title: Comparison of Oncotype DX Recurrence Score by Histologic Types of Breast Carcinoma.
abstract: BACKGROUND
  Oncotype DX (ODX) is a widely used commercial assay that estimates the risk of distant recurrence and may predict the benefit of chemotherapy in a subset of breast cancers. Some studies have shown the ability to predict Oncotype DX recurrence score (ODXRS), based on routinely reported pathologic features; however, there are limited data correlating specific histologic type of breast cancer to ODXRS.
  
  
  OBJECTIVE
  To compare ODXRS to specific histologic types of breast cancer.
  
  
  METHODS
  One hundred eighty-four cases were sent for ODXRS testing and the results were compared with histologic type and grade.
  
  
  RESULTS
  The highest average ODXRS was seen in invasive ductal carcinoma with micropapillary features (29) followed by invasive ductal carcinoma not otherwise specified (mean = 19.4, SD = 11.6), invasive mucinous carcinoma (mean = 17.2, SD = 5.9), invasive lobular carcinoma (mean = 15.7, SD = 7.2), mixed ductal and lobular carcinoma (mean = 14.1, SD = 7.7), tubular carcinoma (10.0), and mixed ductal and mucinous carcinoma (mean = 8.0, SD = 4.2). Most tumors that had a high ODXRS were grade 3 invasive ductal carcinoma, representing 13 of a total of 20 cases (65%). Interestingly, 3 of the 4 cases of pure invasive mucinous carcinoma had an intermediate ODXRS.
  
  
  CONCLUSIONS
  Although the numbers are small, our findings raise further awareness of the significance between histologic type and grade, and RS in breast cancer. In some special histologic types of breast cancer, particularly those considered to follow either an excellent or poor clinical course by histology alone, it is unclear whether the ODXRS results are as meaningful as in carcinomas of no special type. Further investigation with higher numbers and outcome data is needed.
authors.affiliation: From the Departments of Pathology (Drs Bomeisl and Gilmore), Family Medicine and Community Health (Dr Thompson), and Hematology and Oncology (Dr Harris), University Hospitals Case Medical Center and Case Western Reserve University, Cleveland, Ohio.
authors.forename: Philip E
authors.initials: PE
authors.lastname: Bomeisl
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Thompson
authors.forename: Lyndsay N
authors.initials: LN
authors.lastname: Harris
authors.forename: Hannah L
authors.initials: HL
authors.lastname: Gilmore
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D002288:Adenocarcinoma, Mucinous / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000473:pathology*; D005260:Female; D006801:Humans; D008875:Middle Aged; D060787:Neoplasm Grading; D009364:Neoplasm Recurrence, Local / Q000473:pathology*; D011379:Prognosis; D060888:Real-Time Polymerase Chain Reaction; D012306:Risk