Breast Cancer Staging and Surgical Options Breast cancer is a disease that seriously affects women’s life expectancy and quality of life, and its incidence is increasing year by year. 514,000 new cases of breast cancer occurred worldwide in 1975, and 209,060 new cases and 40,230 deaths were expected in the United States in 2010. The incidence of breast cancer in China has also increased rapidly in recent years, so the prevention and treatment of breast cancer is of great importance. The surgical treatment of breast cancer occupies an important position, and the following is a review of the surgical options for different stages of breast cancer. In 1894, Halsted first performed radical surgery for breast cancer, i.e., removal of the breast, pectoralis major and minor muscles and clearance of axillary lymph nodes. Halsted’s theory was that tumor cells metastasized regularly from the breast to the lymph nodes, and therefore, radical breast surgery maintained its dominance as the first choice of surgical treatment for breast cancer at that time. 75 years, and breast surgery entered a phase of maximum tolerable treatment. Later, despite continued research in adjuvant breast cancer treatment, the trend toward expanded surgical treatment continued. 1952 Carey and Kirlin first reported expanded radical surgery for breast cancer, in which internal breast lymph node removal was performed in addition to radical surgery. Fisher’s theory was decisive for the development of breast surgery. Fisher believed that breast cancer is a systemic disease, the metastasis of tumor cells is not orderly, blood flow dissemination plays a very important role in the process of tumor metastasis, and changes in local regional treatment have less impact on survival. in 1963, Auchincloss, on the basis of radical surgery The pectoralis major and pectoralis minor muscles were preserved, and this is the modified radical surgery for breast cancer that has been used to this day. The resection of the pectoralis major and pectoralis minor muscles has a greater impact on the quality of life of patients, and the expansion of the surgical scope does not significantly improve the survival of patients. However, some of these patients can undergo tumor downstaging by neoadjuvant chemotherapy before surgery and subsequently undergo modified radical surgery, which can also ensure a higher survival rate. For patients with less extensive invasion of the pectoral muscle, only the involved muscle bundle can be removed and additional chest wall radiotherapy can be given postoperatively as an alternative to radical surgery. However, recurrence of internal breast lymph nodes is rare, and most authors do not recommend internal breast lymph node dissection or radiotherapy as routine treatment. Romestaing reported that there was no statistical difference in overall survival between patients who received and did not receive internal breast lymph node radiation therapy. Therefore, the use of extended radical surgery that includes lymph node dissection in the internal breast area is even more limited. Modified radical surgery is primarily indicated for the majority of breast cancer patients whose tumors do not involve the pectoral muscle. Since this procedure is easy to master, the trauma to the patient is still within the acceptable range, and it is in line with the national conditions of China, it is a popular procedure in China at present. However, modified radical surgery is no longer in line with the development direction of breast surgery abroad and is gradually replaced by breast-conserving surgery and axillary sentinel lymph node biopsy. The NSABP B-06 study confirmed that the long-term survival rate of patients who received breast-conserving treatment and mastectomy was similar. As an important part of breast-conserving treatment, breast-conserving surgery has become the standard procedure for the surgical treatment of breast cancer. Breast-conserving treatment is generally suitable for breast cancer patients with clinical stage I or II patients whose maximum tumor diameter does not exceed 3 cm, while the breast needs to have appropriate volume and be able to maintain the cosmetic outcome after surgery. Patients who have received prior radiation therapy to the affected breast or chest wall, pregnant patients, patients with diffuse malignant calcifications on mammography, patients with extensive lesions that cannot be resected with a single enlarged incision to achieve negative margins, patients with positive margins after enlarged resection and negative margins cannot be guaranteed after re-excision, patients with active connective tissue disease, patients with tumors larger than 5 cm in diameter (but it is recommended to measure the tumor as a percentage of the breast) However, those with tumor diameter of 3~5cm and willing to conserve breast can be treated with neoadjuvant chemotherapy and breast-conserving treatment can be considered after tumor shrinkage; those with tumor larger than 5cm and tumor shrinkage to less than 3cm after neoadjuvant chemotherapy can also be carefully considered), and those with tumor located in the central region of the breast are contraindicated for breast-conserving surgery. It has been shown that young patients under the age of 35 have a relatively high risk of recurrence and reoccurrence of breast cancer, so when choosing breast-conserving surgery, the surgeon should fully explain the possible risks to the patient. The margins of breast-conserving surgery are critical. Most North American radiologists consider a negative margin (tumor not exceeding the stained surface of the resected specimen) to be sufficient, while surgeons and European radiologists prefer a margin distance of 2 to 5 mm. Those with invasive cancer components found at the margin are at increased risk of ipsilateral breast recurrence and should undergo a second extended excision. The greater margin distance required for intraductal carcinoma may reflect the tendency of intraductal carcinoma to spread intermittently. The presence of lobular carcinoma at the margin is not an indication for re-expansion. The most important advantage of neoadjuvant chemotherapy is the opportunity to convert patients with initially large tumors requiring mastectomy to breast-conserving surgery. The NSABP B18 study showed that after 4 cycles of neoadjuvant chemotherapy, 36% of patients achieved complete clinical remission and were 8% more likely to undergo breast-conserving surgery; after 9 years of follow-up, the ipsilateral breast recurrence rate was slightly higher in those who underwent breast-conserving surgery after neoadjuvant chemotherapy than in those who underwent mastectomy. However, the difference was not statistically significant. Therefore, breast-conserving surgery after neoadjuvant chemotherapy is also a reasonable treatment modality. However, the appropriate selection criteria for breast-conserving surgery after neoadjuvant chemotherapy for breast cancer patients is the key to reduce ipsilateral breast recurrence, and it is generally believed that breast-conserving surgery after neoadjuvant should also follow the above-mentioned criteria. 3. Skin-preserving mastectomy, nipple-areola complex-preserving mastectomy and breast reconstruction surgery Since not all breast cancer patients can receive breast-conserving surgery, for quite a long time, most patients who are not suitable for breast-conserving treatment have to undergo traditional mastectomy. With the increasing involvement of oncoplastic techniques in the surgical management of breast cancer, skin-preserving mastectomy (SSM) and nipple-areola complex-preserving mastectomy (NSM) have emerged. SSM can lead to a dramatic improvement in the cosmetic outcome after immediate breast reconstruction, and evidence shows that skin-preserving mastectomy does not increase the risk of local recurrence compared to conventional mastectomy risk. Some studies have shown that although the percentage of tumor invasion of the nipple-areola complex is low and local recurrence still occurs in a small percentage of patients in short-term follow-up, there is a lack of data on long-term follow-up; at the same time, there is a high rate of nipple-areola complex necrosis after preservation of the nipple-areola complex, and there is a lack of good studies reporting quality-of-life data such as nipple sensation and self-satisfaction with breast appearance, and this procedure should be performed with caution. The indications for SSM and NSM include extensive DIN grades 1, 2, and 3, multifocal, multicentric carcinoma, and no history of breast radiotherapy, while the indications for NSM must include no clinical nipple involvement and negative intraoperative frozen pathology of the postareolar tissue. malignant calcifications originating from the nipple-areola complex, and positive margins of the nipple-areola complex. Depending on the timing of the reconstruction, breast reconstruction can be divided into stage I reconstruction and stage II reconstruction. Stage I breast reconstruction can be performed at the same time as SSM and NSM. The timing of breast reconstruction depends on many factors, and the best timing can only be determined by fully considering the advantages and disadvantages of both reconstructive procedures, as well as many of the patient’s own factors. Depending on the material used for reconstruction, breast reconstruction can be divided into autologous tissue reconstruction and implant reconstruction. Implants can be placed either under the pectoralis major muscle or within the subcutaneous fatty tissue. Commonly used implants include saline capsules, silicone implants, and hybrid saline capsules with silicone shells. The most commonly used autologous tissue flaps include the extended latissimus dorsi muscle flap, the transverse tipped rectus abdominis muscle flap (TRAM), the free transverse rectus abdominis muscle flap (F-TRAM), the free TRAM with preserved muscle bundle (MS-FTRAM), the inferior abdominal wall vascular perforator flap (DIEP), and the superior gluteal artery perforator flap (SGAP), etc. For patients who need to receive adjuvant radiotherapy, it is necessary for the surgeon and the radiotherapist to fully coordinate the timing of the patient’s breast reconstruction preoperatively in order to balance the surgical, radiotherapy and cosmetic outcomes. 4.Sentinel lymph node biopsy As a minimally invasive biopsy technique for accurate staging of the axilla, sentinel lymph node biopsy (SLNB) represents the highest level of development in the surgical treatment of breast cancer, with evidence-based medical level I/II evidence confirming that SLN-negative patients can be exempted from axillary lymph node dissection (ALND), that SLNB can accurately determine the status of axillary lymph nodes, that complications of SLNB instead of ALND Significantly fewer complications, and a lower rate of axillary recurrence with SLNB instead of ALND in SLN-negative patients. In addition, the safety of SLNB radiation has been confirmed, and the operation of SLNB is becoming more standardized. SLNB is the standard of care for early invasive breast cancer.