TY - JOUR

T1 - Prediction of the Oncotype DX recurrence score

T2 - Use of pathology-generated equations derived by linear regression analysis

AU - Klein, Molly E.

AU - Dabbs, David J.

AU - Shuai, Yongli

AU - Brufsky, Adam M.

AU - Jankowitz, Rachel

AU - Puhalla, Shannon L.

AU - Bhargava, Rohit

N1 - Funding Information:
We thank Ms Diane Bell for secretarial assistance. This project used the UPCI Biostatistics Facility and was supported in part by award P30CA047904.

PY - 2013/5

Y1 - 2013/5

N2 - Oncotype DX is a commercial assay frequently used for making chemotherapy decisions in estrogen receptor (ER)-positive breast cancers. The result is reported as a recurrence score ranging from 0 to 100, divided into low-risk (<18), intermediate-risk (18-30), and high-risk (≥31) categories. Our pilot study showed that recurrence score can be predicted by an equation incorporating standard morphoimmunohistologic variables (referred to as original Magee equation). Using a data set of 817 cases, we formulated three additional equations (referred to as new Magee equations 1, 2, and 3) to predict the recurrence score category for an independent set of 255 cases. The concordance between the risk category of Oncotype DX and our equations was 54.3%, 55.8%, 59.4%, and 54.4% for original Magee equation, new Magee equations 1, 2, and 3, respectively. When the intermediate category was eliminated, the concordance increased to 96.9%, 100%, 98.6%, and 98.7% for original Magee equation, new Magee equations 1, 2, and 3, respectively. Even when the estimated recurrence score fell in the intermediate category with any of the equations, the actual recurrence score was either intermediate or low in more than 80% of the cases. Any of the four equations can be used to estimate the recurrence score depending on available data. If the estimated recurrence score is clearly high or low, the oncologists should not expect a dramatically different result from Oncotype DX, and the Oncotype DX test may not be needed. Conversely, an Oncotype DX result that is dramatically different from what is expected based on standard morphoimmunohistologic variables should be thoroughly investigated.

AB - Oncotype DX is a commercial assay frequently used for making chemotherapy decisions in estrogen receptor (ER)-positive breast cancers. The result is reported as a recurrence score ranging from 0 to 100, divided into low-risk (<18), intermediate-risk (18-30), and high-risk (≥31) categories. Our pilot study showed that recurrence score can be predicted by an equation incorporating standard morphoimmunohistologic variables (referred to as original Magee equation). Using a data set of 817 cases, we formulated three additional equations (referred to as new Magee equations 1, 2, and 3) to predict the recurrence score category for an independent set of 255 cases. The concordance between the risk category of Oncotype DX and our equations was 54.3%, 55.8%, 59.4%, and 54.4% for original Magee equation, new Magee equations 1, 2, and 3, respectively. When the intermediate category was eliminated, the concordance increased to 96.9%, 100%, 98.6%, and 98.7% for original Magee equation, new Magee equations 1, 2, and 3, respectively. Even when the estimated recurrence score fell in the intermediate category with any of the equations, the actual recurrence score was either intermediate or low in more than 80% of the cases. Any of the four equations can be used to estimate the recurrence score depending on available data. If the estimated recurrence score is clearly high or low, the oncologists should not expect a dramatically different result from Oncotype DX, and the Oncotype DX test may not be needed. Conversely, an Oncotype DX result that is dramatically different from what is expected based on standard morphoimmunohistologic variables should be thoroughly investigated.

KW - ER/PR/HER2/Ki-67

KW - Oncotype DX recurrence score prediction

KW - breast cancer

KW - immunohistochemistry

KW - morphology

UR - http://www.scopus.com/inward/record.url?scp=84877016055&partnerID=8YFLogxK

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U2 - 10.1038/modpathol.2013.36

DO - 10.1038/modpathol.2013.36

M3 - Article

C2 - 23503643

AN - SCOPUS:84877016055

SN - 0893-3952

VL - 26

SP - 658

EP - 664

JO - Modern Pathology

JF - Modern Pathology

IS - 5

ER -