Omission of SLNB in CN0 Early Breast Cancer

Inclusion criteria

• Female patients aged 18-70 years;
• Pathologically confirmed invasive breast cancer (regardless of pathological type) with a tumor diameter ≤ 3 cm, and planning to undergo breast surgery;
• Negative axillary lymph nodes assessed by physical examination and imaging (2 or more of the following tests including ultrasound, breast MRI, breast PET-CT, breast PET-MRI, breast PET);
• All patients are required to undergo immunohistochemical staining for Estrogen Receptor (ER), Progesterone Receptor (PR), human epidermal growth factor receptor 2 (HER2), Ki-67 proliferation index, and further fluorescence in situ hybridization (FISH) should be performed in HER2 2+ cases;
• Good compliance, normal comprehension and ability to receive treatment and follow-up as required;
• ECOG score 0-1;
• Patients volunteered for this study and signed the informed consent form.

Exclusion criteria

• Bilateral/lactating/pregnant breast cancer;
• Previous history of malignant tumor or neoplasm;
• Clinical or imaging confirmation of distant metastasis;
• History of previous surgery on the affected axilla; or history of surgery affecting the function of the upper extremity;
• Prior history of radiotherapy to the breast or chest;
• Positive pathological margins after breast-conserving surgery or mastectomy;
• Severe coagulation disorder, or a serious systemic disease, or an uncontrollable infection;
• Aspartate aminortransferse (AST) and Alanine aminotransferase (ALT) ≥ 1.5 times the upper limit of normal, alkaline phosphatase ≥ 2.5 times the upper limit of normal, total bilirubin ≥ 1.5 times the upper limit of normal, serum creatinine ≥ 1.5 times the upper limit of normal; left ventricular injection fraction (LVEF) < 50% on cardiac ultrasound;
• Inability to complete the full course of follow-up adjuvant therapy as prescribed by the doctor for various reasons;
• No personal freedom and independent civil capacity;
• Presence of mental disorders, addictions, etc;
• Not eligible for enrollmentas as judged by the investigator.