Yuka Matsuura

Prospective Study of Urinary and Serum Cross-Linked N-Telopeptide of Type I Collagen (NTx) for Diagnosis of Bone Metastasis in Patients With Lung Cancer

BACKGROUND Many cancers metastasize to bone, which may cause an increase in bone resorption because of the direct effects of the tumor itself or osteoclastic activation. PATIENTS AND METHODS Levels of urinary cross-linked N-telopeptide of type I collagen (uNTx) and serum cross-linked N-telopeptide of type I collagen (sNTx) were measured in 100 patients with lung cancer and 50 patients with benign respiratory disease using the Osteomark NTx urine and serum assays (Osteomark, Princeton, NJ). Bone metastasis was diagnosed by bone scintigraphy. Receiver operating characteristic (ROC) analysis was used to evaluate the detection of bone metastasis. Sensitivity and specificity to detect bone metastasis were calculated when cutoff points were set to 64 nmol bone collagen equivalents (BCE)/mmol Cr for uNTx and 22 nmol BCE/L for sNTx. RESULTS Patients with lung cancer and bone metastasis had significantly higher levels of both uNTx and sNTx (uNTx median [range], 61.3 [22.7-593.1] nmol BCE/mmol creatinine [Cr]; sNTx median [range], 19.7 [10.7-97.1] nmol BCE/L) than did patients with lung cancer without bone metastasis (uNTx median [range], 45.2 [19.8-153.0] nmol BCE/mmol Cr; sNTx median [range], 16.7 [11.0-28.4] nmol BCE/L), or patients with benign respiratory diseases (uNTx median [range], 40.6 [15.2-155.9] nmol BCE/mmol Cr; sNTx median [range], 14.8 [9.5-55.5] nmol BCE/L.). There was good correlation between uNTx and sNTx (R = 0.807). Area under the curve (AUC) for ROC was 0.743 for uNTx and 0.712 for sNTx. The sensitivity and specificity for the diagnosis of bone metastasis were 48.0% and 86.0%, respectively, using uNTx, and 40.0% and 87.0%, respectively, using sNTx. CONCLUSION This prospective study indicates equivalency between sNTx and uNTx in sensitivity and specificity to detect bone metastasis, and both uNTx and sNTx may have value as aids in the diagnosis of bone metastasis in patients with lung cancer.

Therapy-related Leukemia as a Result of Long-term Chemotherapy for Non-small Cell Lung Cancer

背景．近年，化学療法の発達に伴い肺癌患者において長期生存例が増加してきている．一方化学療法後治療関連白血病を発症する例が報告されている．症例．64歳女性．2004年肺腺癌（T4N0M0 stage IIIB）の診断にて，プラチナ製剤を含む各種化学療法を2004年から2009年までの間に受けた．また2008年に転移性脳腫瘍に対する放射線療法を受けた．2009年1月微熱と倦怠感が続くため当院を受診し，遷延性の好中球減少を認めたため入院となった．入院後の末梢血で芽球の増加を認めたため骨髄穿刺を実施し，急性骨髄性白血病と診断した．本症例は長期間にわたる化学療法，放射線治療の経過中に白血病を発症したことから治療関連白血病と考えた．結論．治療関連白血病は肺癌患者において，治療が長期化する場合には留意すべきであると考えられる．