[274] Correlation of Oncotype Dx Recurrence Score with Pathological Characteristics and Semiquantitative ER, PR and HER-2 Expression Score in Breast Cancer.

Renu K Virk, Reema Jaffar, Dina Kandil, Robert M Quinlan, Ashraf Khan. UMass Memorial Medical Center, Worcester, Ma; Children's Memorial Hospital, Northwestern University, Chicago, IL; UMass MemorialMedical Center, Worcester, Ma

Background: Stage I & II, estrogen receptor (ER) positive, HER-2 negative, breast cancer is often submitted for a 21-gene set expression profile by reverse transcriptase polymerase chain reaction (RT-PCR) commercially available as Oncotype Dx (Genomic Health, Redwood City, CA). This test helps classifying breast tumors into high risk, intermediate risk and low risk of recurrence, which guides in planning adjuvant therapy. In this study, we aimed to correlate pathologic characteristics of the tumor and semi-quantitative hormone receptor and HER-2 status with the Oncotype Dx recurrence score.
Design: We retrieved all cases from our archives sent for Oncotype Dx over the past 4 years. The tumor characteristics, including size, grade, lymphovascular invasion (LVI), necrosis, ER, progesterone receptor (PR) and HER-2 status were tabulated. A total of 238 cases were identified and stratified according to the Oncotype Dx recurrence score. ER immunoreactivity was graded into 4 groups: 1 with 2-10%, 2 with 11-25%, 3 with 26-75% and 4 with >75% tumor cell nuclei positive. PR immunoreactivity was graded into 5 groups: 0 with <2%, 1 with 2-10%, 2 with 11-25%, 3 with 26-75% and 4 with >75% tumor cell nuclei positive. HER-2 evaluation was done by image analysis using Advanced Chromavision Imaging System (ACIS) and expression was divided into 3 groups, group 1 with a score of 0, 2 with scores of 0.1 to 1.0 and 3 with scores of 1.1 and above. Statistical analysis was performed using chi square test.
Results: As shown in table 1, there was statistically significant correlation between Oncotype Dx recurrence score and tumor grade, necrosis, ER, PR and HER-2 immunoreactivity scores.

Table 1
 Oncotype Dx Recurrence Scorep value
# CasesHighLow 
Tumor grade   
I141 
II1977 
III912p=0.0015
Necrosis   
Present99 
Absent20127p=0.0026
ER grade   
143 
201 
356 
419121p=0.0015
PR grade   
014 
1119 
2411 
3528 
4779p=0.0001
HER-2 score   
1531 
2849 
31654 



Conclusions: In breast cancer low ER, PR and high HER-2 immunoexpression scores together with high grade, and presence of necrosis are associated with a high Oncotype recurrence score and may be useful in planning adjuvant chemotherapy if Oncotype Dx test is not available.
Category: Breast

Wednesday, March 2, 2011 9:30 AM

Poster Session V # 8, Wednesday Morning

 

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