Five studies reported a relationship between FASN expression and the clinicopathological characteristics of breast cancer patients, including tumor size (large vs. small), histological grade (high vs. low), Tumor Node Metastasis (TNM) stage (high vs. low), lymph node metastasis (yes vs. no), Ki-67 labelling index (high vs. low), estrogen receptor (ER) status (negative vs. positive), progesterone receptor (PR) status (negative vs. positive), and HER2 status (positive vs. negative). This evidence concerns the gene MKI67 and breast cancer.