The Oncotype DX breast recurrence score assay was the first genomic test available in the NHS to guide clinical decision-making regarding adjuvant chemotherapy for patients with oestrogen receptor-positive (ER+), human epidermal growth factor 2-negative (HER2-) breast cancer.
A new study published in the journal Breast Cancer Research and Treatment, retrospectively collected data on recurrence scores (RS), patient and tumour characteristics, and adjuvant therapy for 713 patients from 14 UK cancer centres. Risk by RS-pathology-clinical (RSPC) was calculated.
The risk of recurrence was 49.8%, 36.2%, and 14% for low (RS <18), intermediate (RS 18-30) and high (RS >30), respectively.
Overall, 26.7% received adjuvant chemotherapy. Over 49% of those were RS >30, and 93.3% were RS >25.
Concordance between RS and RSPC improved when intermediate risk was defined as RS 11-25.
This real-world data demonstrates the value of genomic tests in reducing the use of adjuvant chemotherapy in breast cancer, the authors say. They add that incorporating clinical characteristics or RSPC scores gives additional prognostic information which may also aid decision making.
