[Advances in tumor regression patterns and safe distance of distal resection margin after neoadjuvant therapy for rectal cancer].

Neoadjuvant therapy has been widely applied in the treatment of rectal cancer, which can shrink tumor size, lower tumor staging and improve the prognosis. It has been the standard preoperative treatment for patients with locally advanced rectal cancer. The efficacy of neoadjuvant therapy for rectal cancer patients varies between individuals, and the results of tumor regression are obviously different. Some patients with good tumor regression even achieve pathological complete response (pCR). Tumor regression is of great significance for the selection of surgical regimes and the determination of distal resection margin. However, few studies focus on tumor regression patterns. Controversies on the safe distance of distal resection margin after neoadjuvant treatment still exist. Therefore, based on the current research progress, this review summarized the main tumor regression patterns after neoadjuvant therapy for rectal cancer, and classified them into three types: tumor shrinkage, tumor fragmentation, and mucin pool formation. And macroscopic regression and microscopic regression of tumors were compared to describe the phenomenon of non-synchronous regression. Then, the safety of non-surgical treatment for patients with clinical complete response (cCR) was analyzed to elaborate the necessity of surgical treatment. Finally, the review studied the safe surgical resection range to explore the safe distance of distal resection margin.

[A prospective cohort study on the clinical value of pelvic peritoneal reconstruction in laparoscopic anterior resection for middle and low rectal cancer].

Objective: To investigate the safety and efficacy of pelvic peritoneal reconstruction and its effect on anal function in laparoscopy-assisted anterior resection of low and middle rectal cancer. Methods: A prospective cohort study was conducted. Consecutive patients with low and middle rectal cancer who underwent laparoscopy-assisted transabdominal anterior resection at Naval Military Medical University Changhai Hospital from February 2020 to February 2021 were enrolled. Inclusion criteria: (1) the distance from tumor to the anal verge ≤10 cm; (2) laparoscopy-assisted transabdominal anterior resection of rectal cancer; (3) complete clinical data; (4) rectal adenocarcinoma diagnosed by postoperative pathology. Exclusion criteria: (1) emergency surgery; (2) patients with a history of anal dysfunction or anal surgery; (3) preoperative diagnosis of distant (liver, lung) metastasis; (4) intestinal obstruction; (5) conversion to open surgery for various reasons. The pelvic floor was reconstructed using SXMD1B405 (Stratafix helical PGA-PCL, Ethicon). The first needle was sutured from the left anterior wall of the neorectum to the right. Insertion of the needle was continued to suture the root of the sigmoid mesentery while the Hemo-lok was used to fix the suture. The second needle was started from the beginning of the first needle, after 3-4 needles, a drainage tube was inserted through the left lower abdominal trocar to the presacral space. Then, the left peritoneal incision of the descending colon was sutured, after which Hemo-lok fixation was performed. The operative time, perioperative complications, postoperative Wexner anal function score and low anterior resection syndrome (LARS) score were compared between the study group and the control group. Three to six months after the operation, pelvic MRI was performed to observe and compare the pelvic floor anatomical structure of the two groups. Results: A total of 230 patients were enrolled, including 58 who underwent pelvic floor peritoneum reconstruction as the study group and 172 who did not undergo pelvic floor peritoneum reconstruction as the control group. There were no significant differences in general data between the two groups (all P>0.05). The operation time of the study group was longer than that of control group [(177.5±33.0) minutes vs. (148.7±45.5) minutes, P<0.001]. There was no significant difference in the incidence of perioperative complications (including anastomotic leakage, anastomotic bleeding, postoperative pneumonia, urinary tract infection, deep vein thrombosis, and intestinal obstruction) between the two groups (all P>0.05). Eight cases had anastomotic leakage, of whom 2 cases (3.4%) in the study group were discharged after conservative treatment, 5 cases (2.9%) of other 6 cases (3.5%) in the control group were discharged after the secondary surgical treatment. The Wexner score and LARS score were 3.1±2.8 and 23.0 (16.0-28.0) in the study group, which were lower than those in the control group [4.7±3.4 and 27.0 (18.0-32.0)], and the differences were statistically significant (t=-3.018, P=0.003 and Z=-2.257, P=0.024). Severe LARS was 16.5% (7/45) in study group and 35.5% (50/141) in control group, and the difference was no significant differences (Z=4.373, P=0.373). Pelvic MRI examination 3 to 6 months after surgery showed that the incidence of intestinal accumulation in the pelvic floor was 9.1% (3/33) in study group and 46.4% (64/138) in control group (χ(2)=15.537, P<0.001). Conclusion: Pelvic peritoneal reconstruction using stratafix in laparoscopic anterior resection of middle and low rectal cancer is safe and feasible, which may reduce the probability of the secondary operation in patients with anastomotic leakage and significantly improve postoperative anal function.

Retrospective study of the functional and oncological outcomes of conformal sphincter preservation operation in the treatment of very low rectal cancer.

BACKGROUND: Conformal sphincter preservation operation (CSPO) is a new surgical procedure for very low rectal cancers (within 4-5 cm from the anal verge). CSPO preserves more of the dentate line and distal rectal wall and also avoids injuring nerves in the intersphincteric space, resulting in satisfactory anal function after resection. The aim of this study was to analyze the short-term surgical results and long-term oncological and functional outcomes of CSPO. METHODS: Consecutive patients with very low rectal cancer, who had CSPO between January 2011 and October 2018 at Changhai Hospital, Shanghai were included. Patient demographics, clinicopathological features, oncological outcomes and anal function were analyzed. RESULTS: A total of 102 patients (67 men) with a mean age of 56.9 ± 10.8 years were included. The median distance of the tumor from the anal verge was 3 (IQR, 3-4) cm. Thirty-five patients received neoadjuvant chemoradiation (nCRT). The median distal resection margin (DRM) was 0.5 (IQR, 0.3-0.8) cm. One patient had a positive DRM. All circumferential margins were negative. There was no perioperative mortality. The postoperative complication rate was 19.6%. The median duration of follow-up was 28 (IQR, 12-45.5) months. The local recurrence rate was 2% and distant metastasis rate was 10.8%. The 3-year overall survival and disease-free survival rates were 100% and 83.9%, respectively. The mean Wexner incontinence and low anterior resection syndrome scores 12 months after ileostomy reversal were 5.9 ± 4.3, and 29.2 ± 6.9, respectively. CONCLUSIONS: For patients with very low rectal cancers, fecal continence can be preserved with CSPO without compromising oncological results.

Treatment for early ultralow rectal cancer: pull-through intersphincteric stapled transection and anastomosis (PISTA) versus low anterior resection.

BACKGROUND: The aim of this study was to compare the functional and oncologic results of pull-through intersphincteric stapled transection and anastomosis (PISTA) with low anterior resection (LAR) in the treatment for early ultralow rectal cancer. METHODS: A total of 278 patients with early ultralow rectal cancer were retrospectively included and analyzed, with 136 in the PISTA group and 142 in the LAR group. RESULTS: Gender, age, tumor diameter, distance from the dentate line to the inferior margin of the tumor, tumor stage, length of operation and postoperative complications were comparable in the two groups. Compared with the LAR group, the PISTA group had a more accurate distal transection site, a lower daily fecal frequency (6 (5-7) vs. 8 (7-9), p < 0.001) and a lower Wexner incontinence score (13 (10-14) vs. 14 (13-16), p < 0.001) 3 months after ileostomy reversal, and a higher rate of satisfactory fecal continence (97.1 % vs. 90.8 %, p = 0.043). The follow-up period of the PISTA group was similar to that of the LAR group (56 (30-81) months vs. 54 (30-80) months, p = 0.982). The PISTA group was associated with a lower local recurrence rate (2.2 % vs. 11.3 %, p = 0.003). Kaplan-Meier analysis also showed that the PISTA group was associated with longer overall survival (p = 0.018) and longer local recurrence-free survival (p = 0.004) than the LAR group, while distant metastasis-free survival (p = 0.896) was comparable in the two groups. Multivariate analysis identified lymph node metastasis (p < 0.001) and operation (PISTA vs. LAR, p = 0.031) as independent predictive factors for local recurrence-free survival. CONCLUSIONS: PISTA is a technically simple, oncologically safe and functionally favorable procedure for the treatment for early ultralow rectal cancer.

Diffuse cavernous hemangioma of the rectosigmoid colon.

Diffuse cavernous hemangioma of the rectosigmoid colon is an uncommon benign vascular lesion. We report 5 cases of diffuse cavernous hemangioma, focusing on the clinical features, diagnosis procedure and treatment. Five patients have undergone sphincter-saving procedures, 3 cases had coloanal sleeve anastomoses and 1 patient each had pull-through anastomosis and lower anterior resection. During the follow-up, which ranged from 3 to 10 years, 3 patients had no further anal bleeding and 2 patients had minor intermittent anal bleeding. Continence for normal stool was satisfactory in all patients. In conclusion, sphincter-saving procedure is most appropriate and curative approach for the treatment of diffuse cavernous hemangioma. Imaging study plays an important role in the diagnosis, preoperative staging and follow-up.

[Improvement in the resection of intestinal Peutz-Jeghers polyps].

Polyps in patients with Peutz-Jeghers syndrome (PJS) are found in the large and small bowels. In the past, intestinal polyps were treated mainly by multiple abdominal operations. The authors reported resecting 259 polyps in 13 patients with PJS by laparotomy plus colonoscopy via small bowel incision for small intestines, and/or plus colonoscopy via the anus for ileum and large bowel polyps at a time combined with periodic colonoscopy via the anus for colorectal polyps. The largest polyp resected in this way was 10 x 9 x 8 cm. As many as 46 polyps were resected by snare polypectomy at a single colonoscopic attempt. Using the above-mentioned methods, multiple intestinal polyps can be resected more thoroughly, and postoperative recurrence and complication became less frequent.