title: Relationship between lymphocytopenia and circulating tumor cells as prognostic factors for overall survival in metastatic breast cancer.
abstract: BACKGROUND
  Lymphocytopenia and circulating tumor cells (CTCs) have been reported as independent prognostic factors for overall survival (OS) in metastatic breast cancer (MBC), and both have been associated with bone metastases. Our objective was to compare the prognostic significance of lymphocytopenia, CTC count, and extensive bone metastases (> 2 lesions) assessed by fluorine-18 ((18)F) fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in patients with MBC.
  
  
  METHODS
  This is a retrospective study that included patients with MBC who were starting a new line of systemic therapy. The study population consisted of patients treated at the University of Texas MD Anderson Cancer Center between 2004 and 2008 for whom baseline CTC count, lymphocyte counts, and FDG-PET/CT scans were available. Patients were stratified according to estrogen receptor status (positive vs. negative), human epidermal growth factor receptor 2 (HER2) status (amplified vs. constitutive), baseline CTC counts per 7.5 mL of blood (< 5 CTCs/7.5 mL of blood vs. ≥ 5 CTCs/7.5 mL of blood), lymphocytopenia (< 1000 vs. ≥ 1000/μL), and extensive bone metastases (> 2 vs. ≤ 2 lesions).
  
  
  RESULTS
  In 195 assessable patients, the median OS was 27 months (range, 1 to > 45 months). In multivariate analysis, lymphocytopenia, ≥ 5 CTCs/7.5 mL of blood, estrogen receptor status, and line of therapy were the only predictive factors for progression-free survival (PFS) (2P = .001, 2P = .032, 2P = .029, and 2P = .002, respectively) and OS (2P = .001, 2P = .009, 2P = .004, and 2P = .024, respectively).
  
  
  CONCLUSIONS
  CTC measurement and lymphocytopenia are independent prognostic factors for PFS and OS in patients with MBC.
authors.affiliation: Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. u.degiorgi@irst.emr.it
authors.forename: Ugo
authors.initials: U
authors.lastname: De Giorgi
authors.forename: Michal
authors.initials: M
authors.lastname: Mego
authors.forename: Emanuela
authors.initials: E
authors.lastname: Scarpi
authors.forename: Mario
authors.initials: M
authors.lastname: Giuliano
authors.forename: Antonio
authors.initials: A
authors.lastname: Giordano
authors.forename: James M
authors.initials: JM
authors.lastname: Reuben
authors.forename: Vicente
authors.initials: V
authors.lastname: Valero
authors.forename: Naoto T
authors.initials: NT
authors.lastname: Ueno
authors.forename: Gabriel N
authors.initials: GN
authors.lastname: Hortobagyi
authors.forename: Massimo
authors.initials: M
authors.lastname: Cristofanilli
mesh_terms: D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality* / Q000473:pathology*; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008231:Lymphopenia / Q000000981:diagnostic imaging / Q000473:pathology*; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating / Q000473:pathology*; D011379:Prognosis; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D014055:Tomography, Emission-Computed; D014481:United States; D016387:Women's Health
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18