Postoperative breast cancer, especially after radical mastectomy, has a certain chance of complications. The most common recent complications are subcutaneous fluid accumulation, flap necrosis and incisional dehiscence. Subcutaneous effusion is most often seen 1 week after surgery and is directly due to poor drainage of the subcutaneous drainage tube. There are many reasons for subcutaneous effusion, the most common of which is the failure to tightly electrocoagulate or ligate the lymphatic vessels in the area of ligation, resulting in a large amount of postoperative lymphatic fluid leaking into the subcutaneous area; in addition, fat liquefaction of the flap, excessive early activity, improper placement or blockage of the drainage tube may lead to postoperative subcutaneous effusion. The impact of subcutaneous effusion on patients is relatively small, and few patients complain of serious discomfort due to subcutaneous effusion. The treatment of subcutaneous effusion should be based on the principle of unobstructed drainage, but if the amount of effusion is significantly increased, even after unobstructed drainage and negative pressure suction, it is still difficult to close, and it often requires second-stage surgery to remove fibrotic tissue, thoroughly clean the wound, and place negative pressure drainage. The subcutaneous fluid that appears 72h after surgery is mostly subcutaneous hemorrhage, and the flap can have obvious cyanotic plaques, once it occurs, it will seriously affect the healing of the flap, and the possibility of flap necrosis is significantly higher, attention should be paid to complete hemostasis during surgery, and postoperative drainage should be kept unobstructed. Flap necrosis is also one of the common postoperative complications in the near future. Most of them appear around 2 weeks after surgery, and the early signs are local flap darkening, loss of vitality, and obvious necrosis and detachment starting around 2 weeks. The main causes of flap necrosis are: unskilled application of the electric knife during surgery, long local residence time when freeing the flap, affecting the small blood vessels in the skin, resulting in postoperative skin ischemia and necrosis; improper selection of the incision, postoperative flap not fully freeing to excessive tension; early postoperative subcutaneous accumulation of blood and fluid, affecting the fitting of the flap to the chest wall. After the occurrence of flap necrosis, the flap should be changed daily and the trauma should be carefully observed regularly, and further treatment can be considered when the area of flap necrosis is stable and the boundary with normal tissue is obvious. If the necrotic area of the flap is less than 2 cm2, it can be healed by clearing the wound, changing the medication and applying local burn cream. If the area of necrosis of the flap is not large, the necrotic tissue can be sutured again after active debridement to clear the necrotic tissue. Before implantation, the wound should be actively cleared and changed for 3~4 days to keep the wound clean, with fresh granulation tissue and rich blood supply, which can improve the success rate of implantation. Incisional dehiscence is common within 1 week after suture removal, usually about 2 weeks after radical and modified radical breast cancer surgery, some patients have incisional dehiscence within 1 week after suture removal, and a few still have incisional dehiscence after 2 weeks of suture removal. Generally speaking, excessive flap tension is the main reason for incisional dehiscence. If the width of incisional dehiscence is less than 1 cm, it can usually heal on its own through dressing change; if the width of dehiscence is more than 1 cm, it is estimated that it is difficult to heal on its own, and implantation can be considered to speed up the healing. The selection of incision for radical and modified breast cancer is very important, not only to comply with the principles of surgical oncology, but also to leave enough distance from the edge of the lump, and to consider the tension and blood flow of the flap. Generally speaking, making a transverse shuttle incision can make the flap tension relatively low. The incidence of incisional dehiscence is reduced. In recent years, the authors have tried 3-0 absorbable thread (antibacterial Viejo thread) for continuous suturing of modified radical mastectomy wounds, and the incidence of incisional dehiscence was significantly reduced by not removing the sutures after surgery and waiting for them to fall off on their own. In addition, upper limb dysfunction is a complication that cannot be ignored, mainly in cases of axillary lymph node dissection. It is now generally accepted that the treatment of breast cancer should be a combination of surgery-based treatment. There is a broad consensus on postoperative radiotherapy, endocrine therapy and targeted therapy. However, there are different opinions on the application of preoperative neoadjuvant chemotherapy, but through the above cases, postoperative neoadjuvant chemotherapy can enable more advanced patients to be treated with step-down surgery, enabling breast-conserving surgery to be performed in patients who are not able to undergo breast-conserving surgery, and thus reducing postoperative complications. It has been suggested that preoperative neoadjuvant chemotherapy for breast cancer has a positive impact on the prognosis of breast cancer patients and can improve their prognosis. The data from this study suggest that there should not be any generalization about whether or not neoadjuvant chemotherapy should be given to breast cancer patients. Clinicians should strictly control the indications for neoadjuvant chemotherapy for breast cancer in order to obtain the maximum benefit for patients. For stage I and II patients, whether or not they receive preoperative neoadjuvant chemotherapy has no significant impact on their postoperative survival rate. Some data show that stage II patients who received preoperative neoadjuvant chemotherapy are more likely to have recent related complications after surgery than those who did not receive neoadjuvant chemotherapy at the same stage. Therefore, it is debatable whether stage I and II breast cancer patients must receive neoadjuvant chemotherapy before surgery. For patients with advanced stages, preoperative neoadjuvant chemotherapy can significantly improve the survival rate at 3 and 5 years after surgery. For patients with stage III breast cancer, neoadjuvant chemotherapy can improve the prognosis of patients, and the benefits clearly outweigh the disadvantages. Its use in this group of patients should be advocated.