SABCS 2011: New Test Predicts Risk for Recurrence for Patients with DCIS
A multigene test can differentiate lower-risk and more aggressive forms of ductal carcinoma in situ (DCIS), according to results presented at the 34th Annual CTRC-AACR San Antonio Breast Cancer Symposium. In a collaboration between the Eastern Cooperative Oncology Group (ECOG), North Central Cancer Treatment Group and Genomic Health, researchers used the Oncotype DX breast cancer assay and a new, prespecified DCIS Score™ to predict recurrence using an optimized gene expression algorithm.
In this study, Dr. Lawrence Solin and colleagues tested and scored primary tumor samples from 327 patients with DCIS treated with surgical excision without irradiation (some of whom received tamoxifen). The primary objective was to determine whether there was a significant association between the risk of an ipsilateral breast event (IBE) and the continuous DCIS Score. After a median follow-up of 8.8 years, 46 patients had an IBE (defined as ipsilateral local recurrence of DCIS [n=20] or invasive cancer [n=26]).
Continuous DCIS Score was significantly associated with IBE (HR=2.34 per 50 units; 95% CI=1.15 – 4.59) when adjusted for tamoxifen use and with invasive IBE (HR=3.73; 95% CI=1.34 – 9.82). According to the researchers, “We have prospectively validated a multigene assay that quantifies recurrence risk and complements traditional clinical and pathologic factors in selected patients with DCIS treated with surgical excision without irradiation. The DCIS Score provides a new clinical tool for individualized selection of treatment for patients with DCIS.”