Colorectal cancer is a common malignant tumor in China, and its incidence rate is increasing year by year. In economically developed regions, the incidence rate of colorectal cancer has risen from the fourth place of malignant tumors to the third place after lung cancer and gastric cancer, becoming a disease that seriously threatens human life safety. At present, the treatment of colorectal cancer is still mainly based on surgical resection. Whether sufficient intestinal margins, thorough lymph node dissection and whole tissue specimen removal can be achieved becomes the standard of whether the surgery is curative or not, and also becomes the criterion to measure whether a surgical method is suitable to be carried out.
Among the advances in surgical techniques for colorectal cancer, the concept of rectal mesorectal excision was introduced, giving rise to the new technical standard of total mesorectal excision (TME Total Mesorectal Excision) for rectal cancer surgery. And in 1991, the first laparoscopic colorectal surgery was performed, marking the formation of a new technique of colorectal surgery [. In the 1990s, laparoscopic surgery for colorectal cancer, which was not carried out rapidly, was mainly hampered by some debates involving laparoscopic techniques, including whether laparoscopic surgery for colorectal cancer could achieve the goal of radical tumor cure, and the effect of CO2 pneumoperitoneum of laparoscopic surgery on distant tumor implantation and incisional implantation.
In recent years, with the maturity of laparoscopic surgery technology for colorectal cancer and the report of the results of prospective controlled studies of laparoscopic surgery and open surgery in a large number of cases around the world, these controversies have been settled and laparoscopic surgery for colorectal cancer has been developed rapidly, making the completion of the first laparoscopic colorectal surgery more than ten years ago a milestone of new technology for the radical treatment of colorectal cancer surgery.
1.Indications and contraindications of laparoscopic colorectal cancer surgery
What kind of colorectal cancer patients are suitable for laparoscopic surgery? Similar to laparoscopic cholecystectomy, it is mostly used for patients with simple gallbladder stones or gallbladder polyps at the beginning. With the improvement of surgical techniques and methods, laparoscopic surgery is used not only in the above conditions, but also in patients with acute gallbladder inflammation or combined with bile duct stones.
At the beginning of laparoscopic colorectal surgery, it was only used in patients with benign colorectal diseases, such as Croln’s disease, ulcerative colitis, colonic diverticulosis and colorectal polyps, and even in patients with cancer, it was mostly limited to the early stage of the tumor. With the clarification of the radical effect of laparoscopic surgery and the affirmation of the safety of laparoscopic surgery, it is now believed that the vast majority of patients with colorectal cancer are suitable for laparoscopic surgery, especially for patients with combined cardiopulmonary diseases, because laparoscopic surgery is less traumatic, with light postoperative pain, early postoperative recovery of intestinal function, patients can get out of bed early, and moreover, the risk of postoperative pulmonary infection and deep vein thrombosis of lower limbs is reduced. Therefore, these patients are more suitable for laparoscopic surgery.
For tumors with diameter greater than 10 cm, tumors that have invaded surrounding organs, excessive obesity, intestinal obstruction, serious abdominal adhesions, and patients with diseases contraindicated for open surgery, laparoscopic surgery is not recommended.
2.Operation and principles of laparoscopic surgery for colorectal cancer
Colorectal resection because of tumor, whether laparoscopic surgery or open surgery is chosen, must be performed according to the basic principles and operations of tumor treatment. Laparoscopic techniques, with the continuous improvement and innovation of operating instruments and the description of new methods are constantly evolving. However, in general, the freeing and dissection of the intestine in laparoscopic surgery are done in the abdominal cavity.
The ligation and severing of large vessels is also done intraperitoneally by titanium clips or linear cutting anastomoses, followed by small incisions of about 5 cm in the abdominal wall to complete the removal of the specimen and the anastomosis of the intestinal canal outside the body. The resection of the sigmoid colon and rectum, including the dissection and reanastomosis of the distal intestinal canal, is also accomplished intraperitoneally using a linear cutting anastomosis and a tubular anastomosis.
Laparoscopic surgery for colorectal cancer follows the principles of open tumor radical resection of the tumor and surrounding tissues as a whole; (2) non-tumor contact techniques that prioritize ligation of associated vessels and manipulation during surgery; and (3) systematic and thorough lymphatic dissection. In the early days of laparoscopic techniques for radical resection of colorectal cancer, there was debate about the ability of laparoscopic surgery to achieve the same extent of radical debridement as open surgery.
The standard open radical surgery for colorectal cancer includes right hemicolectomy, left hemicolectomy, anterior rectal resection with submesenteric arteriovenous ligation dissection, and combined transabdominal perineal resection, including radical rectal cancer surgery with total rectal mesenteric resection. These standard surgical approaches have also become the standard procedure for laparoscopic surgery, which also allows for better surgical views and anatomical levels than open surgery under conditions of pelvic stenosis and low tumor location.
Currently, all retrospective or prospective studies related to laparoscopic colorectal surgery have reported that in laparoscopic colorectal cancer surgery, the principle of radical tumor treatment is observed, and in the pathological examination of surgically resected specimens, the number of lymph nodes in the specimen, the distal and proximal ends of the resected intestinal specimen, and the length of the tissue margins and resected bowel segments in the specimen do not differ in comparison with open surgery.
The disadvantage of laparoscopic surgery is that the touch of the surgeon’s hand is missing during laparoscopy. For tumors growing intraluminally, it is more difficult to determine the exact site of the tumor during laparoscopy if the plasma layer is not invaded. Therefore, adequate preoperative evaluation preparation and tumor localization are necessary. The choice of preoperative barium enema angiography for tumor localization or preoperative injection staining of the tumor site by conventional enteroscopy reduces the dilemma of getting into intraoperative inability to localize the tumor.
In addition, if intraoperative localization remains impossible, intraoperative colonoscopy can also be performed to complete the procedure in collaboration. For intraoperative difficulties in laparoscopy, it is very necessary to timely transit open abdomen when tumor is found to invade the surrounding organs, tumor is too large, serious adhesions in the abdominal cavity or important organs such as ureter cannot be identified, so as to avoid surgical complications and reduce unnecessary surgical risks and costs for patients.
From the literature, it is reported that in some large medical centers, the rate of intermediate open abdomen is between 5% and 21%, so surgeons should have a clear idea that intermediate open abdomen is not a failure of laparoscopic surgery.
Laparoscopic radical colorectal cancer surgery requires not only skillful laparoscopic surgery experience, but also extensive expertise in colorectal tumors. In the early stage of laparoscopic colorectal tumor surgery, it is normal to have a longer operation time and a higher rate of intermediate open abdomen. What is to be avoided is a higher rate of complications, which can bring some unnecessary adverse effects and lead to setbacks in the development of the new technology.
Therefore, the necessary training in laparoscopic surgical techniques to complete a certain number of laparoscopic surgical resections of benign colorectal diseases is necessary before performing this new procedure. Currently, there are international admission standards for laparoscopic colorectal cancer surgery. The ASCRS the American Society of Colon and Rectal Surgeons recommends that at least 20 cases of benign colorectal laparoscopic surgery must be experienced before performing radical lumpectomy for colorectal cancer.
3. Short-term efficacy evaluation of laparoscopic colorectal cancer surgery
In laparoscopic gallbladder surgery, the advantages embodied by the laparoscopic technique are recognized. Namely, there is basically no postoperative analgesic treatment, early postoperative rehabilitation of gastrointestinal function and short hospital stay. In laparoscopic colorectal cancer surgery, several studies comparing laparoscopic surgery with open surgery have found the same advantages of this technique.
Short-term postoperative quality of life was evaluated in terms of postoperative patient pain and the need for analgesic medication. In the COST trial, patients in the open group required 4 days of intravenous anesthetic analgesics, whereas the laparoscopic group required only 3.2 days of extra-gastrointestinal analgesics. In another randomized controlled study, the difference embodied by the two groups was in the amount of morphine administered on the first postoperative day.
Most of the current studies show that after laparoscopic colorectal surgery, patients recover gastrointestinal function earlier than after open surgery and start eating significantly earlier. The recovery of gastrointestinal function after laparoscopic surgery, as marked by the return of anal evacuation or bowel movements, is on average 1 day earlier, as shown in Table 2.
Either liquid or solid food was also, on average, 1 day earlier. Both early recovery of gastrointestinal function and earlier resumption of food contribute to a shorter hospital stay for patients after laparoscopic colorectal surgery. In the COST study, the median length of stay was 5 days, which was 1 day less than for open surgery. This was also confirmed by a randomized controlled study in Europe.
In terms of complication rates and mortality after surgery, there was no significant difference between open and laparoscopic surgery from the current published literature. This was confirmed by three large samples of randomized clinical studies. In terms of intraoperative blood loss, two studies showed less than 100 ml of intraoperative blood loss in both laparoscopic procedures, but some other studies found no difference between the two groups.
In most of the clinical studies reported, the incidence of each individual complication (e.g., wound infection or anastomotic leak) was not statistically different between the laparoscopic and open surgery groups. However, when these complications were analyzed together, one group of studies found that the complication rate was higher in the open surgery group (31/108) than in the laparoscopic group (12/111, p=0.001).
4. Evaluation of long-term efficacy of laparoscopic colorectal cancer surgery
Compared with surgery for benign diseases, surgery for malignant tumors involves the radical effect of surgery on the tumor. Therefore, to evaluate the surgical quality of laparoscopic colorectal cancer surgery, the recurrence of tumor after surgery and the long-term survival rate of patients are very important indicators. The results of a large number of clinical studies have shown that there is no significant difference in long-term efficacy between the laparoscopic group and the open surgery group for radical surgery of colorectal cancer, which follows the same principles of radical tumor treatment, and also the results of some studies have found that its long-term efficacy is even better than that of open surgery.
Recurrence of tumor
The recurrence of tumors are distant metastases, abdominal implants, incisional implants and in situ recurrence. In the early days of laparoscopic surgery, there were clinical reports of tumor implantation rates of up to 21% in the perforation hole, however, recent studies have not confirmed this. In a large sample of prospective multiple randomized controlled studies COST reported incisional implantation rates as low as 0.5% and 0.2% in both the laparoscopic and open groups, respectively.
In addition, the results of several other single-center clinical studies did not find a difference between the two groups. lacy reported [only one case of perforator implantation in 106 patients undergoing laparoscopic surgery and no incisional recurrence in the open group. In a large case-control study in Hong Kong (n=403), there was not a single case of incisional recurrence in either the laparoscopic or open group.
And there was a similar recurrence rate between laparoscopic and open surgery in terms of recurrence at the primary site of the tumor. This is confirmed by the results of both single-center clinical studies and multicenter collaborative clinical studies. the largest clinical study COST (n=872 cases) published in 2004, which followed patients (median time) for 4.4 years, found no difference in local recurrence rates between the two groups.