title: Circulating tumor cell as a diagnostic marker in primary lung cancer.
abstract: OBJECTIVE
  To investigate the diagnostic performance of circulating tumor cells (CTC) in discrimination between primary lung cancer and nonmalignant diseases as well as in prediction of distant metastasis.
  
  
  METHODS
  We prospectively evaluated CTCs in 7.5-mL samples of peripheral blood sampled from patients with a suspicion or a diagnosis of primary lung cancer. A semiautomated system was used to capture CTCs with an antibody against epithelial cell adhesion molecule.
  
  
  RESULTS
  Of 150 eligible patients, 25 were finally diagnosed as having nonmalignant disease, and 125 were diagnosed as having primary lung cancer with (n = 31) or without (n = 94) distant metastasis. CTCs were detected in 30.6% of lung cancer patients and in 12.0% of nonmalignant patients. CTC count was significantly higher in lung cancer patients than in nonmalignant patients, but a receiver operating characteristic (ROC) curve analysis showed an insufficient capability of the CTC test in discrimination between lung cancer and nonmalignant diseases with an area under ROC curve of 0.598 (95% confidence interval, 0.488-0.708; P = 0.122). Among lung cancer patients, CTC count significantly increased along with tumor progression, especially with development of distant metastasis. The area under ROC curve for CTC count in prediction of distant metastasis was 0.783 (95% confidence interval, 0.679-0.886; P < 0.001). When patients with one or more CTCs were judged as having metastatic disease, sensitivity and specificity of the CTC test were 71.0% and 83.0%, respectively.
  
  
  CONCLUSIONS
  CTC is a useful surrogate marker of distant metastasis in primary lung cancer.
authors.affiliation: Departments of Thoracic Surgery, Pathology, and Thoracic Oncology, and Division of Respiratory Medicine, Department of Internal Medicine, Hyogo College of Medicine, Hyogo, Japan. ftanaka@hyo-med.ac.jp
authors.forename: Fumihiro
authors.initials: F
authors.lastname: Tanaka
authors.forename: Kazue
authors.initials: K
authors.lastname: Yoneda
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kondo
authors.forename: Masaki
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Teruhisa
authors.initials: T
authors.lastname: Takuwa
authors.forename: Seiji
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Yoshitomo
authors.initials: Y
authors.lastname: Okumura
authors.forename: Shakibur
authors.initials: S
authors.lastname: Rahman
authors.forename: Noriaki
authors.initials: N
authors.lastname: Tsubota
authors.forename: Tohru
authors.initials: T
authors.lastname: Tsujimura
authors.forename: Kozo
authors.initials: K
authors.lastname: Kuribayashi
authors.forename: Kazuya
authors.initials: K
authors.lastname: Fukuoka
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
authors.forename: Seiki
authors.initials: S
authors.lastname: Hasegawa
mesh_terms: D000951:Antigens, Neoplasm / Q000378:metabolism; D019540:Area Under Curve; D001331:Automation; D018450:Disease Progression; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood* / Q000175:diagnosis*; D008495:Medical Oncology / Q000379:methods; D009362:Neoplasm Metastasis; D009360:Neoplastic Cells, Circulating; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve
chemical_list: D000951:Antigens, Neoplasm