Breast cancer-specific survival in >4,600 patients with lymph node-positive (LN+) hormone receptor-positive (HR+) invasive breast cancer (BC) and 21-gene recurrence score® (RS) results in the SEER registries

Background

The 21-gene RS assay has been shown to predict BC recurrence and adjuvant chemotherapy benefit in LN + , HR + , HER2-negative BC. We assessed 5-year BC-specific survival (BCSS) in LN+ patients with 21-gene RS results in the SEER registries, a cancer surveillance program that covers 30% of the US population.

Methods

All SEER BC cases diagnosed 2004-2012 were linked to 21-gene assays performed by the Genomic Health Clinical Laboratory. The analysis was restricted to single primary invasive BC, LN + , no distant metastases, HR+ (per SEER), HER2-negative (per RT-PCR). Using the actuarial method in SEER*Stat, BCSS was assessed for those who were diagnosed 2004-2011 with survival follow-up through 2012, by RS category and by number of positive nodes.

Results

The proportion of women with LN + , HR+ BC who had RS results (n = 7695) increased over time between 2004 (0.3%, n = 33) and 2012 (13.8%, n = 2010), and was lower with increasing nodal involvement, from micrometastases only (36.0%, n = 792) to 4+ nodes (2.6%, n = 81) in 2012. BCSS differed significantly by both RS category (log-rank p 

Conclusions

Overall, 5-year BCSS is excellent in patients with RS

Clinical trial identification

N/A

Legal entity responsible for the study

Dave P. Miller, Megan Roberts, Lynne Penberthy

Funding

National Cancer Institute

Disclosure

D.P. Miller, S. Shak: Employed by Genomic Health; stock ownership in Genomic Health

All other authors have declared no conflicts of interest.