Young breast cancer is less common in Western countries but accounts for a higher percentage of breast cancers in our country. The definition of young is generally defined as being under 30, 35 or 40 years of age, but most people define under 35 years of age as young. The biological behavior and risk of recurrence of breast cancer in young breast cancer patients are different from those of older patients, which leads to different treatment strategies for these two groups. Younger breast cancers have the following clinicopathological and biological characteristics: 1. more advanced stage: even if the stage is the same, their prognosis is worse, which is the result of a different biological behavior. 2. More likely to have bone marrow micrometastases. 3.Most of them are invasive carcinoma: about 70% are invasive ductal carcinoma. 4.High malignancy of tumor cells: Most of them are accompanied by vascular cancer thrombus, extensive intraductal cancer component, Her-2 overexpression (positive rate 26%-44%), ER negative (negative rate 39%-80%), high percentage of S stage cells and P53 and Ki-67 overexpression. 5. Basal-like breast cancer or triple negative breast cancer: 34% of breast cancers under 30 years of age are basal-like breast cancer, while the overall incidence of basal-like breast cancer is 14%-16%. Treatment strategies 1. Surgery It is generally believed that younger patients undergoing breast-conserving surgery (BCT) have a higher rate of local recurrence (LR) than older patients. However, there is controversy regarding the effect of age on local recurrence. There is evidence that improvements in treatment may reduce LR rates in younger patients who undergo BCT. One study showed LR rates of 50%, 33.3%, and 20.8% in patients under 35 years of age with positive, indeterminate, and negative cut margins, respectively. This strongly suggests the need for more caution in managing the cut margin status of young breast cancers. There is no evidence yet that the overall survival (OS) rate is reduced in younger patients who undergo BCT. Definitive findings on the effect of age on LR after radical surgery are still lacking. Negative cut margins, application of local addition of radiotherapy and adjuvant systemic therapy all reduce the risk of LR in young patients after BCT. Therefore, young patients are not a contraindication to BCT. 2. Internal therapy Adjuvant chemotherapy is effective in reducing the risk of recurrence in <50 years. This is partly due to the high proportion of ER-negative patients in younger patients. Younger patients receiving preoperative chemotherapy can reduce staging and make them more suitable for BCT, but there are no reports of improved survival with neoadjuvant chemotherapy. Oral TAM for 5 years is the standard of care for premenopausal hormone receptor-positive early breast cancer. Aromatase inhibitors are not indicated for the treatment of premenopausal breast cancer. Ovarian debulking may also be an effective treatment. Methods of debulking include oophorectomy, radiotherapy and pharmacological debulking (luteinizing hormone-releasing hormone analogs). A meta-analysis confirmed that those <50 years old can benefit from ovarian denervation alone. Ovarian denervation ± TAM, has similar efficacy to CMF chemotherapy regimens, and the St. Gallen consensus suggests that ovarian denervation combined with TAM may be used as adjuvant therapy for some premenopausal individuals with a moderate risk of recurrence. One study showed that CAF chemotherapy regimen + goserelin significantly improved the prognosis compared to CAF + TAM + goserelin (5-year RFS of 78% and 67%, respectively).