This study aimed to compare the clinical and psychological outcomes of patients who underwent LAR with those of patients who underwent LAR-NOSE for high rectal and sigmoid colon cancer. Our results show that the outcomes of LAR-NOSE patients were superior in terms of postoperative pain, anxiety, and depression. Even without an abdominal incision, patients’ postoperative pain was slightly lower after LAR-NOSE than after LAR.
The patients in both groups were most likely worried or fearful about colorectal cancer diagnosis and radical surgery, as the baseline anxiety and depression scores were similar between the two groups. This type of state-related anxiety can be relieved after surgery. However, the different surgeries caused different levels of postoperative anxiety and depression[29], where the surgical outcomes were closely connected to postoperative anxiety and depression[30]. For example, a low risk of incision dehiscence and better postoperative clinical recovery results were noted in the LAR-NOSE group. As expected, the postoperative SAS, SDS, and STAI scores reflected greater psychological well-being in the LAR-NOSE patients. The prevalence of depression and anxiety in patients with colorectal cancer is approximately 57%[15]. Therefore, patients with high anxiety and depression levels may benefit psychologically from LAR-NOSE.
In patients with colorectal cancer, postoperative pain has been associated with psychological well-being; thus, it is important to recognize and treat it appropriately[31]. Our results demonstrate that transrectal LAR-NOSE surgery can significantly reduce postoperative pain (Table 3); thus, the postoperative anxiety levels in LAR-NOSE patients are expected to be lower than those in LAR patients. The differences may appear immediately after surgery as there may be a short period of depression due to surgical stress and anesthesia; however, after the anticipation subsided, there was not much difference between the two patient groups.
The surgical results showed no differences based on the T or N stage or the distance from the tumor to the verge between the two groups. Since LAR-NOSE does not require opening the abdominal wall for specimen extraction[32], the operative time was shorter, and intraoperative blood loss was less than those in the LAR group (Table 2). Total laparoscopic bowel reconstruction in LAR-NOSE avoids unnecessary damage to the abdominal viscera, which leads to faster recovery of intestinal function, less pain, lower rate of surgical complications, and shorter postoperative hospital stay.
The oncological outcomes and local recurrence are a priority during any transrectal LAR-NOSE procedure. Our study showed that the anastomotic recurrence rates and 5-year DFS were not different between the two patient groups. This could be due to the use of a sleeve specimen bag during surgery, which improves the method of specimen extraction and stapling anvil insertion into the proximal colon[33]. Specifically, our experience with transrectal LAR-NOSE indicates three important procedures: (1) putting the specimen protector into the abdomen using the 12-mm tractor while maintaining sterility, (2) inserting the stapling anvil through the sleeve bag and placing it into the sigmoid colon, and (3) removing the tumor using the protection sleeve. These measures are effective in avoiding intra-abdominal infection and decrease the residual tumor during transrectal LAR-NOSE.
This study shows that transrectal LAR-NOSE is a safer and more feasible colorectal cancer treatment than LAR. Patients who underwent LAR-NOSE treatment had better psychological function and rapid clinical recovery. However, the failure rate of transrectal specimen extraction and conversion to conventional laparoscopy was relatively high because of the learning curve in the early stages of the study. NOSE failures in LAR-NOSE were likely due to patient obesity, large tumor size, mesentery thickening, and a narrow pelvis.
The current study has several limitations. First, factors that affect the feasibility of performing transrectal LAR-NOSE were not included and therefore need to be retrospectively studied to define risk parameters. Second, the patients included in this prospective randomized controlled study were relatively few, and the participants were all recruited from a single center. The clinical efficacy and psychological function of patients who undergo LAR-NOSE should be confirmed by a multicenter prospective case–control trial with a larger sample size in future studies.