Diagnostic Assessment of Breast Cancer with a Combination of the 21-Gene Recurrence Score, Clinicopathologic Parameters, and Biomarkers

Abstract

Background: A chemotherapy regimen based on biomarkers in patients might be more efficient than standard therapy. In this study, we evaluated the extensive correlation between the 21-recurrence score (RS), candidate genes, patient demographics, histopathologic factors, and prognosis. We identified the risk factors that affect breast cancer progression, providing evidence for the breast cancer treatment. Methods: In this study, a total of 150 patients were analyzed, all of whom underwent a 21-gene RS score evaluation. The candidate genes evaluated in this study included thymidylate synthase (TYMS), ribonucleotide reductase M1 (RRM1), tubulin beta 3 class III (TUBB3), topoisomerase II alpha (TOP2A), and phosphatase and tensin homolog (PTEN) deleted on chromosome ten. Subsequently, we collected patient information regarding the types of endocrine therapy they received. Results: The 21-gene RS score was significantly correlated with the sentinel lymph node status (p = 0.045). Further investigations into the TYMS and RRM1 genes revealed that the genes are distinct factors involved in the progression of breast cancer. Additionally, human epidermal growth factor receptor 2 (HER2) staining was found to be a compelling indicator of disease progression. Specifically, grade ≥2 staining implies an advanced risk of disease progression. It was demonstrated that the combination of tumor node metastasis (TNM) stage, sentinel lymph node, and 21-gene RS data provides very convincing evidence for clinical application. Moreover, TYMS, RRM1, and HER2 are all independent factors that separately affect the progression of breast cancer. Conclusions: The 21-gene RS was closely associated with the sentinel lymph nodes status in breast cancer. Besides, TYMS, RRM1, and HER2 were identified as independent factors affecting breast cancer progression.