title: Circulating tumor cells are predictive of poor response to chemotherapy in metastatic gastric cancer.
abstract: BACKGROUND
  The aim of this study was to investigate the impact of number of circulating tumor cells (CTCs) on the treatment outcome for metastatic gastric cancer (GC) following palliative chemotherapy.
  
  
  METHODS
  CTCs were isolated from 7.5 mL of whole blood from 100 patients with metastatic GC by anti-EpCAM antibody coated magnetic particles using the CTC-Profiler (Veridex). Correlations between CTC counts and clinicopathological variables, progression-free survival and overall survival were examined.
  
  
  RESULTS
  Between January 2010 and August 2010, 100 metastatic GC patients were enlisted. Among 100 patients, 5 or more CTCs (CTC-positive) were detected in 27 of 95 patients (28%). Even though the clinical characteristics of the CTC-positive and CTC-negative groups were not significantly different, the treatment response to cytotoxic chemotherapy in the CTC-positive group was significantly poorer (progressive disease: 23.4% vs. 60.0% in CTC-negative vs. CTC-positive group, respectively; p = 0.004). The median progression-free survival of the CTC-positive group was substantially shorter than that of the CTC-negative group (59 days vs. 141 days; p = 0.004). For overall survival, CTC-positive group had significantly shorter survival than CTC-negative group (median OS, 120 days vs. 220 days; p = 0.030). A multivariate Cox proportional hazards regression model showed that CTC positivity was an independent adverse factor for progression-free survival and overall survival.
  
  
  CONCLUSIONS
  This study suggests CTCs are associated with poor response to chemotherapy in metastatic GC-patients.
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Jeeyun
authors.initials: J
authors.lastname: Lee
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Seung Tae
authors.initials: ST
authors.lastname: Kim
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Se Hoon
authors.initials: SH
authors.lastname: Park
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Joon Oh
authors.initials: JO
authors.lastname: Park
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Young Suk
authors.initials: YS
authors.lastname: Park
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Ho Yeong
authors.initials: HY
authors.lastname: Lim
authors.affiliation: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul - Korea.
authors.forename: Won Ki
authors.initials: WK
authors.lastname: Kang
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000401:mortality / Q000556:secondary; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D002166:Camptothecin / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D018572:Disease-Free Survival; D005260:Female; D005472:Fluorouracil / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D000077146:Irinotecan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009360:Neoplastic Cells, Circulating / Q000473:pathology; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D043823:Taxoids / Q000494:pharmacology / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D043823:Taxoids; D000077146:Irinotecan; D005472:Fluorouracil; D002166:Camptothecin