In general, the vast majority of mastocytosis grade 4 is not a serious clinical condition, but further pathological examination is usually required to rule out the possibility of malignancy. Because mastocytosis is a benign disease of the breast, its pathogenesis is mainly related to the body’s estrogen and progesterone, as well as the imbalance of lactogen. The typical clinical manifestation is the appearance of breast lumps, breast swelling and pain at the onset of menstruation, and the symptoms can be relieved or disappear after the menstruation. Although the probability of malignancy in grade 4A is usually within 5%, further puncture pathology biopsy is usually required to exclude the possibility of malignancy. If it is confirmed to be malignant, radical or modified radical treatment of breast cancer needs to be incorporated, together with post-operative chemotherapy, radiotherapy, and even molecular targeted drugs as a comprehensive treatment, thus improving the cure rate of breast cancer. Since mammary hyperplasia appears as a grade 4A lump, the probability of malignant transformation is generally very low, so it is not a very serious disease, but one needs to be alert to malignant transformation.