Estimating Oncotype DX® Recurrence Score

Equations Input and Results

Once all information is present, it should be inserted in their respective fields. Once all necessary fields have valid values, all three Magee Equations will automatically calculate.
Nottingham
Score


3 to 9
ER
H-Score

0 to 300
PR
H-Score

0 to 300
HER2

Tumor Size

cm
KI-67
Percentage
%
Equation 1 Result
 
Equation 2 Result
 
Equation 3 Result
 

Background

Oncotype DX® (Genomic Health Inc. Redwood City, CA), is a commercial assay, frequently used by oncologists for making chemotherapy decisions. It is a quantitative reverse transcription polymerase chain reaction based assay, used to estimate the risk of distant recurrence for patients with ER positive, lymph node negative breast cancers. It is reported as a numerical score (recurrence score or RS) ranging from 0-100 and divided into low risk (LR; <18), intermediate risk (IR; 18-30), and high risk (HR; ≥31) categories. In a pilot study from this institution, it was reported that standard histopathologic factors and immunohistochemical markers can be used to estimate the recurrence score (original Magee equation; Mod Pathol. 2008;21:1255-1261). Subsequently, new Magee Equations have been derived using a much larger database of over 800 cases that were sent for clinical oncotype DX® testing to Genomic Health as per oncologistsí request. These new Magee Equations have been validated on a separate set of over 200 cases, again sent for clinical oncotype DX® testing to Genomic Health as per oncologistsí request.

How the New Magee Equations Were Derived

Multiple linear regression analysis was performed to model the prediction of the oncotype DX® RS by Nottingham Score (range 3-9), Ki-67 labeling index (0-100), tumor size (in cm.), H-scores (range: 0-300) for ER and PR, and HER2 status (negative, equivocal or positive). Three models were built based on different hypotheses and data availability. The first regression model included all available parameters (including Ki-67 index) for prediction of oncotype DX® RS. The second regression model was similar to the first but did not include Ki-67. The third regression model included only semi-quantitative immunohistochemical expression levels for ER, PR, HER2 and Ki-67.

How to Use the Equations

All the required data is generally present in the surgical pathology report. The hormone receptor results will require the semi-quantitative H-score. If not reported initially, this can be easily calculated by the case pathologist by reviewing the immunohistochemical (IHC) stain slides. HER2 status should be classified as shown below.
  • HER2 negative: HER2 IHC score 0, IHC score 1+, and IHC score 2+ with negative HER2 FISH
  • HER2 positive: HER2 IHC score of 3+, and HER2 IHC score of 2+ with unequivocal amplification for HER2 by FISH
  • HER2 equivocal: HER2 IHC score of 2+ with equivocal HER2 result by FISH
Once all information is present, it should be inserted in their respective fields. Once all necessary fields have valid values, all three Magee Equations will automatically calculate.

Reference

Klein ME, Dabbs DJ, Shuai Y, Brufsky AM, Jankowitz R, Puhalla SL, Bhargava R. Prediction of the Oncotype DX® Recurrence Score: Use of Pathology Generated Equations Derived by Linear Regression Analysis. Mod Pathol. 2013. PMID: 23503643.

Disclaimer

University of Pittsburgh Physicians, Magee-Womens Hospital and UPMC and each of their affiliates have no financial or other relationship with Genomic Health Inc. The Magee Equations should only be used by medical professionals who understand its usefulness and limitations. Medical professionals should use these equations at their own discretion and this information should not be used for the diagnosis or treatment of any health problem or disease. The information is not intended to replace clinical judgment or guide individual patient care in any manner and is not provided in the course of a professional relationship between a health care provider and a patient. University of Pittsburgh Physicians, Magee-Womens Hospital and UPMC and each of their affiliates are not liable for any direct, indirect, incidental, special, consequential or punitive damages arising in any way from the actions taken by medical professionals based on the estimated recurrence score calculated by Magee Equations or any other information set forth herein. University of Pittsburgh Physicians, Magee-Womens Hospital and UPMC and each of their affiliates hereby disclaim any warranty of any kind, express or implied, including but not limited to the implied warranties of title, noninfringement, merchantability and fitness for a particular use or purpose.