They observed that among 218 samples with RS 0–25, 54 (25%) had Ki-67 ≥20%, and among 80 samples with RS 26–100, 23 (29%) had Ki-67 <20%, revealing a moderately positive correlation between the Oncotype DX breast cancer RS and Ki-67 by immunohistochemistry. Here, MKI67 is linked to breast cancer.