The incidence rate of rectal cancer is high. The most common cases are middle and low rectal cancer. The early symptoms are mostly atypical. For patients with middle and low rectal cancer, laparoscopic radical resection is more frequently used, especially for low rectal cancer (distance from anus less than 5cm), ELAPE operation is adopted. After the surgery, peritoneal pelvic hernia, intestinal obstruction, perineal incision infection, and other complications may occur. Although laparoscopic surgery can reduce the infection of the abdominal incision, the perineum is associated with postoperative complications. The disease still faces a significant challenge [10].
TME operation, especially the side lymph node operation can damage the pelvic floor structure, large perineum incision, suture under high tension, neoadjuvant radiotherapy and chemotherapy, and pelvic cavity residuals[11, 12]. At present, the pelvic floor peritoneal reconstruction is divided into isolation technology and filling technology. Previous reports showed that biological patches could be used to strengthen the peritoneum structure of the pelvic floor[13]. However, it increased the cost of operation, and the probability of infection and internal hernia may occur in the patch. Therefore, it also limits the clinical use of the patch. There are also reports that omental plasty is often used to eliminate the invalid cavity of the pelvic cavity after operation. However, it cannot improve the healing of the perineal incision and increase the incidence of pelvic floor peritoneal hernia [14].
Laparoscopic pelvic floor peritoneal reconstruction is challenging. Improper pelvic floor peritoneal sutures may lead to residual suture space, improving the risk of postoperative internal hernia. Wang[15] reconstructs the pelvic floor peritoneum with a Hem-o-lok clip; however, it still has the risk of intestinal obstruction due to the small intestine herniation. The results showed no significant difference between the patients in PPR group and non-PPR group, but the obstruction of the PPR group was significantly lower than non-PPR group. One patient in the non-PPR group was ineffective after conservative treatment due to mechanical intestinal obstruction. After an operation, the end of the operation was found, ileum fell into the right pelvic floor and formed adhesion with the pelvic floor. The reconstruction of the pelvic floor peritoneum and the restoration of the continuity of the pelvic floor peritoneum can effectively prevent the intestinal obstruction caused by the adhesion of the pelvic floor tissue due to the intestinal tract decline. The fibrosis of pelvic floor tissue after neoadjuvant radiotherapy and chemotherapy was prominent [5]. There was no extra peritoneum in reconstructing the pelvic floor peritoneum, leading to continuous suture and reconstruction of the peritoneum. Shen et al. proposed that the free bladder back wall flap supplement the pelvic floor isolation technique[16]. We found statistical differences in the operation time between the two groups, but the stratified analysis of the two groups found no difference in the operation time of the upper and middle rectal cancer. However, there was a statistical difference in the time of low rectal cancer, which was related to the size of the tumor and the tumor location. However, we found that the prolonged operation time did not increase the postoperative pulmonary infection and other perioperative complications.
The incidence of anastomotic leakage was statistically different between the two groups. The reason of leakage was related to the tumor site. There were more patients with middle and low rectal in the group of closing the pelvic floor peritoneum. However, the reoperation rate of patients in PPR group was significantly lower than non-PPR group, and the reoperation rate was statistically significant. Therefore, we believe that reconstruction of the pelvic floor peritoneum can effectively seal the dead cavity of the pelvic floor. Even if the anastomotic leakage occurs, the contaminated liquid will not pollute the whole abdominal cavity and even cause severe abdominal infection, even infectious shock. Meanwhile, if the abdominal cavity drainage is smooth, most patients can be cured by conservative treatment, and the hospitalization time is not increased significantly. There was one case of presacral effusion in PPR group, 5 cases in the non-PPR group, but there was no statistical significance between the two groups. However, presacral effusion may cause presacral infection and lead to the laceration of incision of the pubic part and the risk of delayed healing. The reconstruction of the pelvic floor peritoneum can isolate the dead cavity of the pelvic floor, limit the further expansion of the effusion. Moreover, drainage through the perineum incision can also reduce the presacral effusion to the greatest extent.
Pelvic floor peritoneal hernia is a rare and complex complication after elape. The incidence of perineal hernia after laparoscopic radical resection of rectal cancer is 2.15% − 13%[17]. Surgery is only treatment option for a symptomatic perineal hernia. However, the recurrence rate of perineal hernia is still high after operation repair. It has been reported that the recurrence rate of perineal hernia is more than 50%[18]. Therefore, the prevention of peritoneal pelvic hernia is particularly important in elape. The results showed no pelvic floor hernia in the PPR group, while one case in the non-PPR group had a postoperative pelvic floor hernia. This patient had anorectal distension and was cleared by abdominal CT, but no operation was performed, there was no statistical difference between the two groups. Most of the pelvic floor peritoneal hernia has no clinical symptoms and has delayed characteristics. Only a short-term effect is observed in this study and the follow-up time is short; thus the long-term incidence of pelvic floor peritoneal hernia may be different [17]. Therefore, we believed that the reconstruction of the pelvic floor peritoneum could prevent the postoperative pelvic floor peritoneal hernia.
The open position of the pelvic peritoneum is close to the mesentery when laparoscopic operation, aiming to keep as much peritoneum as possible to facilitate the closure of the pelvic floor peritoneum. However, there is still a high tension in the peritoneum of the pelvic floor, leading to suture cracking or secondary hernia. The needle angle needs to be adjusted several times to meet the master knife and assistant proficiency requirements. The barb thread is embedded in the suture due to tiny barbs on the suture. The surrounding tissue can form self-fixation without knots, and it is easy to operate and save time. It has the following advantages: (1). It is a rapid and simple pelvic floor peritoneal reconstruction method, which is cheaper than patch repair. (2). The reinforcement of the perineal incision can reduce the incidence of perineal hernia. (3). It can prevent intestinal adhesion and obstruction caused by intestinal tract slide. 4. It can reduce drainage between the pelvis and the abdomen to reduce infection risk in abdominal and perineal incisions.