Microwave Ablation in the Treatment of Early-stage Unifocal Invasive Breast Cancer

Inclusion Criteria: 1. female patients aged 18-70 years; 2. patients with newly diagnosed invasive breast cancer confirmed by core needle biopsy; 3. the tumor smaller than 2cm in greatest diameter confirmed by US (ultrasonography), breast X-ray and breast MRI (contrast-enhanced magnetic resonance image ) were performed at the same time, and the difference of the largest diameter between breast US and MRI was less than 0.5 cm; 4. the single tumor without other suspicious lesions (BI-RADS (the Breast Imaging Recording and Data System) score ≥4) evaluated by breast US, X-ray and MRI; 5. the tumor without adhesion to chest wall, nipple or skin; 6. patients without distant metastasis; 7. Karnofsky performance status greater than 70%. Exclusion Criteria: 1. multicentric or multifocal breast tumor; 2. the tumor located on nipple and areola area; 3. signs of extensive intraductal carcinoma on imaging examination (diffuse malignant calcification on breast X-ray or segmental distribution, non-mass enhancement, ductal or linear enhancement \> 2.5 cm on MRI); 4. extensive intraductal component in invasive cancer (more than 50% of the tumor volume) confirmed by pathology; 5. invasive lobular carcinoma, metaplastic carcinoma or carcinoma with sclerosing adenosis; 6. patients who were pregnant or breastfeeding; 7. patients with evidence of coagulopathy, chronic liver diseases or renal failure; 8. patients with previous treatment including chemotherapy, targeted drug therapy, or local radiation therapy, etc; 9. patients with substance abuse, or mental or psychological disorders that may interfere with study compliance; 10. any condition that is unstable or likely to compromise the patient's safety and compliance; 11. patients enrolled in other clinical trials; 12. diseases or symptoms that other investigators consider unsuitable for participation.