title: Trastuzumab decreases the incidence of clinical relapses in patients with early breast cancer presenting chemotherapy-resistant CK-19mRNA-positive circulating tumor cells: results of a randomized phase II study.
abstract: BACKGROUND
  Since the detection of circulating tumor cells (CTCs) which express HER2 is an adverse prognostic factor in early breast cancer patients, we investigated the effect of trastuzumab on patients' clinical outcome.
  
  
  METHODS
  Seventy five women with HER2 (-) breast cancer and detectable CK19 mRNA-positive CTCs before and after adjuvant chemotherapy, were randomized to receive either trastuzumab (n=36) or observation (n=39). CK19 mRNA-positive CTCs were detected by RT-PCR and double stained CK(+)/HER2(+) cells by immunofluorescence. The primary endpoint was the 3-year disease-free survival rate.
  
  
  RESULTS
  Fifty-one (89%) of the 57 analyzed patients had HER2-expressing CTCs. After trastuzumab administration, 27 of 36 (75%) women became CK19 mRNA-negative compared to seven of 39 (17.9%) in the observation arm (p=0.001). After a median follow up time of 67.2 months, four (11%) and 15 (38%) relapses were observed in the trastuzumab and observation arm, respectively (p=0.008); subgroup analysis indicated that this effect was mainly confined to women with >3 involved axillary lymph nodes (p=0.004). The median DFS was also significantly higher for the trastuzumab-treated patients (p=0.008).
  
  
  CONCLUSIONS
  Administration of trastuzumab can eliminate chemotherapy-resistant CK19 mRNA-positive CTCs, reduce the risk of disease recurrence and prolong the DFS.
authors.affiliation: Department of Medical Oncology, University Hospital of Heraklion, and Medical School, University of Crete, Heraklion, Crete, Greece. georgsec@med.uoc.gr
authors.forename: V
authors.initials: V
authors.lastname: Georgoulias
authors.forename: V
authors.initials: V
authors.lastname: Bozionelou
authors.forename: S
authors.initials: S
authors.lastname: Agelaki
authors.forename: M
authors.initials: M
authors.lastname: Perraki
authors.forename: S
authors.initials: S
authors.lastname: Apostolaki
authors.forename: G
authors.initials: G
authors.lastname: Kallergi
authors.forename: K
authors.initials: K
authors.lastname: Kalbakis
authors.forename: A
authors.initials: A
authors.lastname: Xyrafas
authors.forename: D
authors.initials: D
authors.lastname: Mavroudis
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D000328:Adult; D000368:Aged; D061067:Antibodies, Monoclonal, Humanized / Q000494:pharmacology / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000097:blood / Q000188:drug therapy* / Q000473:pathology; D018572:Disease-Free Survival; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D053539:Keratin-19 / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control*; D009360:Neoplastic Cells, Circulating / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D000068878:Trastuzumab
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D053539:Keratin-19; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human