Abstract:Background and Aims: In recent years, more and more studies have found that the preservation of left colonic artery (LCA) in laparoscopic radical resection of rectal cancer can ensure the blood supply of the proximal bowel and reduce the incidence of anastomotic leakage. However, there are several variations in the branches of the inferior mesenteric artery (IMA), the D3 lymph node dissection with LCA preservation will increase the operation difficulty and significantly prolong the operative time. This study was conducted to investigate the feasibility and safety of low ligation with LCA-preserving D3 lymph node dissection under the guidance of preoperative CT angiography (CTA).  
Methods: The clinical data of 50 patients with rectal cancer undergoing laparoscopic anterior resection with low IMA ligation and D3 lymph node dissection from January 2018 to December 2019 in the Department of Gastroenterology of the Third Affiliated Hospital of Anhui Medical University were retrospectively analyzed. All patients underwent preoperative CTA three-dimensional reconstruction of the lower abdominal vessels for identifying the types of branch vessels of the IMA.
Results: Of the 50 patients, the proportions of type I, II, III and IV of IMA branches were 48.0% (24/50), 16.0% (8/50), 34.0% (17/50), and 2.0% (1/50), respectively. The length of IMA was 1.6-4.8 cm, with an average of (3.7±0.5) cm. the incidence of Riolan artery arcade absence was 70.0% (35/50). The operation was uneventfully completed in all patients, and no open conversion was required. The time for No.253 lymph node dissection was (18.5±5.8) min on average (ranged from 12-35 min), and the number of No.253 lymph node dissection was 4.5±1.3 on average (ranged from 0-6), in which, positive lymph nodes were identified in 2 cases (4.0%), and both of them were classified a pathological stage IIIC. The total operative time was (130±26) min on average (ranged from 115–190 min), the intraoperative blood loss was (65.8±7.8) mL on average (ranged from 30–150 mL), and the total number of lymph node dissection was 17.6±4.5 on average (range from 10–39). The histological classification of the 50 patients included highly differentiated adenocarcinoma in 10 cases, moderately differentiated adenocarcinoma in 25 cases, and poorly differentiated adenocarcinoma in 15 cases, and the pTNM stage included stage I in 5 cases, stage IIB in 23 cases, stage IIIA in 15 cases a, stage IIIB in 5 cases and stage IIIC in 2 cases. The length of postoperative hospital stay was (12.5±2.3) d on average (ranged from 8–15 d). No anastomotic leakage and other serious complications occurred in all patients after surgery, and one patient had dark red blood in stool after surgery, which was improved after hemostatic therapy. All patients were discharged from hospital after recovery. Followed-up was obtained in all patients for a period of 3–26 months. liver metastases occurred in one of the two patients with positive No.253 lymph node and stage IIIC disease at 14 months after surgery, and no death occurred in the entire group. 
Conclusion: For all rectal cancer patients, routine abdominal and pelvic CTA three-dimensional reconstruction is recommended before operation. Based on the types of branch vessels of the IMA, laparoscopic anterior rectal resection with accurate low ligation, LCA preservation and D3 lymphadenectomy is safe and feasible.

Abstract:Background and Aims: Total mesorectal excision (TME) is a standard technique for treatment of rectal cancer. Compared with open TME, laparoscopic-assisted TME (LaTME) has not only the advantage of minimal invasiveness, but also similar oncological outcomes. However, in obese, narrow-pelvis or male low rectal cancer patients, the pelvic operation of LaTME is still difficult, with increased risk of positive circumferential resection margin (CRM). The advent of laparoscopic-assisted transanal TME (TaTME) provides an innovative and minimally invasive option for low rectal cancer resection and provides new solutions for surgeons. This study was conducted to compare and analyze the clinical efficacy of laparoscopic-assisted TaTME and LaTME in treatment of low rectal cancer. 
Methods: The clinical data of 30 patients with low rectal cancer (the distance between inferior margin of tumor and anal verge ≤5 cm) treated in the Department of Gastrointestinal Surgery, Guangdong Provincial Hospital of Traditional Chinese Medicine from July 2018 to January 2019 were retrospectively analyzed. Of the patients, 12 cases underwent laparoscopic assisted TaTME (TaTME group), and 18 cases underwent LaTME (LaTME group). The main clinical variables were compared between the two groups of patients.
Results: There were no significant differences between the two groups of patients in terms of general data such as age, sex, BMI, ASA grade, oncological stage, distance from the inferior margin of the tumor to the anus, and tumor diameter (all P>0.05). No open conversion required and no early death occurred in both groups. The operative time of TaTME group was significantly shorter and the intraoperative blood loss was significantly less than those of LaTME group (168.5 min vs. 239.33 min, P=0.007; 66.50 mL vs. 160.00 mL, P=0.002), and no significant differences were noted with regard to preventive ileostomy, anus preservation rate, CRM-positive rate and total lymph node dissection (all P>0.05). The length of hospital stay of TaTME group was significantly shortened and the hospitalization cost was significantly reduced in TaTME group compared with LaTME group (6.33 d vs. 10.83 d, P<0.001; 58 963 yuan vs. 81 341 yuan, P<0.001), and the time to postoperative anal gas passage and time to whole liquid diet in TaTME group were all shortened compared with LaTME group, but the differences did not reach statistical significance (both P>0.05). The incidence rates of postoperative complications showed no significant difference between the two groups (P>0.05).
Conclusion: Laparoscopic-assisted TaTME has a similar short-term efficacy as laTME in treatment of low rectal cancer, and also offers advantages in certain respects. It is safe and feasible, and it is worthy of further exploration and application.

Abstract:Background and Aims: Primary anorectal small-cell carcinoma (SCC) is a rare type of cancer, accounting for less than 1% of all anorectal tumors. Compared with common anorectal adenocarcinoma, the clinical symptoms and imaging manifestations of anorectal SCC are not specific, so the diagnosis is difficult, postoperative recurrence and distant metastasis are easy to occur, the prognosis is poor, and the overall mortality is extremely high. Due to the rarity and particularity of anorectal SCC, there are so far few domestic and foreign literature reports available, lack of relevant research data and treatment experience as well as in-depth understanding of its characteristics, and no unified optimal treatment plan, which bring certain troubles to clinical diagnosis and treatment. Here, the authors discuss the diagnosis and treatment modality of anorectal SCC through analyzing the diagnosis and treatment process in a treated case of primary anorectal SCC, so as to provide corresponding clinical experience and new ideas for the diagnosis and treatment of this condition.  
Methods: The clinical data of one patient with primary anorectal SCC were retrospectively analyzed. The patient's medical history, general condition, imaging examination, pathological tissue morphology and characteristics of immunomarker were analyzed and diagnosed, and corresponding treatment strategies were developed according to its characteristics, combined with review of relevant literature.
Results: The clinical feature of the patient presented was bloody stool, which was considered as anorectal malignant tumor after imaging examination, and SCC was pathologically suggested after twice colonoscopic biopsies. Then, laparoscopic-assisted Miles surgery was performed, and postoperative pathologic diagnosis was SCC of the anorectal canal. After operation, additional comprehensive treatment compromising pelvic radiotherapy and "cisplatin plus etoposide" EP chemotherapy regimen was applied. Regular reexaminations such as chest CT, total abdominal CT, pelvic MRI, colonoscopy, serum tumor markers showed no tumor recurrence or distant metastasis. The patient has survived with tumor-free status for 13 months by now, and was still in follow-up observation.
Conclusion: Primary anorectal SCC is a rare disease with low overall survival. The clinical symptoms and imaging manifestations of anorectal SCC are similar to those of common anorectal adenocarcinoma without specificity. Biopsy material is difficult to obtain under colonoscopy, and the diagnosis requires combining the histopathological findings and a variety of immunohistochemical markers. Surgical resection is the most important and effective method for the treatment of locally advanced anorectal SCC. Surgical treatment should be carried out as soon as possible. Postoperative combined treatment with pelvic radiotherapy and "cisplatin plus etoposide" EP chemotherapy regimen can improve the prognosis of patients and prolong their survival time.

Abstract:Background and Aims: Neoadjuvant chemoradiotherapy (nCRT) is the gold standard for the treatment of mid-low locally advanced rectal cancer. Patients achieving pathologic complete remission (pCR) may have a better long-term prognosis. Despite the development of new molecular biology and progress of diagnosis and treatment technologies, there are few potential biomarkers for predicting good pathologic response before nCRT. This study was conducted to investigate the expression of mismatch repair (MMR) proteins in patients with mid-low locally advanced rectal cancer and their relationship with the sensitivity of nCRT.  
Methods: A total of 162 patients with mid-low locally advanced rectal cancer admitted in Gastrointestinal Surgery Department of Tongling People's Hospital from January 2014 to December 2019 were enrolled. All patients underwent surgery following nCRT. The expressions of MMR proteins (MLH1, MSH2, MSH6 and PMS2) in their initial colonoscopic biopsy samples were detected by immunohistochemical staining. The relations of MMR protein expression status with clinical variables and nCRT efficacy [according to the RECIST 1.1 evaluation criteria and tumor regressive grading (TRG) score], as well as the relations of the TRG score with the clinicopathologic factors and MMR protein expression status were analyzed, and the influential factors for pCR were determined by multivariate Logistic regression model.
Results: In the 162 patients, deficient MMR (dMMR) was found in 22 cases (13.4%), including MLH1 protein deletion in 17 cases (10.5%), MSH2 protein deletion in 10 cases (6.2%), MSH6 protein deletion in 8 cases (4.9%) and PMS2 protein deletion in 11 cases (6.8%). Histological type, preoperative clinical stage and TRG score were significantly associated with MMR protein expression status (all P<0.05). The effective rate assessed by RECIST 1.1 in dMMR patients was higher than that in patients with proficient MMR (pMMR) (59.1% vs. 36.4%, P=0.043). The sex age, tumor location, differentiation, histological type, CEA level, synchronous chemotherapy regimen and expressions of MLH1, MSH2, MSH6 and PMS2 proteins were irrelevant to TRG score (all P>0.05), while the clinical T stage, clinical N stage, preoperative clinical stage, and the MMR protein expression status (dMMR or pMMR) were related to TRG score (all P<0.05). Logistic multivariate regression analysis revealed that dMMR was an independent influential factor for pCR of the patients (OR=0.327, 95% CI=0.109–0.984, P=0.047). 
Conclusion: In patients with mid-low locally advanced rectal cancer, the dMMR protein phenotype presented in the tissue of initial colonoscopic biopsy indicates a better nCRT effect, and MMR protein expression status can be used as a predictor of nCRT efficacy for rectal cancer patients.

Abstract:Background and Aims: Long non-coding RNAs (lncRNAs) exert significant influences on the prognosis of gastric cancer patients. This study was designated to construct a lncRNA-based prediction model for accurately evaluating the prognosis of gastric cancer patients through bioinformatics approaches. 
Methods: The data obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases were used for constructing the prognosis model (modeling group), while the data from The Gene Expression Omnibus (GEO) database were used for validation (validation group). The differentially expressed lncRNAs were screened using edgeR package in R software. Univariate and multivariate Cox regression were used to evaluate the association between LncRNA and survival time. prognostic model was created through univariate and multivariate Cox regression analyses and the risk score were calculated. The patients were divided into high-risk group and low-risk group according to their risk scores, and the relations of the risk score with clinicopathologic variables and prognosis were analyzed. The results of the modeling group were verified in the sample from validation group.
Results: A total of 288 differentially expressed lncRNAs were screened, and 28 of them were associated with the prognosis of gastric cancer (all P<0.05). Ten lncRNA biomarkers (MEG3, DNAJC9-AS1, ACTA2-AS1, C15orf54, LINC01210, OVAAL, POU6F2-AS2, ERICH3-AS1, LINC00326 and LINC01526) were identified and used to construct a prognostic model. Both overall survival rate and disease-free survival rate in high-risk group were significantly lower than those in low-risk group (both P<0.01). ROC curve confirmed that the prediction model had certain accuracy (AUC=0.700). The results of univariate and multivariate Cox regression analyses showed that the risk score was an independent prognostic factor (both P<0.001). The risk score had significant relation with T stage (P=0.031) and the degree of tumor differentiation (P=0.044). In validation cohort, the overall survival rate and disease-free survival rate in high-risk group were also lower than those in low-risk group, and the risk score remained an independent prognostic factor (all P<0.05). 
Conclusion: The constructed 10-lncRNA model has certain value in predicting the prognosis of gastric cancer patients, and the screened differentially expressed lncRNAs also provide the basis for further investigating the molecular mechanism of gastric cancer.

Abstract:Background and Aims: Although the treatment of colorectal cancer has been increasingly improved, the current treatment efficacy remains unsatisfactory. Therefore, the consistent screening and identification of the critical molecules that play the regulatory roles in the initiation and progression of colorectal cancer along with revelation of their functions and actions is an important process to develop new diagnostic and therapeutic targets and eventually improve the treatment effect of colorectal cancer. Accordingly, this study was designated for the first time to investigate the expression level of carboxyl ester lipase (CEL) in colorectal cancer, and preliminarily analyze its biological function in colorectal cancer. 
Methods: Based on the UALCAN and GEPIA online databases containing cancer gene expression data, the expression of CEL and its promoter methylation status in colorectal cancer and normal tissues were analyzed. Then, the expression of CEL in colorectal cancer tissue/tumor adjacent normal tissue and colorectal cancer cell lines/normal human colonic epithelial cells were further determined by qPCR, immunohistochemical staining and Western blot, respectively. The expression level of CEL in human colorectal cancer SW620 cells was transiently knocked down by transfection with siRNA specifically targeting CEL (siCEL), after that, the primary biological functions of CEL in colorectal cancer were analyzed by CCK-8 assay, plate colony formation assay, Transwell migration and invasion assay, respectively. 
Results: The data from cancer-relevant databases showed that the expression of CEL in colorectal cancer tissues was significantly higher than that in normal tissues (P<0.05, P<0.001), and the promoter methylation level of CEL in colorectal cancer tissues was significantly lower than that in normal tissues (P<0.001). The results of qPCR, immunohistochemical staining and Western blot further confirmed that the gene and protein expression levels of CEL in colorectal cancer tissue were significantly higher than those in control tissue, and in colorectal cancer cells were significantly higher than those in normal colonic epithelial cells (P<0.01, P<0.001). In SW620 cells after CEL expression knock-down by siCEL transfection, the growth speed, colony?forming ability, as well as the migration and invasion abilities were all significantly inhibited (P<0.05, P<0.01, P<0.001). 
Conclusion: CEL expression is upregulated in colorectal cancer, which may be related to its hypomethylated promoter. The malignant biological behaviors of colorectal cancer cells can be inhibited by CEL knock-down, suggesting that high CEL expression promotes malignant progression of colorectal cancer. So, CEL may be a potential target for diagnosis and treatment of colorectal cancer.

Abstract:Background and Aims: Laparoscopic radical gastrectomy has become the first choice for surgical treatment of gastric cancer. The surgical procedure mainly comprises radical resection of the tumor and digestive tract reconstruction. Digestive tract reconstruction is a difficult technique during the operation, and especially, the totally laparoscopic esophagojejunostomy is the most difficult procedure to perform, which greatly restricts the clinical development of totally laparoscopic radical total gastrectomy. The π-shaped esophagojejunostomy is a linear anastomosis technique based on a linear cutting closure device, which is reported to simplify the procedure and shorten the operative time. Therefore, this study was conducted to evaluate the application value of π-shaped esophagojejunostomy in totally laparoscopic radical total gastrectomy.  
Methods: The clinical data of 78 patients with gastric cancer treated in the Department of Gastrointestinal Surgery of Wuhu Second People's Hospital between January 2016 and January 2020 were retrospectively analyzed. All patients underwent total laparoscopic gastrectomy with D2 lymphadenectomy. Of the patients, 40 cases underwent π-shaped esophagojejunostomy (observation group) and 38 cases underwent traditional functional end-to-end esophagojejunostomy (control group) for digestive tract reconstruction. The main intra- and postoperative variables were compared between the two groups of patients. 
Results: Total gastrectomy, lymphadenectomy and digestive tract reconstruction were uneventfully completed in all patients under totally laparoscopic surgery, none required open conversion and all had a negative esophageal margin. In observation group compared with control group, the total operative time and the operative time for esophagojejunostomy were significantly shortened, and the intraoperative blood loss was significantly decreased (217.4 min vs. 237.9 min; 22.6 min vs. 34.8 min; 64.4 mL vs. 99.2 mL, all P<0.05); the time to first ambulation and the time to first flatus passage after the operation were all significantly shortened (1.5 d vs. 2.3 d; 2.6 d vs. 2.9 d, both P<0.05). Postoperative complications occurred in 3 patients in observation group and 2 patients in control group, and the incidence of postoperative complications had no significant difference between the two groups (P=0.687). There were no significant differences in terms of the length of postoperative hospital stay and the number of resected lymph nodes between the two groups (both P>0.05). Postoperative follow-up was conducted for 3 to 12 months, and the anastomotic stoma was patent in all patients. 
Conclusion: The application of π-shaped esophagojejunostomy is safe and feasible in totally laparoscopic radical total gastrectomy. Compared with the traditional functional end-to-end esophagojejunostomy, it has the advantages of shorter operative time and esophagojejunostomy time, and faster postoperative recovery. Its short-term efficacy is also satisfactory.

Abstract:Background and Aims: Gastric cancer, characterized by high degree of malignancy and early metastasis, often leads to poor clinical prognosis, and particularly the gastric cancer liver metastasis (GCLM) is the main cause of death of the patients. However, there are still certain deficiencies in the evaluation methods for the prognosis of patients with GCLM at present. Therefore, this study was conducted to establish a prognostic evaluation model with good predictive ability by analyzing the clinicopathologic characteristics and prognostic risk factors of patients with GCLM based on the SEER database, so as to improve the individualized prognostic evaluation ability for the patients. 
Methods: The clinical data of GCLM patients diagnosed from 2010 to 2015 were extracted from SEER database. According to the inclusion and exclusion criteria, a total of 2 554 patients were included in the study after strict screening, and then the patients were randomly assigned to modeling set (1 790 cases) and validation set (764 cases) with a 7:3 ratio. The clinical baseline characteristics of patients in modeling set and the validation set were compared, and the independent risk factors for the overall survival (OS) and the cancer-specific survival (CSS) of GCLM patients were screened by Cox equal proportional regression model and Fine-Gray competitive risk model, respectively. Based on the results of multiple regression analysis of the modeling set Cox and Fine-Gray risk model and AIC optimization, the nomogram models for predicting the OS and CSS of GCLM patients were constructed. Finally, the reliability of the predictions obtained from the models were evaluated by C-index, ROC curve and calibration curve.
Results:  There were no significant difference in the baseline characteristic between the patients in modeling set and validation set. The results of analysis showed that age, chemotherapy, tumor grade, primary lesion resection and number of primary lesions were independent risk factors for OS, and chemotherapy, tumor grade, primary lesion resection and number of primary lesions were independent risk factors for CSS in GCLM patients. Based on the above variables, the nomogram models were constructed and evaluated, respectively. The C-index of either the nomogram model for predicting OS or for predicting CSS was remarkably higher than that of AJCC-TNM staging system (modeling set: 0.706 vs. 0.560 and 0.670 vs. 0.554; validation set: 0.769 vs. 0.534 and 0.744 vs. 0.518). Moreover, the ROC curve analysis showed that both prediction models had a relatively high accuracy. Finally, the calibration curve analysis showed that both nomogram models predicted OS or CSS had a good consistency with the actual observed values.
Conclusion: The constructed nomogram models based on SEER database have relatively high accuracy in predicting the OS and CSS in GCLM patients, which may help the clinicians to develop individualized treatment strategies for GCLM patients.

Abstract:Background and Aims: Bariatric-metabolic surgeries are effective treatment for severely obese patients with type 2 diabetes mellitus (T2DM). However, different types of bariatric-metabolic surgeries have different effects on aspects such as weight reduction and blood glucose control. Therefore, this study was conducted to investigate the short-term efficacy of different types of bariatric-metabolic surgeries for severely obese patients with T2DM, and their characteristics in terms of reducing weight, sugar and lipid, so as to provide treatment options for clinical use. 
Methods: The clinical data of 63 patients with severe obesity and concomitant T2DM undergoing bariatric-metabolic surgery were retrospectively analyzed. Of the patients, 25 cases underwent laparoscopic sleeve gastrectomy (LSG), 18 cases underwent LSG plus jejuno-jejunal bypass surgery (LSG+JJB), and 20 cases underwent laparoscopic Roux-en-Y gastric bypass surgery (LRYGB). The clinical data before surgery and 6 and 12 months after surgery among the three groups of patients were compared. 
Results: The preoperative data were comparable among the three groups. Operations were successfully completed in all patients. Among the three groups, the operative times were significantly different (P<0.05), but all other surgery-related variables showed no significant differences (all P>0.05). The weight loss variables that included the body weight, waist circumference, hip circumference, BMI and the percentage of excess weight loss (%EWL) in the three groups after surgery were significantly improved compared to those before surgery (all P<0.05), in which, the hip circumference showed no significant difference between postoperative 6 and 12 months in the same groups as well as among groups at the same time points (all P>0.05), while all the remaining 4 variables were significantly better at postoperative 12 months than those at 6 months in the same groups, and were significantly better in LSG+JJB group and LRYGB group than those in LSG group (all P<0.05), but showed no significant differences between LSG+JJB group and LRYGB group (all P>0.05). The indexes of glucose metabolism that included the fasting plasma glucose, fasting insulin, glycated hemoglobin, insulin resistance index in the three groups after surgery were significantly improved compared to those before surgery (all P<0.05), but there were no significant differences in these indexes between postoperative 6 and 12 months as well as among groups at the same time points (all P>0.05); the diabetes remission rates at 6 and 12 months after surgery showed no significant difference among the three groups (both P>0.05). The parameters of lipid metabolism that included the blood cholesterol, triglyceride, low-density lipoprotein, high-density lipoprotein and uric acid in the three groups after surgery were improved compared to those before surgery (all P<0.05), and the degrees of improvement in triglyceride, high-density lipoprotein, and low-density lipoprotein were similar in the three groups (all P>0.05), but the decreasing amplitudes in blood uric acid and cholesterol in LRYGB group and LSG+JJB group were significantly greater than those in LSG group (all P<0.05). 
Conclusion: All LSG, LSG+JJB and LRYGB have good short-term efficacy in reducing weight and improving glucose and lipid metabolism. They have similar effects of reducing blood glucose and some lipid parameters. LSG+JJB has the same effect as LRYGB and both are superior to LSG in reducing weight, uric acid and cholesterol. LSG+JJB is simple in operation with demonstrable efficacy. So, it is recommended to be used in clinical practice.

Abstract:Background and Aims: Aberrant right subclavian artery (ARSA) is one of the congenital anomalies of the aortic arch. Stanford type B aortic dissection (TBAD) combined with ARSA is extremely rare and life-threatening. Most of them previously were treated by means of conventional open surgery or hybrid operation. With the rapid development of endovascular techniques, thoracic endovascular aortic repair (TEVAR) is being increasingly used in the treatment of TBAD associated with ARSA, which has the advantages of minimal invasive and fast postoperative recovery. Due to the uncertainty of the relative locations of ARSA to the primary entry tear of the TBAD, how to deal with ARSA and primary entry tear must be taken into serious consideration. The efficacy and safety of total endovascular treatment of this complex condition of the aortic arch are uncertain. Therefore, this study was conduct to investigate endovascular repair for TBAD with ARSA, and provide the preliminary experience. 
Methods: The clinical data of 16 patients with TBAD and combined ARSA undergoing TEVAR in the Second Xiangya Hospital of Central South University from January 2012 to December 2019 were retrospectively analyzed. Of the patients, 14 cases were males and 2 cases were females, with an average age of (56±11.3) years; the primary entry tear located in zone 3 in 13 cases, and located in zone 4 in 3 cases; left vertebral artery dominance presented in 14 cases, right vertebral artery dominance was found in 1 case and 1 case had equipotent bilateral vertebral arteries. Personalized operative plans were made according to the locations of the primary entry tear and the opening of bilateral subclavian arteries as well as the pattern of the vertebral arteries.
Results: The technical success rate was 100%. The mean operative time was (95.2±38.9) min. There was no perioperative mortality. The blood flow of bilateral subclavian arteries was preserved in 3 patients, 5 cases underwent covering of the ARSA, chimney technique was used in 7 patients to preserve the left subclavian artery (LSA), both chimney and periscope techniques were used in one patient to reconstruct the ARSA, and fenestration technique was used in one patient to reconstruct the LSA. Patients undergoing reconstruction of the branches of the aortic arch were administered with aspirin (100 mg/d) and clopidogrel (75 mg/d) for 3 months after operation. The mean follow-up time was 33.2 (3–66) months. No endoleak or stent graft migration occurred; right upper limb ischemia occurred in 2 patients, which recovered gradually after conservative treatment; the comparison between preoperative CTA and the last follow-up CTA showed that the mean maximum diameter of the descending aorta was decreased from (37.1±9.6) mm to (33.9±8.9) mm, and the false/true lumen ratio was decreased from 1.03±0.62 to 0.21±0.31. During long-term follow-up, all of the chimney stent grafts were patent, and none of the patients developed symptoms such as ischemia of the branch arteries of the aortic arch, subclavian steal syndrome and spinal cord ischemia.
Conclusion: TEVAR combined with chimney or fenestration technique is safe and feasible for TBAD with ARSA, by which, the primary entry tear of the aortic dissection can be effectively covered with simultaneous preservation of the blood flow of the LSA and (or) ARSA, with the advantages of quick recovery, short of hospitalization and low incidence of perioperative complications. The specific operative procedure should be based on the relative locations of ARSA to the primary entry tear, and ensure at least the blood flow of the ipsilateral subclavian artery giving rise to the dominant vertebral artery.

Abstract:Lynch syndrome (LS) is an autosomal inherited disease caused by mutations in DNA mismatch repair (MMR) genes. LS-associated gastric cancer, its incidence ranking first among all LS-associated gastrointestinal tumors, is different from the gastric cancer in general population, and presents the pathological features of microsatellite instability (MSI) and being sensitive to immunotherapy. With the precision of LS molecular detection and the popularization of various diagnostic technologies, LS patients and their families have an increasing demand for LS-associated gastric cancer screening, surveillance, and treatment. However, but their strategies are still unclear, and there are still many controversies. The incidence risk of LS-associated gastric cancer is high in Asian population. China, as one of the Asian countries, should strengthen the identification of LS patients and standardize management measures. Here, the authors review the relevant literature concerning the LS-associated gastric cancer in recent years, so as to provide a basis and reference for fully understanding the LS-associated gastric cancer, optimizing its prevention decision, and improving its diagnosis and treatment.

Abstract:New cases of gastric cancer rank fifth in malignant tumors, while colorectal cancer is the third most common malignant tumor and the fourth most common cause of cancer death in the world. The dynamic balance of histone acetylation is jointly maintained by histone acetyltransferase (HAT) and histone deacetylase, (HDAC) enzyme families. HDAC can remove acetyl groups from lysine, thus inhibiting gene transcription. However, abnormally high expression of HDAC can induce normal cells to turn cancerous and participate in its development, proliferation, invasion and metastasis. Targeted inhibition of HDAC has been proved to have anti-tumor effect. Histone deacetylase inhibitors (HDACi) can inhibit the expression and activity of HDAC. Moreover, HDAC plays a potent anti-tumor role by influencing the level of cell reactive oxygen species, blocking cell cycle, promoting repair of damaged DNA, resisting angiogenesis, influencing cell signal pathways, inducing autophagy apoptosis and increasing the sensitivity of cells to chemoradiotherapy drugs. HDAC expression is increased in gastric cancer and colorectal cancer, and HDACi also shows good results in the study of gastrointestinal tumors. Since the catalytic core functions of class I, II and IV HDAC all depend on Zn2+, most HDACi contain Zn2+ chelating groups. SAHA and TSA in hydroxamic acid inhibitors have good anti-tumor effects when administered alone in small doses. However, later clinical studies found that SAHA has poor clinical efficacy in treating gastric cancer and colorectal cancer due to its low activity. The activity of TSA has been improved, but its selectivity to HDAC is still low, benzamide HDACi is improved in selectivity, but it cannot be only targeted at specific subtypes of HDAC. The selectivity of late cyclic peptides and newly reported HDACi is gradually increased, but it is only limited to animal and cell experimental stages, and the above-mentioned HDACi can combine with other metalloenzymes in addition to Zn2+, thus lacking absolute specificity. Therefore, most HDACi has caused side effects at a very small dose. As the occurrence and development of tumors involve multiple steps and factors, a single target often cannot effectively kill cancer cells and is prone to drug resistance. Combination of multiple targets has stronger anti-cancer effect than a single target, and can even reduce the occurrence of drug resistance. However, sometimes adverse reactions caused by drug interaction may occur when drugs are used in combination. In order to avoid drug interaction, based on the concept of pharmacophore splicing, researchers designed and synthesized a new multitarget inhibitor by reasonably splicing HDACi active groups and active groups of other drugs with different action targets. Studies have proved that multi-target inhibitors not only avoid drug interactions, but also improve drug effects. This paper introduces in turn the research progress of HDACi and HDACi-related multi-inhibitors in gastrointestinal tumors.

Abstract:The intestinal tract is not only an important place for digestion and absorption of the human body, but also the largest immune organ, which plays an important role in maintaining normal immune defense and other functions of the body. The survival and reproduction of intestinal microorganisms depends on the special micro-ecological environment in the intestinal tract, and they can also complete a variety of metabolic functions that the human body does not possess. Intestinal microorganisms have a great influence on the occurrence and development of human diseases, in which the bacteria in the intestinal tract constitutes the largest proportion with a number more than 100 trillion, directly or indirectly participates in the processes of immune regulation, substance metabolism, digestion and absorption in the human body, and plays an important role in the protection of intestinal mucosa, the maintenance of intestinal homeostasis and the normal function of the body, as well as disease resistance. The microflora colonized in the intestinal tract are closely related, are always relatively independent but interrelated, and their populations and numbers maintain a dynamic balance. Treatments such as surgery, radiotherapy, chemotherapy and fasting, mechanical intestinal preparation or the use of antibiotics can change its composition and function, thus affecting the dynamic balance of gut microbiota, and even lead to flora imbalance. Studies have found that gut microbiota imbalance can directly or indirectly affect the occurrence and development of colorectal cancer through immunomodulatory and inflammatory reactions, genotoxic reactions, metabolites and so on. In recent years, the role of gut microbiota in non-invasive diagnosis, radiotherapy, chemotherapy and immunotherapy of colorectal cancer has been gradually confirmed. In addition, the intake of probiotics and other microbial products through diet regulation and fecal therapy also provide a new idea for the prevention and treatment of colorectal cancer and the related complications. A comprehensive understanding of the relationship between gut microbiota and colorectal cancer can provide a theoretical basis for the biological prevention and treatment of colorectal tumors. Based on the above background, the authors address the relationship between gut microbiota and colorectal neoplasm through reviewing the relevant literature in recent years.