title: Clinical experience of using Oncotype DX as an additional treatment decision tool in early breast cancer - a retrospective analysis from 5 Greek institutions.
abstract: OBJECTIVE
  The objective of this retrospective study was to describe the results from five institutions' experience of using Oncotype DX(®) to identify patients who need chemotherapy despite the presence of primarily favorable characteristics.
  
  
  METHODS
  Oncotype DX was performed in 106 pre- and postmenopausal patients with estrogen receptor-positive, HER2-negative, early breast cancer with a combination of favorable prognostic factors or favorable prognostic factors with at least one unfavorable characteristic (tumor size >2 cm, tumor grading of II-III, Ki-67 ≥ 10%, presence of lymph node micrometastases) in which it was unclear whether hormonal therapy only or chemotherapy plus hormonal therapy was the optimal adjuvant treatment.
  
  
  RESULTS
  Sixty-four (60.4%) women had Recurrence Score (RS) values <18, 29 (27.4%) intermediate RS values of 18-30, and 13 (12.3%) high RS values of ≥31. Tumor size, grading and presence of micrometastases were not associated with the RS. There was a significant association between Recurrence Score and the number of unfavorable characteristics as a categorical but not as a continuous variable. High Recurrence Scores were predictive of high Ki-67 but the converse was not true. Overall, 29 of 106 (27.4%) patients received chemotherapy because of an intermediate or a high Recurrence Score.
  
  
  CONCLUSIONS
  The Recurrence Score helped in treatment decision-making for estrogen receptor-positive, HER2-negative patients with favorable characteristics or an intermediate risk of recurrence due to the presence of at least one unfavorable factor. The results of the 21-gene assay increased the likelihood for patients with intermediate clinical and histopathological risk factors receiving chemotherapy.
authors.affiliation: Hellenic Society of Breast Surgeons, 6 Eslin Street, 11523 Athens, Greece. cmbreast@yahoo.gr
authors.forename: C
authors.initials: C
authors.lastname: Markopoulos
authors.forename: Gr
authors.initials: G
authors.lastname: Xepapadakis
authors.forename: V
authors.initials: V
authors.lastname: Venizelos
authors.forename: A
authors.initials: A
authors.lastname: Tsiftsoglou
authors.forename: J
authors.initials: J
authors.lastname: Misitzis
authors.forename: D
authors.initials: D
authors.lastname: Panoussis
authors.forename: Z
authors.initials: Z
authors.lastname: Antonopoulou
authors.forename: M
authors.initials: M
authors.lastname: Stathoulopoulou
authors.forename: V
authors.initials: V
authors.lastname: Zobolas
authors.forename: H
authors.initials: H
authors.lastname: Gogas
mesh_terms: D000328:Adult; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D003657:Decision Making; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis; D008207:Lymphatic Metastasis; D008499:Medical Records; D008875:Middle Aged; D060787:Neoplasm Grading; D009363:Neoplasm Proteins / Q000032:analysis*; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control*; D011237:Predictive Value of Tests; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis; D012189:Retrospective Studies
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; C508053:ERBB2 protein, human