The first is caused by breast hyperplasia; the second is caused by fibroids of the breast; the third is considered to be malignant and needs to be diagnosed by breast ultrasound or mammogram. If the ultrasound of the breast indicates simple breast hyperplasia, the lump is caused by breast hyperplasia. If the ultrasound indicates a hard or tough lump with clear borders, good mobility and intact envelope, it is considered to be a fibroid of the breast. If the lump is hard, with unclear borders, adhesions to the skin and blood flow signals, the possibility of malignancy is highly suspected and further cytological examination is needed.