Surgical operation is the main surgery for treating rectal cancer. With the improvement of people's understanding of the anatomy and pathology of rectal cancer, the improvement of surgical skills and methods, the development of instrument equipment, as well as the change of people's concept and the improvement of the requirement for surgery, the extensive application of comprehensive treatment has enriched the content of rectal cancer surgery, and the overall efficacy has also improved. Especially in the past 20 years, there has been rapid development and progress. First, "the change of 'concept' and 'goal' is the driving force for the development of surgery". People have changed from a single pursuit of the goal of "eradicating cancer and saving lives" to the dual standard of "eradicating cancer and improving quality of life". The abdominoperineal resection has become the last choice from the "golden standard", making anal preservation surgery the preferred option. In order to better preserve the anus, low anterior resection with double staplers, colonic pull-through resection, colonic pouch-anal anastomosis, local excision, etc. have all developed. To ensure the reasonable selection of anal surgery, people pay attention to the correct preoperative assessment, especially the correct assessment of the disease stage is an important basis for choosing the surgical method. Digital rectal examination, endorectal ultrasound and pelvic CT are three main means to provide disease stage information. Through comprehensive and correct preoperative evaluation, treatment policy and surgical method are determined. For rectal cancer patients, avoiding permanent abdominal colostomy and preserving健全control function is the first consideration in improving postoperative quality of life. Therefore, under the premise of ensuring radical cure of cancer, improving the success rate of anal preservation surgery is a standard for measuring the level of surgeons. This includes two requirements: one is sound defecation control function, ultimately having normal anal-rectal function; the other is to minimize local recurrence rate and improve 5-year survival rate. According to these two requirements, the emergence and development of colonic pouch-anal anastomosis reflects people's exploration of the slow recovery and establishment of fecal storage function after rectal resection while preserving sphincter function. With the rationality and gradual maturity of this surgery, it has been widely adopted abroad at present and has become the preferred surgical method in anal-preserving surgery. On the other hand, since Heald et al. proposed that the principle of "total mesorectal excision" can reduce the local recurrence rate after surgery, a large amount of clinical research data has confirmed the correctness of this view, and it has quickly been accepted as the operating principle that should be followed during radical resection of the rectum. The application of total mesorectal excision provides specific guarantees for the radical cure of cancer in anal-preserving surgery. It can be considered that colonic pouch-anal anastomosis and total mesorectal excision are the two most outstanding achievements in the surgery of rectal cancer in the past 20 years. But people are not satisfied with these achievements. In improving quality of life, after preserving the anus and obtaining sound defecation control function, the incidence of postoperative bladder dysfunction in patients has significantly decreased. In addition, some scholars continue to explore whether lateral lymph node dissection has value in the surgical treatment of rectal cancer. Measured by the above two standards, although lateral lymph node dissection causes more damage to postoperative quality of life, the reduction in local recurrence rate and the improvement in survival rate are relatively mild. For this reason, it is proposed that when performing lateral lymph node involvement, preserving autonomic nerves will significantly affect postoperative life, so it is inappropriate to perform autonomic nerve preservation at this time. In general, the impression of expanded resection surgery is "limited benefits, too much cost, somewhat uneconomical", so it has never been adopted by Western scholars. For patients who cannot undergo anal-preserving surgery even if they try, how to improve their postoperative defecation ability remains the most striking issue in improving quality of life. For this purpose, people attempt various sphincter reconstruction surgeries, such as gracilis muscleplasty, gluteus maximus muscleplasty, in-situ anusplasty, and electronic anus installation, to improve the quality of life of patients undergoing colostomy after surgery. Undoubtedly, the starting point is good, benefiting some patients, but it is still different from a normal anus, and the results are not entirely ideal. However, this reflects people's concern about improving postoperative quality of life and their efforts towards it. For mid-to-late stage lesions, in order to reduce local recurrence rate and improve survival rate, people tend to adopt comprehensive treatment. Auxiliary radiotherapy was previously believed to help reduce local recurrence rate. By marking suspicious residual or incompletely removed areas through surgery for postoperative radiotherapy, the targeting might be stronger and the effect better. However, postoperative radiotherapy has certain disadvantages: (1) Postoperative local tissues experience fibrosis, scarring reactions, ischemia, and reduced oxygen levels, which affects the effectiveness of radiotherapy; (2) Normal intestinal segments receiving radiotherapy increase the incidence of radiation enteritis and anastomotic stenosis; (3) Small intestine falling into the pelvis after radiation exposure is more likely to develop radiation-induced small bowel enteritis, intestinal adhesions, obstruction, and even perineal small bowel fistulas. Therefore, there is now a tendency towards preoperative radiotherapy because it has the following advantages: (1) Local tissue oxygen supply is good, increasing sensitivity to radiation; (2) Tumor shrinkage and downstaging can increase the rate of anal-preserving surgery; (3) The incidence of radiation-induced proctitis and intestinal adhesions and obstructions significantly decreases. A large number of clinical studies have confirmed that preoperative radiotherapy reduces local recurrence rates and improves 5-year survival rates. If preoperative radiotherapy is combined with chemotherapy, it can increase the downstaging ratio and treat micro-metastases from the start. Preoperative radiotherapy makes surgical operations easier, increases the anal preservation rate, reduces local recurrence rates, and keeps local recurrence rates below 5% within a median follow-up period of 2-3 years. This comprehensive treatment is developing and becoming a new trend. It not only significantly improves the therapeutic effects on patients with resectable mid-to-late stage lesions but also becomes a treatment method to change the fate of patients with progressive, recurrent, and metastatic lesions. Long-term, the appearance or existence of recurrence and metastasis means that the patient has entered the late stage - Stage IV. Therefore, most doctors can only offer symptomatic treatment to patients, feeling helpless, and even advise patients to eat well and relax during the limited time left, and go out to play or see things if physically permitted. However, the emergence and reasonable application of comprehensive treatment can completely change this passive waiting into active treatment. Although simple radiotherapy for local recurrence can temporarily relieve symptoms in 50-90% of cases, the locally recurrent lesion often progresses within five months after radiotherapy, leading to death within two years after recurrence diagnosis. Aggressive secondary surgery leads to a high recurrence rate of up to 77%. The recurrence rate after radiotherapy plus surgery remains at 40%. Recent reports show that using preoperative chemoradiotherapy + surgery + postoperative therapy or preoperative chemoradiotherapy + surgery + intraoperative radiotherapy + postoperative chemotherapy can transform most originally unresectable lesions into resectable ones, with more than 50% achieving radical resection. The 3-year survival rate of resected cases reaches 82%, and the 3-year survival rate of unresectable cases is 38%, showing that comprehensive treatment improves the survival rate and survival time of recurrent cases. These results are encouraging and hopeful. In liver metastasis cases, adopting a strategy of systemic chemotherapy plus regional chemotherapy plus aggressive surgery can make 16% of originally unresectable cases become resectable, and the 5-year survival rate after surgery reaches 40%, which is the same as the efficacy of primary liver resection. It seems that when people take an active attitude to implement comprehensive treatment, some patients originally considered incurable in the late stage improve their quality of life and even achieve long-term survival. Facing these clinical realities, people realize that an active attitude should be taken to explore reasonable and better comprehensive treatment plans. For cases where local extensive infiltration or peritoneal dissemination cannot be surgically resected, the quality of life and survival period of patients can be improved through methods such as regional arterial perfusion chemotherapy and intraperitoneal hyperthermic chemotherapy. In summary, comprehensive treatment has become an important means and research hotspot in current cancer treatment. People recognize the limitations of surgical knives and need new treatment methods to enrich existing comprehensive treatment contents to improve efficacy. Since the first successful laparoscopic cholecystectomy in the 1980s, surgery has entered the "laparoscopic era". With the development of 3D imaging technology and the improvement of the ability to display abdominal cavity anatomy through monitors, laparoscopic surgery has become much easier. Therefore, in the past decade, there has been significant development in new auxiliary instruments and equipment. Various abdominal surgeries can be explored and operated through CO2 pneumoperitoneum, and electrocoagulation can be safely used. Laparoscopic colorectal surgery appeared in the early 1990s, and there are two types of this surgery: complete laparoscopic surgery and laparoscopic-assisted surgery. Since laparoscopic surgery cannot palpate colon lesions, it may be difficult to locate the primary tumor, and the possibility of missing synchronous colon tumors may increase. To avoid this situation, it is recommended to mark the diseased part of the colon wall during preoperative colonoscopy or perform intraoperative colonoscopy localization. Undoubtedly, laparoscopic surgery has many advantages, including less trauma, less pain, faster bowel function recovery, shorter hospital stay, faster postoperative rehabilitation, short-term efficacy similar to traditional surgery, and possibly protective effects on immune function, etc. Its use for benign colon lesions currently does not raise much controversy, but its use for cancer treatment has significant differences, and the biggest difference is the possibility of tumor cell implantation at puncture sites (trocar sites) or window sites (port sites). There are several reasons for implantation at puncture sites: (1) Tumor cells escape during operation; (2) Tumor cell dissemination during CO2 pneumoperitoneum; (3) Rupture of the peritoneum; (4) Hematoma at puncture sites becomes a trap for tumor cells; (5) Tumor cells escape when specimens are removed. The incidence of recurrence at window sites varies greatly and has the characteristics of a "learning curve." Existing data shows no difference between laparoscopic surgery and open surgery in terms of length of bowel segment resection and number of lymph nodes cleared. Although there have been many good results reported, whether the recurrence rate of laparoscopic surgery is the same as open surgery needs to wait for the results of ongoing prospective randomized studies by NCI and COST. Recently, a prospective randomized study compared 42 cases of laparoscopic surgery with 38 cases of regular open surgery, with median follow-up times of 1.5 and 1.7 years respectively. There was no recurrence at window sites, and cancer-related deaths were equal in both groups. The recent results are good, but these authors correctly pointed out that the results of a single unit differ from those of multiple units, lacking statistical power, especially regarding recurrence at window sites, because some reports estimate the incidence at 1% to 1.5%, thus requiring a large number of cases to fully assess whether laparoscopic surgery increases tumor implantation. Franklin et al. reported a non-randomized, prospective multi-center study involving 194 cases of colorectal cancer undergoing either laparoscopic or open surgery, with an average follow-up of 22 months. The number of removed lymph nodes, margin length, survival rate, and disease-free interval were all similar. The recurrence rate for open surgery was 7%, and for laparoscopic resection was 8%. Lacey et al. reported a Spanish randomized study showing that laparoscopic surgery and open resection were safe for removing lymph nodes in both benign and malignant intestinal lesions, with short-term efficacy comparable to open surgery. Small colon cancers can be removed via laparoscopic surgery, whereas giant or advanced cancers are preferably treated with open surgery.