N-telopeptide of type I collagen is useful for monitoring therapeutic response in non-small cell lung cancer patients with bone metastases.
BACKGROUND
Elevated levels of N-telopeptide of type I collagen (NTX) are associated with skeletal-related events and death. However, it is unclear whether NTX is useful for monitoring therapeutic response in non-small cell lung cancer (NSCLC) patients with bone metastases.


METHODS
Urinary NTX levels were assessed at baseline and after one cycle of chemotherapy in 30 NSCLC patients with bone metastases. NTX levels were categorized as normal (NTX <64 nmol/mmol creatinine) or high (NTX ≥64 nmol/mmol creatinine).


RESULTS
In 30 patients, the median NTX level at 1 month was significantly lower than that at baseline (P = 0.0016). The NTX levels after treatment were significantly lower than those at baseline in 20 patients with partial response (n = 2) or stable disease (n = 18). However, no significant difference of the NTX levels was observed in 10 patients with progressive disease. Sixteen (53.3%) of 30 patients had high baseline NTX levels. Ten patients had normal NTX levels after one cycle of chemotherapy, whereas 6 patients also had high NTX levels after treatment. The 10 patients with normal NTX levels had significantly better prognosis than the 6 patients with high NTX levels.


CONCLUSIONS
Urinary NTX levels at 1 month after chemotherapy may be useful for predicting therapeutic response in NSCLC patients with bone metastases. Normalization of elevated baseline NTX at 1 month after chemotherapy was associated with survival benefits.
Kaira
Rieko
R
Division of Thoracic Oncology, Shizuoka Cancer Center, 1007 Shimonagakubo, Nagaizumi-cho, Sunto-gun, Shizuoka, 411-8777, Japan.
Murakami
Haruyasu
H
Kaira
Kyoichi
K
Takahashi
Toshiaki
T
Tsuya
Asuka
A
Nakamura
Yukiko
Y
Naito
Tateaki
T
Endo
Masahiro
M
Yamamoto
Nobuyuki
N
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000652:urine*; D001859:Bone Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary / Q000652:urine; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary / Q000652:urine; D024042:Collagen Type I / Q000652:urine*; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010455:Peptides / Q000652:urine*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D013997:Time Factors; D016896:Treatment Outcome
D014408:Biomarkers, Tumor; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide