Breast carcinoma in situ generally does not need targeted therapy. Breast carcinoma in situ is in fact intraepithelial cancer, the cancer cells only exist in the epithelial layer and do not invade the basement membrane, that is to say, they do not invade other mesenchymal and dermal tissues, and there is no metastasis to lymph nodes or distant organs, so radical surgical excision is the main method, and there is no need to carry out other treatments. Most of the patients with carcinoma in situ can be completely eliminated through surgery, and they can recover without radiotherapy, chemotherapy and targeted therapy, but they need to follow the doctor’s instructions for regular checkups after surgery. Patients diagnosed with carcinoma in situ should go to the hospital for timely consultation and early treatment to achieve better therapeutic effect.