Prospective evaluation of the impact of the 21-gene recurrence score® assay on adjuvant treatment decisions for women with node-positive breast cancer in Ontario, Canada

Background

The 21-gene Recurrence Score^® (RS) assay is reimbursed by the single payer Ontario Health Ministry for node-negative early-stage breast cancer (EBC). We carried out a prospective study to evaluate the impact of the RS^® assay on treatment decisions for women with node-positive (N+), estrogen receptor-positive (ER+) EBC.

Methods

Women with ER + , human epidermal growth factor receptor 2-negative, EBC and 1-3 positive axillary lymph nodes, who were candidates for adjuvant chemotherapy (CT), in addition to hormonal treatment, were eligible. Primary objective was to characterize how the results of the RS assay impacted decision making processes of medical oncologists by evaluating recommendations for adjuvant therapy prior to and after the RS assay. Secondary objectives were to characterize changes in physician level of confidence in their recommendation, whether the results of the RS assay affected patients' preferences and level of confidence in treatment recommendations, and to evaluate the actual treatment administered.

Results

From October 2014 to May 2016, 68 patients were recruited (target:70 patients); RS assay results are currently available for 64 patients. Mean age was 61 (range: 41-84); 70% were post-menopausal. Tumor size was ≤2 cm in 47%, >2-5 cm in 45% and >5cm in 8%. Tumors were grade 1 in 22%, grade 2 in 58% and grade 3 in 20%. RS was low (

Conclusions

The RS assay resulted in a substantial decrease in the number of N+ patients who would receive CT and in an increase of the physicians' and patients' confidence in the adjuvant treatment recommendations.

Clinical trial identification

NCT02347449 First received: November 17, 2014 Last updated: January 4, 2016 Last verified: January 2016

Legal entity responsible for the study

Sunnybrook Odette Cancer Centre

Funding

Genomic Health, Inc

Disclosure

S. Torres: Received fellowship support from Genomic Health. C. Chao: Senior Director, Medical Affairs at Genomic Health, Inc. Stock ownership in Genomic Health Inc. A. Eisen: Principle investigator of the present study. All other authors have declared no conflicts of interest.