
K
Kimotsuki
K
K
Inoue
K
K
Wataya
H
H
Minami
T
T
Hara
N
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000652:urine; D014408:Biomarkers, Tumor / Q000032:analysis*; D001859:Bone Neoplasms / Q000175:diagnosis / Q000556:secondary*; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000556:secondary*; D018288:Carcinoma, Small Cell / Q000175:diagnosis / Q000556:secondary*; D003094:Collagen / Q000097:blood / Q000652:urine; D024042:Collagen Type I; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000097:blood / Q000652:urine; D012680:Sensitivity and Specificity
D000596:Amino Acids; D014408:Biomarkers, Tumor; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; C036020:deoxypyridinoline; D003094:Collagen