When you see this title, many of you may ask, “Isn’t the surgery we usually do already laparoscopic, and what is this “fully laparoscopic surgery”? At the beginning of the 21st century, with the release of the results of several large-scale multicenter randomized controlled clinical studies, the field of colorectal surgery entered the minimally invasive era represented by laparoscopic surgery. Unlike the results of recent clinical studies on minimally invasive surgery for gynecologic tumors published in the New England Journal of Medicine, the CLASICC study, the COLORI study, the COLORII study, the COST study, and the COREAN study for Asian populations published in the New England Journal of Medicine, The Lancet, and other prestigious journals more than a decade ago have shown that laparoscopic surgery for colorectal cancer not only has the advantage of being less invasive than laparoscopic surgery, but also has the advantage of being less invasive than laparoscopic surgery for colorectal cancer. Laparoscopic surgery for colorectal cancer not only has long-term outcomes including 5-year survival rates that are comparable to those of traditional open surgery, but also has significantly better near-term outcomes in terms of less pain, shorter time to return to defecation, and faster discharge from the hospital. Therefore, for colorectal tumor surgeons, the surgical option to consider is not whether to choose traditional open surgery or minimally invasive laparoscopic surgery, but whether to further reduce the damage to patients based on conventional laparoscopic surgery, to ensure the effect of tumor eradication while making patients recover faster, and whether to achieve the “minimally invasive of minimally invasive” treatment. Although 90% of colorectal cancer patients in large medical institutions have undergone laparoscopic surgery, strictly speaking, it is called “laparoscopic assisted radical colon cancer surgery”. For colon cancer, laparoscopic surgery includes two categories, one is the “laparoscopic-assisted surgery” that is routinely used in clinical practice, while the other is the “fully laparoscopic surgery” that requires higher surgical operation techniques and skills. Laparoscopic-assisted surgery, as the name suggests, means that laparoscopic equipment is used to assist the operator in completing the surgery, while “fully laparoscopic surgery” means that all steps of the surgery are performed under the laparoscope. The operation of colon cancer mainly consists of the following steps: removal of the lymph nodes at the root of the mesentery, dissection of the main blood vessels that govern the blood supply to the intestinal segment, freeing of the diseased intestinal segment, cutting of the mesentery at both ends of the tumor, resection of the diseased intestinal segment and reconstruction of the digestive tract. For “laparoscopic-assisted surgery”, as long as one or more of the above steps are completed laparoscopically, resulting in a shorter final surgical incision and less damage to the patient, it can be called “laparoscopic surgery”. For colorectal surgeons who are new to laparoscopic surgery, “laparoscopic-assisted surgery” may simply involve laparoscopic freeing of the intestinal canal at the tumor site, followed by making an appropriate incision in the abdomen to complete lymph node dissection and vascular dissection, and finally lifting the intestinal segment to be resected outside the abdominal wall incision to complete the operation by cutting the mesentery, resecting the intestinal segment and reconstructing the digestive tract. For more skilled laparoscopic surgeons, more surgical operations can be performed laparoscopically, in which case “laparoscopic-assisted surgery” can be performed not only by freeing the intestine but also by clearing the lymph nodes and dissecting the blood vessels, and then by making a small incision in the abdomen, lifting the intestinal segment outside the abdominal wall incision, completing the trimming of the mesentery, resection of the intestinal segment and reconstruction of the digestive tract, and finally The surgery is completed. The more surgical steps completed under laparoscopy, the fewer surgical operations need to be done outside the abdominal cavity, the smaller the abdominal wall incision required, and the shorter the time the abdominal cavity is exposed to air, which results in less damage to the patient and faster postoperative recovery. Most of the laparoscopic surgeries for colon cancer in clinical practice also belong to this type of “laparoscopic-assisted surgery”. Then, can we further reduce the surgical incision on the basis of the current minimally invasive surgery, further reduce the damage of surgery and make the patient recover faster? If we perform all steps of radical colon cancer surgery laparoscopically, is it possible to achieve such results? For a surgeon who is extremely skilled and well versed in laparoscopic techniques, laparoscopic lymph node dissection, vessel dissection, intestinal tube freeing, ligament cutting, intestinal segment removal, and GI reconstruction are not difficult, and after these operations are completed, only a very small incision in the abdomen is needed to remove the surgical specimen. As a result, the incision is smaller, the location chosen is more discreet and aesthetically pleasing, the abdominal cavity is exposed for a shorter period of time, and the patient recovers more quickly after surgery. And this is “complete laparoscopic surgery”. The most important technical difficulty of complete laparoscopic surgery for colon cancer is the reconstruction of the digestive tract. In recent years, with the development of laparoscopic instruments and equipment, the application of laparoscopic cutting closures has made the overlapping triangular anastomosis of colon not only safe and reliable, but also more in line with the physiological function; and after the fluorescent laparoscope has entered the clinic, the surgeon no longer needs to be brain-dead to judge whether the blood supply of the anastomosis is rich or not, which greatly ensures the safety of laparoscopic anastomosis. Currently, clinical studies at home and abroad have confirmed that “complete laparoscopic surgery” for colon cancer causes less damage and faster recovery than conventional “laparoscopic-assisted surgery”. Then, what are the advantages of “complete laparoscopic surgery” for patients? 1. The incision after surgery is shorter. For “laparoscopic assisted surgery”, the intestinal tube, mesentery and omentum with tumor need to be removed from the body through the incision during the surgery, and the tumor cannot be squeezed, so the incision must be much larger than the tumor to facilitate the removal of the specimen. Patients in the north are often fat, so if the tumor is 5cm long, the incision needs to be 10cm to facilitate the operation. Therefore, the incision can be as small as possible because there is no need to worry about whether the tumor will be pulled or squeezed during the process of specimen removal, which will lead to the spread of cancer cells. In the past, the incision needed to be 10cm long, but at this time, the operation can be completed with only 6-7cm. 2. The incision is more concealed and beautiful. Generally speaking, the auxiliary incision for right hemicolectomy is a vertical incision in the middle of the umbilicus, for transverse colectomy is a vertical incision in the middle of the upper abdomen, and for left hemicolectomy is a vertical incision in the middle of the umbilicus or upper abdomen or through the rectus abdominis muscle. In contrast, the incision for complete laparoscopic surgery has more sites to choose from, as this incision is only used to remove the specimen. Therefore, if the patient has had previous abdominal surgery, the original surgical incision can be borrowed, such as the original appendectomy incision, the original cesarean incision, or the original gallbladder surgery incision. If the patient has not had previous abdominal surgery, and the tumor is small and the patient is thin, we can remove the specimen through the rectum in men and the vagina in women, so that there is no incision on the abdomen after the surgery, but only a few puncture holes, which is the most popular NOSES procedure in the field of surgery. Even if a new incision is still needed to remove the specimen from the abdomen at the end of the surgery, we can make a small transverse incision on the pubic bone of the lower abdomen to remove the specimen, relying on the postoperative body hair of the patient’s lower abdomen to cover the incision, or relying on the skin lines of the lower abdomen to cover the incision, thus making the incision more concealed and beautiful. 3.Faster recovery of intestinal function after surgery. Since the role of the abdominal incision during “complete laparoscopic surgery” is only to remove the specimen, the abdominal cavity is open and directly exposed to the air for a shorter period of time, so the inflammation and other reactions in the abdominal cavity are less severe and there are fewer postoperative adhesions. Therefore, the patient may resume exhaustion on the first day after surgery, and can eat a liquid or semi-liquid diet. 4. Less use of pain medication. Since the incision of complete laparoscopic surgery is shorter, and fewer skin sensory nerve fibers are cut by the transverse incision, and the incision in the lower abdomen is less stretched by respiratory movements, the incision pain is lighter and thus less dependent on pain medication after surgery. 5. Earlier resumption of postoperative activities on the ground. Since there is no incision in the abdomen or only a small transverse incision in the lower abdomen after complete laparoscopic surgery for colon cancer, patients have no pain or the pain of the wound is mild when they move around, so they can freely move around on the first day after surgery, which can reduce a series of complications caused by bed rest, such as lung infection, deep vein thrombosis in the lower limbs and abdominal fluid infection. 6. Shorter hospitalization time and lower cost. Since complete laparoscopic surgery for colon cancer causes less damage to patients, has lower complication rate and faster recovery of intestinal function after surgery, the hospital stay is shorter and patients can often be discharged home three or four days after surgery, thus saving hospitalization cost.