title: Circulating tumor cell isolation during resection of colorectal cancer lung and liver metastases: a prospective trial with different detection techniques.
abstract: BACKGROUND
  Colorectal cancer (CRC) metastasectomy improves survival, however most patient develop recurrences. Circulating tumor cells (CTCs) are an independent prognostic marker in stage IV CRC. We hypothesized that CTCs can be enriched during metastasectomy applying different isolation techniques.
  
  
  METHODS
  25 CRC patients undergoing liver (16 (64%)) or lung (9 (36%)) metastasectomy were prospectively enrolled (clinicaltrial.gov identifier: NCT01722903). Central venous (liver) or radial artery (lung) tumor outflow blood (7.5 ml) was collected at incision, during resection, 30 min after resection, and on postoperative day (POD) 1. CTCs were quantified with 1. EpCAM-based CellSearch® system and 2. size-based isolation with a novel filter device (FMSA). CTCs were immunohistochemically identified using CellSearch®'s criteria (cytokeratin 8/18/19+, CD45- cells containing a nucleus (DAPI+)). CTCs were also enriched with a centrifugation technique (OncoQuick®).
  
  
  RESULTS
  CTC numbers peaked during the resection with the FMSA in contrast to CellSearch® (mean CTC number during resection: FMSA: 22.56 (SEM 7.48) (p = 0.0281), CellSearch®: 0.87 (SEM ± 0.44) (p = 0.3018)). Comparing the 2 techniques, CTC quantity was significantly higher with the FMSA device (range 0-101) than CellSearch® (range 0-9) at each of the 4 time points examined (P < 0.05). Immunofluorescence staining of cultured CTCs revealed that CTCs have a combined epithelial (CK8/18/19) and macrophage (CD45/CD14) phenotype.
  
  
  CONCLUSIONS
  Blood sampling during CRC metastasis resection is an opportunity to increase CTC capture efficiency. CTC isolation with the FMSA yields more CTCs than the CellSearch® system. Future studies should focus on characterization of single CTCs to identify targets for molecular therapy and immune escape mechanisms of cancer cells.
authors: a Program for Liver, Pancreas and Foregut (Lung & Esophageal) Tumors; Department of Surgery (Surgical Oncology).
authors: Jussuf T
authors: JT
authors: Kaifi
authors: Miriam
authors: M
authors: Kunkel
authors: Avisnata
authors: A
authors: Das
authors: Ramdane A
authors: RA
authors: Harouaka
authors: David T
authors: DT
authors: Dicker
authors: Guangfu
authors: G
authors: Li
authors: Junjia
authors: J
authors: Zhu
authors: Gary A
authors: GA
authors: Clawson
authors: Zhaohai
authors: Z
authors: Yang
authors: Michael F
authors: MF
authors: Reed
authors: Niraj J
authors: NJ
authors: Gusani
authors: Eric T
authors: ET
authors: Kimchi
authors: Kevin F
authors: KF
authors: Staveley-O'Carroll
authors: Si-Yang
authors: SY
authors: Zheng
authors: Wafik S
authors: WS
authors: El-Deiry
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary*; D008175:Lung Neoplasms / Q000473:pathology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011446:Prospective Studies
keywords: CRC, Colorectal Cancer; CTCs, Circulating Tumor Cells; EpCAM, Epithelial Cell Adhesion Molecule; FMSA, Flexible Micro Spring Array; circulating tumor cells; colorectal cancer; liver metastasis; lung metastases; stage IV