1. A method of microcalcification detection in mammographic images, comprising: forming a plurality of true microcalcification (mcc) clusters from a plurality of cancerous mammographic images that pass an mcc ground truth measure test; forming a plurality of normal clusters from a plurality of normal mammographic images; gathering spot and cluster features from said true mcc clusters and normal clusters; extracting linear structure features in said cancerous mammographic images and normal mammographic images guided by said true mcc clusters and said normal clusters using said gathered spot and cluster features and said extracted linear structure features in mcc detector training; and applying said mcc detector to mammographic test images which are under testing for cancerous lesions.