NOTCH1 and cancer: The mean percentage of NOTCH1-positive expression was 18.8% (standard deviation (SD) = 40.3%) in normal histology, 41.2% (SD = 50.7%) in malignant tumors, 44.6% (SD = 49.8%) in precancerous tumors, and 47.7% (SD = 50.2%) in benign tumors.