The mean minimum ADC value for HER2-low breast cancer was (0.99 ± 0.21) × 10−3 mm2/s, significantly lower than that for HER2-negative breast cancer ((1.1 ± 0.2) × 10−3 mm2/s) (FDR-adjusted p-value = 0.01). This evidence concerns the gene ERBB2 and breast carcinoma.