title: Circulating Tumor Cells in Biochemical Recurrence of Prostate Cancer.
abstract: OBJECTIVE
  Circulating tumor cells (CTCs) have known prognostic implications in metastatic castration-resistant prostate cancer, but little is known regarding its utility in biochemical recurrence (BR) of prostate cancer. The primary objectives were to determine whether CTCs are measurable in patients with BR and whether it can reliably predict prostate-specific antigen (PSA) increase and PSA doubling times (PSADTs).
  
  
  METHODS
  BR was identified in patients after prostatectomy or radiation or both, with a PSA increase of ≥ 0.2 for prior prostatectomy or > 2 mg/dL increase for post-nadir in prior radiotherapy. CTCs were enumerated at baseline at the time of study entry using the CellSearch (Janssen Diagnostics, Raritan, NJ) test.
  
  
  RESULTS
  The median age for all 36 patients accrued was 69.5 years (range, 51-91) with a median PSA of 1.65 ng/mL (range, 0.2-65.8). Gleason scores ranged from 5 to 9 (median, 7). The majority had prostatectomy (n = 25), external beam radiotherapy (n = 9), CyberKnife (Accuray, Sunnyvale, CA) (n = 1), and combined radiohormonal therapy (n = 1). PSADT ranged from 0.35 to 55 months, with a median of 7.43 months. The incidence of positive CTCs was 8.3% (3 patients), of whom 2 had biopsy-proven bony lesions on presenting with equivocal scans and PSADTs of 2.27 and 3.08 months, respectively. The third CTC-positive patient had a PSADT of 4.99 months.
  
  
  CONCLUSIONS
  Obtaining CTCs in unselected patients presenting with BR has a relatively low yield. However, obtaining a positive CTC raises the suspicion of the presence of metastatic disease and may have utility for longitudinal follow-ups of patients with BR.
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, The George Washington University Medical Center, Washington, DC. Electronic address: jaragonching@mfa.gwu.edu.
authors.forename: Jeanny B
authors.initials: JB
authors.lastname: Aragon-Ching
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, The George Washington University Medical Center, Washington, DC.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Siegel
authors.affiliation: Department of Urology, The George Washington University Medical Center, Washington, DC.
authors.forename: Harold
authors.initials: H
authors.lastname: Frazier
authors.affiliation: Department of Urology, The George Washington University Medical Center, Washington, DC.
authors.forename: Ramez
authors.initials: R
authors.lastname: Andrawis
authors.affiliation: Department of Urology, The George Washington University Medical Center, Washington, DC.
authors.forename: Frederick
authors.initials: F
authors.lastname: Hendricks
authors.affiliation: Department of Urology, The George Washington University Medical Center, Washington, DC.
authors.forename: Michael
authors.initials: M
authors.lastname: Phillips
authors.affiliation: Department of Urology, The George Washington University Medical Center, Washington, DC.
authors.forename: Thomas
authors.initials: T
authors.lastname: Jarrett
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, The George Washington University Medical Center, Washington, DC.
authors.forename: Hiwot
authors.initials: H
authors.lastname: Guebre-Xabiher
authors.affiliation: Department of Medicine, Duke Cancer Institute, Durham, NC.
authors.forename: Steven
authors.initials: S
authors.lastname: Patierno
authors.affiliation: Department of Epidemiology and Biostatistics, The George Washington University, Washington, DC.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Simmens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery*
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen
keywords: Biochemical recurrence; Circulating tumor cells; PSA doubling times; Prostate cancer; Prostate specific antigen