Clinical Efficacy and Safety Assessment of Breast-Conserving Surgery for Central Breast Cancer: A Prospective Randomized Controlled Trial

This study enrolled 158 patients with primary central early-stage breast cancer and randomly assigned them to two groups. The control group underwent total mastectomy (with optional prosthetic implantation or autologous tissue reconstruction), while the experimental group received breast-conserving surgery combined with radiotherapy (nipple resection with concurrent nipple reconstruction and oncoplastic surgery when nipple involvement was present; conversion to total mastectomy required for intraoperative or postoperative positive margins). The primary endpoint was local recurrence rate, with secondary endpoints including disease-free survival (DFS), overall survival (OS), patient-reported outcomes (PRO), and surgery-related complications.

This prospective, open-label, multicenter, randomized clinical trial plans to enroll 158 patients with primary central early-stage breast cancer. Participants will be randomly assigned to two groups: the control group undergoing total mastectomy (with optional prosthetic implantation or autologous tissue reconstruction), and the experimental group receiving breast-conserving surgery with radiotherapy (nipple resection with concurrent nipple reconstruction and oncoplastic surgery when nipple involvement is present; conversion to total mastectomy required for intraoperative or postoperative positive margins). All enrolled patients will initiate surgical treatment within 24 hours after eligibility confirmation. Experimental group patients must complete preoperative breast ultrasound, mammography, and MRI to assess breast-conserving feasibility. All patients receive standardized adjuvant therapy (chemotherapy, endocrine therapy, targeted therapy, and immunotherapy) according to guidelines. Those meeting neoadjuvant therapy criteria may receive preoperative systemic treatments (chemotherapy, endocrine therapy, targeted therapy, and immunotherapy), excluding neoadjuvant radiotherapy.

Primary Endpoint:

local recurrence rate

Secondary Endpoints:

disease-free survival (DFS), overall survival (OS), patient-reported outcomes (PRO), and surgery-related complications.

Inclusion Criteria:

1. Female patients aged 18-70 years with primary breast cancer;
2. Histopathologically confirmed invasive breast cancer (meeting latest ASCO/CAP guidelines criteria) with:

   * TNM stage T1-2;
   * Nodal stage N0-1;
3. Ductal carcinoma in situ (DCIS) with maximum tumor diameter \<3 cm;
4. Paget's disease;
5. Neoadjuvant chemotherapy permitted for eligible patients;
6. Unicentric lesion confirmed by breast ultrasound, mammography, and MRI;
7. Nipple-areolar complex resection required for preoperative imaging or pathologically confirmed nipple involvement;
8. Enrolled patients randomized 1:1 to breast-conserving surgery or total mastectomy group;
9. Participants voluntarily signed informed consent forms and completed ethics review procedures.

Eligibility Criteria:
Inclusion Criteria:

1. Female patients aged 18-70 years with primary breast cancer;
2. Histopathologically confirmed invasive breast cancer (meeting latest ASCO/CAP guidelines criteria) with:

   * TNM stage T1-2;
   * Nodal stage N0-1;
3. Ductal carcinoma in situ (DCIS) with maximum tumor diameter \<3 cm;
4. Paget's disease;
5. Neoadjuvant chemotherapy permitted for eligible patients;
6. Unicentric lesion confirmed by breast ultrasound, mammography, and MRI;
7. Nipple-areolar complex resection required for preoperative imaging or pathologically confirmed nipple involvement;
8. Enrolled patients randomized 1:1 to breast-conserving surgery or total mastectomy group;
9. Participants voluntarily signed informed consent forms and completed ethics review procedures.

Exclusion Criteria:

1. Tumor-related characteristics

   1. Metastatic or bilateral breast cancer
   2. Inflammatory breast cancer
   3. Multicentric lesions
2. Comorbidities/treatment history

   1. History of other malignancies (except cured cervical carcinoma in situ/basal cell carcinoma/squamous cell carcinoma) or prior anticancer therapy (systemic/local)
   2. Major non-breast surgery within 4 weeks before enrollment (excluding diagnostic biopsy/PICC placement) without full recovery
   3. Active infections/immune disorders:

      HIV/AIDS Viral hepatitis (HBV-DNA≥500 IU/ml; HCV antibody-positive with detectable HCV-RNA) Autoimmune hepatitis HBV/HCV coinfection
   4. Allogeneic bone marrow/solid organ transplantation history or planned
   5. Cardiovascular diseases:

      * Heart failure or LVEF\<50%
      * Uncontrolled arrhythmias (resting heart rate\>100 bpm, ventricular tachycardia, Mobitz II/third-degree AV block)
      * Angina requiring antianginal drugs
      * Clinically significant valvulopathy
      * Transmural myocardial infarction on ECG
      * Uncontrolled hypertension (SBP\>180 mmHg and/or DBP\>100 mmHg)
3. Reproductive status

   Pregnancy/lactation, or reproductive-aged women with:
   * Positive baseline pregnancy test
   * Refusal of effective contraception
4. Neuropsychiatric disorders Epilepsy, dementia, psychoactive substance abuse, or alcoholism
5. Other investigator-determined exclusionary conditions