Definition and grading of anastomotic stricture/stenosis following low anastomosis after total mesorectal excision: A single-center study.

BACKGROUND: Anastomotic stricture/stenosis (AS) is an alarming complication after colorectal surgery, and there is still no recognized definition for AS. This study aimed to determine the status and change of AS after rectal surgery using a special AS definition and grading system, discuss various risk factors for AS. METHODS: This study included patients with rectal cancer who underwent total mesorectal excision between May 2014 and May 2021. A five-degree special AS definition and grading system was used to determine AS status, and clinical outcomes and risk factors for AS were investigated. RESULTS: A total of 473 patients were enrolled in this study. Univariate and multivariate analyses of patient-related and technical risk factors for AS were performed 3 months postoperatively. For univariate analysis, female sex was a lower risk factor for AS. Defunctioning stoma, neoadjuvant chemoradiotherapy, chemotherapy, and anastomotic leakage were higher risk factors for AS (all p < 0.05). For multivariate analysis, only neoadjuvant chemoradiotherapy, chemotherapy, and anastomotic leakage were still higher risk factors for AS (all p < 0.05). CONCLUSIONS: Through a special AS definition and grading system's evaluation, we noted that neoadjuvant chemoradiotherapy, chemotherapy, and anastomotic leakage were the higher risk factors for AS.

MiR-200c/FUT4 axis prevents the proliferation of colon cancer cells by downregulating the Wnt/ß-catenin pathway.

BACKGROUND: MicroRNA (miR)-200c has been widely reported to be involved in colon cancer progress. However, the mechanisms of miR-200c in regulating tumor metastasis and growth remain to be fully elucidated. This study aimed to investigate the mechanism of miR-200c targets fucosyltransferase 4 (FUT4) on the proliferation of colon cancer. METHODS: The miR-200c and FUT4 mRNA levels in LoVo and SW480 cells were measured by real-time quantitative polymerase chain reaction. Further, miR-200c mimic, FUT4 siRNA and FUT4 mimic were transfected into cells, separately. Cell counting kit-8, plate colony formation and transwell assays were used to analyse the cells biological behaviour.. Immunofluorescence was used to analyse the Ki-67 expression Moreover, the Wnt/ß-catenin pathway-related proteins were detected by western blots. A double luciferase experiment was performed to confirm the relationship between miR-200c and FUT4. In vivo, tumour growth and Wnt/ß-catenin pathway-related proteins were also analysed. RESULTS: In vitro, the expression of miR-200c and FUT4 were negatively correlated in LoVo and SW480 cells (correlation coefficients were - 0.9046 and - 0.9236, respectively). MiR-200c overexpression inhibited the proliferation, migration and invasion of LoVo and SW480 cells by downregulating FUT4. The Ki67-positive cells and Wnt/ß-catenin signalling pathway-related proteins were reduced in the miR-200c overexpression and FUT4 silencing groups. A dual luciferase reporting system identified FUT4 as the target of miR-200c. The results in vivo were further confirmed the foundation of cells study. CONCLUSIONS: In summary, miR-200c overexpression inhibits proliferation of colon cancer targeting FUT4 to downregulate the Wnt/ß-catenin pathway, which promises molecular targets to inhibit metastasis for colon cancer therapy.

Rectoseminal vesicle fistula after radical surgery for rectal cancer: Four case reports and a literature review.

BACKGROUND: A rectoseminal vesicle fistula (RSVF) is a rare complication after anterior or low anterior proctectomy for rectal cancer mainly due to anastomotic leakage (AL). Limited literature documenting this rare complication is available. We report four such cases and review the literature to investigate the etiology, clinical manifestations, and the diagnostic and treatment methods of RSVF in order to provide greater insight into this disorder. CASE SUMMARY: Four cases of RSVF were presented and summarized, and a further 12 cases selected from the literature were discussed. The main clinical symptoms in these patients were pneumaturia, fever, scrotal swelling and pain, anal pain, orchitis, diarrhea, dysuria, epididymitis and fecaluria. Imaging methods such as pelvic X-ray, computed tomography (CT), sinus radiography, barium enema and other techniques confirmed the diagnosis. CT was the imaging modality of choice. In cases presenting with reduced levels of AL, minimal surrounding inflammation, and controlled infection, the RSVF was conservatively treated by urethral catheterization, antibiotics administration and parenteral nutrition. In cases of severe RSVF, incision and drainage of the abscess or fistula and urinary or fecal diversion surgery successfully resolved the fistula. CONCLUSION: This study provides an extensive analysis of RSVF, and outlines, summarizes and examines the causes, clinical manifestations, diagnostic procedures and treatment options, in order to prevent misdiagnosis and treatment errors.

miR-22 Suppresses Tumor Invasion and Metastasis in Colorectal Cancer by Targeting NLRP3.

PURPOSE: This study aimed to investigate the effects of microRNA (miR)-22 on biological behaviors of colon cancer cells and to explore the relationship between miR-22 and NLRP3. MATERIALS AND METHODS: First, human colon cancer HCT116 cells were transfected with a miR-22 mimic, miR-22 inhibitor, control mimic, and control inhibitor, respectively. CCK8, colony formation, and transwell assays were performed to observe cell proliferation, migration, and invasion. Western blotting was used to analyze the expression of recombinant NLRP3 (NLR family, pyrin domain-containing protein 3) and epithelial-mesenchymal transformation (EMT)-related proteins. The target relationship between miR-22 and NLRP3 was verified by double luciferase report. Second, an NLRP3 inhibitor and NLRP3 mimic were transfected into HCT116 cells, and the biological behaviors and EMT-related proteins were again observed. Finally, a nude mouse xenograft model was constructed to verify the above results. RESULTS: In vitro, compared with the control group, administration of the miR-22 mimic significantly decreased proliferation, migration, and invasion of HCT116 cells, whereas the miR-22 inhibitor markedly increased their proliferation and invasion (p<0.05). Levels of NLRP3, interleukin-1ß (IL-1ß), matrix metalloproteinase-9 (MMP-9), MMP-2, N-cadherin, and vimentin were significantly reduced after miR-22 mimic transfection (p<0.05). Furthermore, silencing of NLRP3, a downstream gene of miR-22 in HCT116 cells, suppressed proliferation, migration, and invasion of HCT116 cells. However, overexpression of NLRP3 weakened the effects of the miR-22 mimic. In vivo, overexpression of miR-22 slowed the growth rate of tumors and reduced Ki-67 expression in tumor tissues compared with the model group (p<0.05). In tumor tissues, overexpression of miR-22 also decreased expression of NLRP3, IL-1ß, MMP-9, MMP-2, N-cadherin, and vimentin compared with the model group (p<0.05). Overexpression of NLRP3 weakened the role of miR-22 overexpression in vivo. CONCLUSION: miR-22 suppresses cell proliferation, migration, and invasion in colorectal cancer by targeting NLRP3.

H3K27 acetylation-induced lncRNA EIF3J-AS1 improved proliferation and impeded apoptosis of colorectal cancer through miR-3163/YAP1 axis.

Long noncoding RNAs (lncRNAs) are found to be aberrantly expressed and pose significant impacts in colorectal cancer (CRC), the most prevalent type malignancy in the gastrointestinal tract. This study aimed to find out the regulation of lncRNA EIF3J antisense RNA 1 (EIF3J-AS1) on CRC progression. Expressions of EIF3J-AS1, microRNA-3163 (miR-3163), and Yes-associated protein 1 (YAP1) in tissues and cells were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Association of EIF3J-AS1 with CRC prognosis was analyzed through the online bioinformatics tool GEPIA. The biological function of EIF3J-AS1 in CRC was investigated by Cell Counting Kit-8, colony formation, caspase-3 activity, and TUNEL staining. Competitive endogenous RNA (ceRNA) network of EIF3J-AS1/miR-3163/YAP1 was determined by luciferase reporter and RNA immunoprecipitation assays. Results showed that EIF3J-AS1 was upregulated in CRC tissues and cell lines, indicating poor prognosis of CRC patients. The silence of EIF3J-AS1 led to reduced proliferation and facilitated apoptosis of CRC cells. Mechanistcally, EIF3J-AS1 was upregulated by cAMP-response element-binding protein-binding protein-mediated histone H3 on lysine 27 acetylation (H3K27ac) at the promoter region, and EIF3J-AS1 upregulated YAP1 expression through sponging miR-3163 in CRC cells. In conclusion, we first found that H3K27 acetylation-induced lncRNA EIF3J-AS1 improved proliferation and impeded apoptosis of colorectal cancer through the miR-3163/YAP1 axis, which might potentially provide a novel molecular-targeted strategy for CRC treatment.

[Mechanism and prevention of urethral injury during transanal total mesorectal excision].

In recent years, transanal total mesorectal excision (taTME) has become one of the focuses of colorectal surgery, but it still faces some controversial problems that have not been solved, such as urethral injury as a typical complication. This paper, from the perspective of urological and rectal surgery respectively, elucidates the current research progress on the anatomy between the rectum and urethra. From the perspective of urethral anatomy, the main structure involving urethral injury in taTME surgery is the rectourethral muscle, which actually is part of the longitudinal muscle of the rectum from the perspective of rectal anatomy. Summarizing existing research results, the authors propose a new perspective about the key anatomical structure of hiatal ligament. As a matter of fact, hiatal ligament is the branch of longitudinal muscle of the rectum which circles the rectum, and the thickest part is at the center of the front and back respectively, then becomes thinner gradually to the 1 o'clock and 11 o'clock position. The front part of the hiatal ligament is just named as rectourethral muscle for urology surgery. On this basis, when taTME surgery is performed, it is recommended to follow the principle of " lateral first, center later" , that is, the thin lateral parts of hiatal ligaments is separated first, then the thick central parts after entering the familiar space. If necessary, the position of urethra and prostate can be confirmed through digital rectal examination, fluorescence catheter or other navigating methods. This paper aims to promote further development and popularization of taTME by introducing relevant anatomy of taTME surgery and various methods to avoid urethral injury.

Two-port laparoscopic anterior resection through a self-made glove device versus conventional laparoscopic anterior resection for rectal cancer: a comparison of short-term surgical results.

BACKGROUND: The laparoscopic approach has become increasingly incorporated into the development of new surgical procedures. An ever-increasing number of surgeons desire methods that minimize surgical trauma and provide improved cosmetic outcomes. Since 2014, we have performed two-port laparoscopic surgery using a transumbilical multichannel glove port and a 12-mm port. The aim of this study was to compare the short-term surgical results of two-port laparoscopic anterior resection (TPLAR) with those of conventional laparoscopic anterior resection (CLAR) for rectal cancer. METHODS: Between January 2014 and May 2014, a total of 27 patients underwent TPLAR and 30 patients underwent CLAR for the treatment of rectal cancer. The short-term surgical results of these two groups of patients were analyzed retrospectively. RESULTS: The differences in operative time, blood loss, conversion rate, complication rate, distal resection margin, number of harvested lymph nodes, duration until ambulation, duration until first flatus, length of postoperative hospital stay, and overall hospital costs between the two groups were not significant. The median (range) length of the abdominal incisions of the TPLAR patients was shorter than the length of the CLAR patients (5.1 (4.5-16.3) cm vs 8.2 (7.0-10.0) cm, respectively; p < 0.001). The respective median (range) postoperative pain scores were lower in the TPLAR than in the CLAR patients at 24 h (4 (1-6) h vs 5 (2-8) h; p = 0.045), 48 h (3 (1-4) h vs 4 (range 1-8) h; P = 0.004) and 72 h (1 (0-3) h vs 2 (1-5) h; p = 0.010). The median overall score on the satisfaction-with-abdominal-incision questionnaire of the TPLAR patients was significantly higher (better) than the score of the CLAR patients. CONCLUSIONS: TPLAR for rectal cancer is safe and feasible, with short-term perioperative and oncological outcomes similar to those of CLAR. TPLAR provides less postoperative pain and better cosmetic outcomes.

Laparoscopic Low Anterior Resection of the Rectum with Transanal Prolapsing Specimen Extraction: Early Experience with 23 Patients.

OBJECTIVE: For laparoscopic low anterior resection of the rectum, a small additional incision is needed to extract the specimen. We describe an adjustment technique, which inserted the anvil and extracted the specimen through transanal pathway. METHODS: Between July 2010 and July 2012, 23 patients underwent laparoscopic rectal surgery with transanal anvil insertion and transanal prolapsing specimen extraction. All perioperative data and short-term outcomes were recorded in a database. RESULTS: The mean patient age was 61.3 years (range 47-68 years). Of the 23 patients, 17 underwent resection for rectal carcinoma and 6 had tubulovillous adenomas. No intraoperative complications occurred. The mean operative time was 137 minutes (range 118-170 minutes). The distal margins, circumferential resection margins, and lymph node dissections were oncologically adequate for all malignancies. One patient experienced anastomotic leakage (4.3%), treated conservatively. One male patient with benign prostatic hyperplasia suffered from postoperative urinary retention. The average postoperative hospital stay was 11.3 days (range 7-21 days). No patients experienced anal dysfunction. At a median follow-up of 26 months, there were no tumor recurrences. CONCLUSION: The technique of transanal prolapsing specimen extraction for laparoscopic low anterior resection of the rectum is feasible and safe for selected patients.

[Expression and significance of RECK, metalloproteinase-9 and vascular endothelial growth factor-C in colorectal cancer].

OBJECTIVE: To investigate the expression of reversion-inducing cysteine-rich protein with Kazal motifs (RECK), matrix metalloproteinase-9 (MMP-9), and vascular endothelial growth factor-C (VEGF-C) in colorectal cancer. METHODS: S-P immunohistochemistry was used to detect the expression of RECK, MMP-9 and VEGF-C in colorectal cancer specimen. Colorectal mucosal tissue at least 10 cm away from the tumor was used as control. RESULTS: The positive expression of RECK in colorectal cancer was significantly lower than that in the controls(53.3% vs. 100%, P<0.05). Both MMP-9 and VEGF-C were over expressed compared with the controls(86.7% vs. 23.3% and 71.7% vs. 13.3% respectively, P<0.01). The expression of RECK was negatively correlated with that of MMP-9 and VEGF-C, and the expression of MMP-9 was positively correlated with that of VEGF-C. There were significant associations between the expression of these proteins and lymph node metastasis, distant metastasis, and TNM staging (all P<0.05). CONCLUSIONS: RECK expression is low in colorectal cancer, while MMP-9 and VEGF-C expressions are high. Combined testing of these 3 markers is important in the evaluation of tumor metastasis and invasion, and is helpful in the prediction of the prognosis.

Ileum perforation due to delayed operation in obturator hernia: a case report and review of literatures.

A 83-year-old woman was admitted to our hospital because of intermittent abdominal colicky pain and vomiting for 26 h. The pain localized over the periumbilical area with radiation along the medial side of the thigh. Computed tomography scan with three-dimensional reconstruction revealed a loop of small bowel protruding into the left obturator canal. Incarcerated obturator hernia was diagnosed and emergency laparotomy was arranged immediately. Unfortunately, her family refused surgery because of her worsening condition. On the third evening after admission, the patient developed peritonitis and sepsis. Perforation of small bowel due to the incarceration was noted during laparotomy. Bowel resection and an end-ileostomy were performed. She recovered well despite of the complication of multiple organ dysfunction syndrome. Literature is reviewed, and the pathogenesis, clinical manifestation, imaging features and treatment are discussed.

Clinicopathological characteristics of advanced colorectal cancer 30 mm or smaller in diameter.

OBJECTIVE: To investigate the clinicopathological characteristics of advanced colorectal cancer which was 30 mm or smaller in diameter. METHODS: Retrospective analysis documented 80 patients with small advanced colorectal cancer from May 1985 to May 2002. According to the diameter of tumors, all patients were divided into three groups: Group A (10 mm or less), Group B (11-20 mm), Group C (21-30 mm). Considering the number of patients in Group A was smaller, we combined Group A with Group B as Group D. Then various clinicopathological characteristics were compared between Group C and Group D. RESULTS: The most common site of small advanced colorectal cancer was sigmoid colon and rectum that accounted for 36.2% and 35.0% of all cases. The average diameter of total tumors was 23.3 mm. Type 2 was the most common macroscopic type (63.7%) and the moderate differentiation was seen in 77.5% of cases. Thirty-eight (47.5%) cases had lymph node metastasis. Three (3.8%) cases had liver metastasis and three (3.8%) cases had peritoneal metastasis. The frequency of lymph node metastasis was found significantly different between Group C and Group D (54.2% vs. 28.6%, P < 0.05) , as well as between the groups with different depth of invasion (P < 0.05). Curability A resection was performed in 69 (86.2%) cases. CONCLUSIONS: Tumor size and depth of invasion are related to lymph node metastasis in small advanced colorectal cancer. However, the small size of tumor may not always be a reliable parameter for estimating the risk of lymph node metastasis. Small colorectal cancers also do not always mean the early stage. Surgeons should be aware of the features of small advanced colorectal cancers to select ideal management and perform perfect resection.

Submucous colon lipoma: a case report and review of the literature.

Colon lipoma is remarkably rare in clinical practice. We reported a case of ascending colon lipoma in an 83-year-old woman. She was asymptomatic with a lipoma of 35 mm x 30 mm x 24 mm in size which was found by routine colonoscopy. Right hemicolectomy was performed uneventfully. The diagnosis was made by histological examination. Reviewing the literature and combining with our experience, we discussed the clinical features, diagnosis and treatment of this uncommon disease.