Attempt to Substitute the Oncotype DX Breast Recurrence Score ® Test by Histopathological Factors and MUC1 Protein Expression

• Published in: Cancer diagnosis & prognosis 2024-07, Vol.4 (4), p.464-469
• Main Authors: Nozaki, Yuka, Horimoto, Yoshiya, Semba, Ryoko, Ueki, Yuko, Ishizuka, Yumiko, Onagi, Hiroko, Hayashi, Takuo, Kawate, Takahiko, Ishikawa, Takashi, Watanabe, Junichiro
• Format: Article
• Language: English
• ISSN: 2732-7787; 2732-7787
• DOI: 10.21873/cdp.10349

Oncotype DX Breast Recurrence Score test (ODx) is a gene profiling assay predicting the benefit of adjuvant chemotherapy for early-stage hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Meanwhile, to avoid unnecessary financial burden on the patient, many studies have attempted to establish alternatives to ODx using conventional clinicopathological factors, but these have not yet been successful. Thus, we retrospectively investigated clinicopathological factors to establish alternatives to ODx. Data from 114 Japanese women who underwent ODx were retrospectively examined to investigate the relationship between ODx recurrence score (RS) and clinicopathological features, including MUC1 staining patterns on immunohistochemical assessment. An RS of 0-25 was defined as low, and 26-100 as high. Ninety patients (79%) had low RS and 24 patients (21%) had high RS. Univariate analysis revealed that low tumor grade, high progesterone receptor (PgR) expression, and low Ki67 labeling index (LI) were significantly associated with low RS (p=0.025, p