title: Detection of CK-19 mRNA-positive cells in the peripheral blood of breast cancer patients with histologically and immunohistochemically negative axillary lymph nodes.
abstract: BACKGROUND
  To investigate the incidence of direct hematogenous spread of cancer cells in patients with early-stage breast cancer by studying the presence of occult tumor cytokeratin-19 (CK-19) mRNA(+) cells in the peripheral blood in relation to the status of sentinel (SLNs) and (ALNs) axillary lymph nodes.
  
  
  METHODS
  SLNs and ALNs from 111 patients with operable stage I-II breast adenocarcinoma were evaluated for the presence of tumor cells by hematoxylin-eosin (H&E) staining and, if negative, by immunohistochemistry (IHC) using an anti-CK-19 antibody. Peripheral blood was also analyzed for the presence of CK-19 mRNA(+) cells by nested RT-PCR, before the initiation of adjuvant treatment and in CK-19 mRNA(+) patients following the completion of adjuvant chemotherapy and hormonal treatment.
  
  
  RESULTS
  After both H&E staining and IHC analysis, 29 (26%) patients were ALN negative (N0). In 78 (70%) patients H&E staining and in four (3.6%) IHC analysis revealed tumors cells, and these patients were considered as ALN positive (N+). Peripheral blood CK-19 mRNA(+) cells were detected in nine (31%) out of 29 N0 and in 31 (38%) out of 82 N + patients (P=0.5) before any adjuvant treatment. Adjuvant chemotherapy and hormone treatment resulted in the disappearance of the CK-19 mRNA(+) cells in all N0 patients and in 15 out of 31 N + patients. After a median follow-up of 40 months, all the N0 CK-19 mRNA(+) patients were relapse-free whereas four (13%) N + CK-19 mRNA(+) patients had relapsed.
  
  
  CONCLUSIONS
  Direct hematogenous dissemination of occult tumor cells may occur in a substantial proportion of patients with early-stage breast cancer. The prognostic implication of the detection of these cells requires long follow-up periods and further studies.
authors.affiliation: Department of Pathology, Medical School, University of Crete, University General Hospital of Heraklion, 71003 Heraklion, Crete, Greece. stath@med.uoc.gr
authors.forename: E N
authors.initials: EN
authors.lastname: Stathopoulos
authors.forename: E
authors.initials: E
authors.lastname: Sanidas
authors.forename: M
authors.initials: M
authors.lastname: Kafousi
authors.forename: D
authors.initials: D
authors.lastname: Mavroudis
authors.forename: J
authors.initials: J
authors.lastname: Askoxylakis
authors.forename: V
authors.initials: V
authors.lastname: Bozionelou
authors.forename: M
authors.initials: M
authors.lastname: Perraki
authors.forename: D
authors.initials: D
authors.lastname: Tsiftsis
authors.forename: V
authors.initials: V
authors.lastname: Georgoulias
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D000328:Adult; D000368:Aged; D000906:Antibodies; D001365:Axilla; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis*; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D021701:Sentinel Lymph Node Biopsy
chemical_list: D000906:Antibodies; D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D007633:Keratins