Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms

This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the analysis.The diagnosis and depth assessment of EUS was compared to the histology findings.The prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior specificity.EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision.

GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms:A Chinese multicenter study of 12-year experience

BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)using data from a large cohort.METHODS Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in China.Random forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival,and two nomograms were constructed.RESULTS A total of 1408 patients with R-NENs were included.Tumor grade,T stage,tumor size,age,and a prognostic nutritional index were important risk factors for prognosis.The GATIS score was calculated based on these five indicators.For overall survival prediction,the respective C-indexes in the training set were 0.915(95%confidence interval:0.866-0.964)for overall survival prediction and 0.908(95%confidence interval:0.872-0.944)for progression-free survival prediction.According to decision curve analysis,net benefit of the GATIS score was higher than that of a single factor.The time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time periods.CONCLUSION The GATIS score had a good predictive effect on the prognosis of patients with R-NENs,with efficacy superior to that of the World Health Organization grade and TNM stage.

Feasibility and safety of minimally invasive multivisceral resection for T4b rectal cancer:A 9-year review

BACKGROUND Colorectal cancer is the third most common cancer and the second highest cause of cancer-related mortality worldwide.About 5%-10%of patients are diagnosed with locally advanced rectal cancer(LARC)on presentation.For LARC invading into other structures(i.e.T4b),multivisceral resection(MVR)and/or pelvic ex-enteration(PE)remains the only potential curative surgical treatment.MVR and/or PE is a major and complex surgery with high post-operative morbidity.Minimally invasive surgery(MIS)has been shown to improve short-term post-operative outcomes in other gastrointestinal malignancies,but there is little evi-dence on its use in MVR,especially so for robotic MVR.This is a single-center retrospective cohort study from 1st January 2015 to 31st March 2023.Inclusion criteria were patients diagnosed with cT4b rectal cancer and underwent MVR,or stage 4 disease with resectable systemic metastases.Pa-tients who underwent curative MVR for locally recurrent rectal cancer,or me-tachronous rectal cancer were also included.Exclusion criteria were patients with systemic metastases with non-resectable disease.All patients planned for elective surgery were enrolled into the standard enhanced recovery after surgery pathway with standard peri-operative management for colorectal surgery.Complex sur-gery was defined based on technical difficulty of surgery(i.e.total PE,bladder-sparing prostatectomy,pelvic lymph node dissection or need for flap creation).Our primary outcomes were the margin status,and complication rates.Cate-gorical values were described as percentages and analysed by the chi-square test.Continuous variables were expressed as median(range)and analysed by Mann-Whitney U test.Cumulative overall survival(OS)and recurrence-free survival(RFS)were analysed using Kaplan-Meier estimates with life table analysis.Log-rank test was performed to determine statistical significance between cumulative estimates.Statistical significance was defined as P<0.05.Meier estimates with life table analysis.Log-rank test was performed to determine statistical significance between cumulative estimates.Statistical significance was defined as P<0.05.RESULTS A total of 46 patients were included in this study[open MVR(oMVR):12(26.1%),miMVR:36(73.9%)].Patients’American Society of Anesthesiologists score,body mass index and co-morbidities were comparable between oMVR and miMVR.There is an increasing trend towards robotic MVR from 2015 to 2023.MiMVR was associated with lower estimated blood loss(EBL)(median 450 vs 1200 mL,P=0.008),major morbidity(14.7%vs 50.0%,P=0.014),post-operative intra-abdominal collections(11.8%vs 50.0%,P=0.006),post-operative ileus(32.4%vs 66.7%,P=0.04)and surgical site infection(11.8%vs 50.0%,P=0.006)compared with oMVR.Length of stay was also shorter for miMVR compared with oMVR(median 10 vs 30 d,P=0.001).Oncological outcomes-R0 resection,recurrence,OS and RFS were comparable between miMVR and oMVR.There was no 30-d mortality.More patients underwent robotic compared with laparoscopic MVR for complex cases(robotic 57.1%vs laparoscopic 7.7%,P=0.004).The operating time was longer for robotic compared with laparoscopic MVR[robotic:602(400-900)min,laparoscopic:Median 455(275-675)min,P<0.001].Incidence of R0 resection was similar(laparoscopic:84.6%vs robotic:76.2%,P=0.555).Overall complication rates,major morbidity rates and 30-d readmission rates were similar between la-paroscopic and robotic MVR.Interestingly,3-year OS(robotic 83.1%vs 58.6%,P=0.008)and RFS(robotic 72.9%vs 34.3%,P=0.002)was superior for robotic compared with laparoscopic MVR.CONCLUSION MiMVR had lower post-operative complications compared to oMVR.Robotic MVR was also safe,with acceptable post-operative complication rates.Prospective studies should be conducted to compare short-term and long-term outcomes between robotic vs laparoscopic MVR.

Transanal Endoscopic Microsurgery (TEM) for Rectal Neoplasms

Introduction: The abdominal approach for the treatment of rectal tumors is associated with a considerable rate of morbidity. Transanal Endoscopic Microsurgery (TEM) is an alternative technique that is less invasive than radical surgery, and therefore has a lower associated morbidity. Moreover, with proper patient selection, TEM presents oncological outcomes comparable to radical surgery. The aim of this study is to review our results obtained with TEM and discuss its role in the treatment of malignant rectal lesions. Patients and Methods: A prospective descriptive study from June 2008 until February 2011. The indications for TEM were: early rectal neoplastic lesions (T1N0M0) with good prognostic factors;neoplastic lesions in more advanced stages in selected patients (high surgical risk, refusal of radical surgery or stoma, and palliative intention). Results: Resection by TEM was performed on 19 patients. The average hospital stay was 5.7 days with an associated morbidity of 16.7%. R0 resection was 88.8%. During the follow-up of 15 (3 - 31) months, no recurrence has been shown. Conclusions: TEM is a safe and effective procedure for the treatment of selected early malignant rectal lesions and is associated with low morbidity. It is a therapeutic strategy based on a multidisciplinary team, careful patient selection, an audited surgical technique and a strict follow-up protocol.

Impact of technology on indications and limitations for transanal surgical removal of rectal neoplasms

Transanal surgery has and continues to be well accepted for local excision of benign rectal disease not amenable to endoscopic resection. More recently, there has been increasing interest in applying transanal surgery to local resection of early malignant disease. In addition, some groups have started utilizing a transanal route in order to accomplish total mesorectal excision(TME) for more advanced rectal malignancies. We aim to review the role of various transanal and endoscopic techniquesin the local resection of benign and malignant rectal disease based on published trial data. Preliminary data on the use of transanal platforms to accomplish TME will also be highlighted. For endoscopically unresectable rectal adenomas, transanal surgery remains a widely accepted method with minimal morbidity that avoids the downsides of a major abdomino-pelvic operation. Transanal endoscopic microsurgery and transanal minimally invasive surgery offer improved visualization and magnification, allowing for finer and more precise dissection of more proximal and larger rectal lesions without compromising patient outcome. Some studies have demonstrated efficacy in utilizing transanal platforms in the surgical management of early rectal malignancies in selected patients. There is an overall higher recurrence rate with transanal surgery with the concern that neither chemoradiation nor salvage surgery may compensate for previous approach and correct the inferior outcome. Application of transanal platforms to accomplish transanal TME in a natural orifice fashion are still in their infancy and currently should be considered experimental. The current data demonstrate that transanal surgery remains an excellent option in the surgical management of benign rectal disease. However, care should be used when selecting patients with malignant disease. The application of transanal platforms continues to evolve. While the new uses of transanal platforms in TME for more advanced rectal malignancy are exciting, it is important to remain cognizant and not sacrifice long term survival for short term decrease in morbidity and improved cosmesis.

Different oncological features of colorectal cancer codon-specific KRAS mutations:Not codon 13 but codon 12 have prognostic value

BACKGROUND Approximately 40%of colorectal cancer(CRC)cases are linked to Kirsten rat sarcoma viral oncogene homolog(KRAS)mutations.KRAS mutations are associated with poor CRC prognosis,especially KRAS codon 12 mutation,which is associated with metastasis and poorer survival.However,the clinicopathological characteristics and prognosis of KRAS codon 13 mutation in CRC remain unclear.AIM To evaluate the clinicopathological characteristics and prognostic value of codonspecific KRAS mutations,especially in codon 13.METHODS This retrospective,single-center,observational cohort study included patients who underwent surgery for stage I-III CRC between January 2009 and December 2019.Patients with KRAS mutation status confirmed by molecular pathology reports were included.The relationships between clinicopathological characteristics and individual codon-specific KRAS mutations were analyzed.Survival data were analyzed to identify codon-specific KRAS mutations as recurrence-related factors using the Cox proportional hazards regression model.RESULTS Among the 2203 patients,the incidence of KRAS codons 12,13,and 61 mutations was 27.7%,9.1%,and 1.3%,respectively.Both KARS codons 12 and 13 mutations showed a tendency to be associated with clinical characteristics,but only codon 12 was associated with pathological features,such as stage of primary tumor(T stage),lymph node involvement(N stage),vascular invasion,perineural invasion,tumor size,and microsatellite instability.KRAS codon 13 mutation showed no associations(77.2%vs 85.3%,P=0.159),whereas codon 12 was associated with a lower 5-year recurrence-free survival rate(78.9%vs 75.5%,P=0.025).In multivariable analysis,along with T and N stages and vascular and perineural invasion,only codon 12(hazard ratio:1.399;95%confidence interval:1.034-1.894;P=0.030)among KRAS mutations was an independent risk factor for recurrence.CONCLUSION This study provides evidence that KRAS codon 13 mutation is less likely to serve as a prognostic biomarker than codon 12 mutation for CRC in a large-scale cohort.

Genetic polymorphisms in genes regulating cell death and prognosis of patients with rectal cancer receiving postoperative chemoradiotherapy

Objective:The identification of biomarkers for predicting chemoradiotherapy efficacy is essential to optimize personalized treatment.This study determined the effects of genetic variations in genes involved in apoptosis,pyroptosis,and ferroptosis on the prognosis of patients with locally advanced rectal cancer receiving postoperative chemoradiotherapy(CRT).Methods:The Sequenom MassARRAY was used to detect 217 genetic variations in 40 genes from 300 patients with rectal cancer who received postoperative CRT.The associations between genetic variations and overall survival(OS)were evaluated using hazard ratios(HRs)and 95%confidence intervals(CIs)computed using a Cox proportional regression model.Functional experiments were performed to determine the functions of the arachidonate 5-lipoxygenase(ALOX5)gene and the ALOX5 rs702365 variant.Results:We detected 16 genetic polymorphisms in CASP3,CASP7,TRAILR2,GSDME,CASP4,HO-1,ALOX5,GPX4,and NRF2 that were significantly associated with OS in the additive model(P<0.05).There was a substantial cumulative effect of three genetic polymorphisms(CASP4 rs571407,ALOX5 rs2242332,and HO-1 rs17883419)on OS.Genetic variations in the CASP4 and ALOX5 gene haplotypes were associated with a higher OS.We demonstrated,for the first time,that rs702365[G]>[C]represses ALOX5 transcription and corollary experiments suggested that ALOX5 may promote colon cancer cell growth by mediating an inflammatory response.Conclusions:Polymorphisms in genes regulating cell death may play essential roles in the prognosis of patients with rectal cancer who are treated with postoperative CRT and may serve as potential genetic biomarkers for individualized treatment.

External validation of the Moroccan Arabic version of the European Organization for Research and Treatment of Cancer colorectal(CR29)module:Monocentric study

BACKGROUND Quality of life(QoL)outcomes are a focal endpoint of cancer treatment strategies.AIM To externally validate the Moroccan Arabic version of the European Organization for Research and Treatment of Cancer(EORTC)QoL Questionnaire(QLQ)for colorectal cancer(CRC)patients(CR29).METHODS Both Moroccan Arabic modules of QLQ-CR29 and QLQ-C30 were administered to Moroccan CRC.Psychometric properties were retested by measuring Cronbach’s alpha coefficient for reliability and Intraclass correlation coefficient(ICC)to examine test-retest reproducibility.The multitrait-scaling analysis was performed to demonstrate the validity of the instrument and known-groups comparison was used to test the score’s ability to discriminate between different groups of patients.RESULTS In total,221 patients were included in our study and 34 patients completed the questionnaire twice.The Urinary Frequency scale and Stool Frequency scale had good internal consistency with alpha Cronbach coefficients of 0.79 and 0.83 respectively,while the same coefficients were moderately lower for the Blood and Mucus in Stool scale(0.61)and the Body Image scale(0.67).The ICCs ranged from 0.88 to 1 indicating good to excellent reproducibility.In multitrait scaling analyses,the criterion for item convergent and divergent validity was satisfactory.The known-group comparison showed statistically significant differences between patients according to age,gender,stoma status,tumor location,and radiotherapy.CONCLUSION The Moroccan Arabic version of the EORTC QLQ-CR29 is a valid and reliable tool that can be used safely for research and clinical purposes in Moroccan CRC patients.

微RNA-196a-1-3p靶向Ras响应元件结合蛋白调控胆管癌细胞增殖的机制研究

目的探讨转化生长因子β(TGF-β)调控人胆管癌细胞系RBE细胞增殖的关键微RNA(miRNA)及其潜在的机制。方法该研究起止时间为2020年1月至2022年1月。磷酸盐缓冲液(PBS)处理为对照组,TGF-β处理为TGF-β组,TGF-β抗体处理为抗体组。检测三组RBE细胞的增殖水平。miRNA高通量测序检测三组RBE细胞的miRNA调控变化,并进行miRNA模拟物过表达筛选鉴定受TGF-β调控的影响RBE细胞增殖水平的关键miRNA。miRNA数据库(miRDB)在线分析miRNA的潜在底物,并通过小干扰RNA(siRNA)敲低筛选鉴定影响RBE细胞增殖水平的关键底物。结果相比于对照组,TGF-β组RBE细胞的增殖水平上升(1.62±0.07比2.35±0.09,P<0.05),抗体组RBE细胞的增殖水平下降(1.62±0.07比1.11±0.08,P<0.05)。过表达微RNA-196a-1-3p(miR-196a-1-3p)时,RBE细胞的增殖水平下降(P<0.05)。敲低Ras响应元件结合蛋白(RREB1)时,RBE细胞的增殖水平下降(P<0.05)。过表达miR-196a-1-3p后,RBE细胞中RREB1的信使RNA(mRNA)和蛋白水平下降(P<0.05)。敲低miR-196a-1-3p后,RBE细胞中RREB1与SMAD家族蛋白3(SMAD3)的相互作用增加。敲低SMAD3后,RBE细胞的增殖水平下降(P<0.05)。与仅敲低SMAD3相比,敲低SMAD3的同时过表达RREB1的RBE细胞的增殖水平无显著变化,并且同时敲低SMAD3和miR-196a-1-3p的RBE细胞的增殖水平无显著变化。结论TGF-β能够通过miR-196a-1-3p/RREB1/SMAD3轴促进RBE细胞增殖;miR-196a-1-3p和RREB1可作为潜在的治疗胆管癌的靶标,为针对该靶标的新药研发奠定了基础。

低位直肠癌病人肛全直肠系膜切除术后中期排便功能障碍发生风险Nomogram模型构建

目的:分析影响低位直肠癌病人行肛全直肠系膜切除术(transanal total mesorectal excision,TaTME)后中期排便功能障碍发生的危险因素,并建立Nomogram模型。方法:选择2016年1月至2020年1月172例低位直肠癌并接受腹腔镜辅助TaTME手术病人作为建模组,选择2020年2月至2021年2月间接受相同手术病人32例作为验证组;建模组病人根据术后6个月随访时是否发生低位前切除综合征(low anterior resection syndrome,LARS)分为LARS组和非LARS组,比较2组病人病历资料,采用单因素和多因素logistic回归模型对影响LARS发生的独立危险因素进行分析,并采用R软件建立预测低位直肠癌病人TaTME术后LARS发生的列线图模型,并进行验证。结果:病人的LARS评分为(14.78±4.54)分,其中LARS病人84例(48.84%),非LARS病人LARS 88例(51.16%)。单因素、多因素logistic回归分析显示术前放疗、肛门括约肌损伤、吻合口距离肛缘距离、肿瘤直径、坐骨棘间径长度均是影响LARS的独立危险因素(P<0.05~P<0.01)。列线图模型预测建模组、验证组的C-index分别为0.836和0.827。ROC曲线显示,列线图模型预测建模组、验证组发生LARS的AUC分别为0.829、0.808。结论:术前放疗、肛门括约肌损伤、吻合口距离肛缘距离、肿瘤直径、坐骨棘间径长度是影响是否发生LARS的独立危险因素,以上述指标建立的列线图模型具有良好预测效能。

Study on the causes of local recurence of rectal cancer after curative resection:analysis of 213 cases

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Evidence-based medical oncology and interventional radiology paradigms for liver-dominant colorectal cancer metastases

Colorectal cancer metastasizes predictably, with liver predominance in most cases. Because liver involvement has been shown to be a major determinant of survival in this population, liver-directed therapies are increasingly considered even in cases where there is(limited) extrahepatic disease. Unfortunately, these patients carry a known risk of recurrence in the liver regardless of initial therapy choice. Therefore, there is a demand for minimally invasive, non-surgical, personalized cancer treatments to preserve quality of life in the induction, consolidation, and maintenance phases of cancer therapy. This report aims to review evidence-based conceptual, pharmacological, and technological paradigm shifts in parenteral and percutaneous treatment strategies as well as forthcoming evidence regarding next-generation systemic, locoregional, and local treatment approaches for this patient population.

Critical analysis of the literature investigating urogenital function preservation following robotic rectal cancer surgery

AIM To analyses the current literature regarding the urogenital functional outcomes of patients receiving robotic rectal cancer surgery. METHODS A comprehensive literature search of electronic databases was performed in October 2015. The following search terms were applied: "rectal cancer" or "colorectal cancer" and robot* or "da Vinci" and sexual or urolog* or urinary or erect* or ejaculat* or impot* or incontinence. All original studies examining the urological and/or sexual outcomes of male and/or female patients receiving robotic rectal cancer surgery were included. Reference lists of all retrieved articles were manually searched for further relevant articles. Abstracts were independently searched by two authors. RESULTS Fifteen original studies fulfilled the inclusion criteria. A total of 1338 patients were included; 818 received robotic, 498 laparoscopic and 22 open rectal cancer surgery. Only 726(54%) patients had their urogenital function assessed via means of validated functional questionnaires. From the included studies, three found that robotic rectal cancer surgery leads to quicker recovery of male urological function and five of male sexual function as compared to laparoscopic surgery. It is unclear whether robotic surgery offers favourable urogenital outcomes in the long run for males. In female patients only two studies assessed urological and threesexual function independently to that of males. In these studies there was no difference identified between patients receiving robotic and laparoscopic rectal cancer surgery. However, in females the presented evidence was very limited making it impossible to draw any substantial conclusions. CONCLUSION There seems to be a trend towards earlier recovery of male urogenital function following robotic surgery. To evaluate this further, larger well designed studies are required.

Intraoperative intraperitoneal chemotherapy increases the incidence of anastomotic leakage after anterior resection of rectal tumors

BACKGROUND Intraoperative intraperitoneal chemotherapy is an emerging treatment modality for locally advanced rectal neoplasms. However, its impacts on postoperative complications remain unknown. Anastomotic leakage (AL) is one of the most common and serious complications associated with the anterior resection of rectal tumors. Therefore, we designed this study to determine the effects of intraoperative intraperitoneal chemotherapy on AL. AIM To investigate whether intraoperative intraperitoneal chemotherapy increases the incidence of AL after the anterior resection of rectal neoplasms. METHODS This retrospective cohort study collected information from 477 consecutive patients who underwent an anterior resection of rectal carcinoma using the double stapling technique at our institution from September 2016 to September 2017. Based on the administration of intraoperative intraperitoneal chemotherapy or not, the patients were divided into a chemotherapy group (171 cases with intraperitoneal implantation of chemotherapy agents during the operation) or a control group (306 cases without intraoperative intraperitoneal chemotherapy). Clinicopathologic features, intraoperative treatment, and postoperative complications were recorded and analyzed to determine the effects of intraoperative intraperitoneal chemotherapy on the incidence of AL. The clinical outcomes of the two groups were also compared through survival analysis. RESULTS The univariate analysis showed a significantly higher incidence of AL in the patients who received intraoperative intraperitoneal chemotherapy, with 13 (7.6%) cases in the chemotherapy group and 5 (1.6%) cases in the control group (P = 0.001). As for the severity of AL, the AL patients who underwent intraoperative intraperitoneal chemotherapy tended to be more severe cases, and 12 (92.3%) out of 13 AL patients in the chemotherapy group and 2 (40.0%) out of 5 AL patients in the control group required a secondary operation (P = 0.044). A multivariate analysis was subsequently performed to adjust for the confounding factors and also showed that intraoperative intraperitoneal chemotherapy increased the incidence of AL (odds ratio = 5.386;95%CI: 1.808-16.042;P = 0.002). However, the survival analysis demonstrated that intraoperative intraperitoneal chemotherapy could also improve the disease-free survival rates for patients with locally advanced rectal cancer. CONCLUSION Intraoperative intraperitoneal chemotherapy can improve the prognosis of patients with locally advanced rectal carcinoma, but it also increases the risk of AL following the anterior resection of rectal neoplasms.

Down-staging depth score to predict outcomes in locally advanced rectal cancer achieving ypl stage after neoadjuvant chemo-radiotherapy versus de novo stage pl cohort:A propensity score-matched analysis

Objective：Prognosis of patients with locally advanced rectal cancer（LARC）but achieving yp T1–2N0 stage after neoadjuvant concurrent chemo-radiotherapy（CRT）has been shown to be favorable.This study aims to determine whether the long-term outcome of yp T1–2N0 cases can be comparable to that of p T1–2N0 cohort that received definitive surgery for early disease.Method：From January 2008 to December 2013,449 consecutive patients with rectal cancer were treated and their outcome maintained in a database.Patients with LARC underwent total mesorectal excision（TME）surgery at4–8 weeks after completion of CRT,and those achieving stage yp I were identified as a group.As a comparison,stage p I group pertains to patients whose initially limited disease was not upstaged after TME surgery alone.After propensity score matching（PSM）,comparisons of local regional control（LC）,distant metastasis-free survival（DMFS）,disease-free survival（DFS）and overall survival（OS）were performed using Kaplan-Meier analysis and log-rank test between yp I and p I groups.Down-staging depth score（DDS）,a novel method of evaluating CRT response,was used for subset analysis.Results：Of the 449 patients,168 matched cases were generated for analysis.Five-year LC,DMFS,DFS and OS for stage p I vs.yp I groups were 96.7%vs.96.4%（P=0.796）,92.7%vs.73.6%（P=0.025）,91.2%vs.73.6%（P=0.080）and 93.1%vs.72.3%（P=0.040）,respectively.In the DDS-favorable subset of the yp I group,LC,DMFS,DFS and OS resulted in no significant differences in comparison with the p I group（P=0.384,0.368,0.277 and0.458,respectively）.Conclusions：LC was comparable in both groups;however,distant metastasis developed more frequently in down-staged LARC than de novo early stage cases,reflecting the need to improve the efficacy of systemic treatment despite excellent pathologic response.DDS can be an indicator to identify a subset of the yp I group whose longterm oncologic outcomes are as good as those of stage p I cohort.

Low ligation has a lower anastomotic leakage rate after rectal cancer surgery

BACKGROUND For laparoscopic rectal cancer surgery,the inferior mesenteric artery(IMA)can be ligated at its origin from the aorta[high ligation(HL)]or distally to the origin of the left colic artery[low ligation(LL)].Whether different ligation levels are related to different postoperative complications,operation time,and lymph node yield remains controversial.Therefore,we designed this study to determine the effects of different ligation levels in rectal cancer surgery.AIM To investigate the operative results following HL and LL of the IMA in rectal cancer patients.METHODS From January 2017 to July 2019,this retrospective cohort study collected information from 462 consecutive rectal cancer patients.According to the ligation level,235 patients were assigned to the HL group while 227 patients were assigned to the LL group.Data regarding the clinical characteristics,surgical characteristics and complications,pathological outcomes and postoperative recovery were obtained and compared between the two groups.A multivariate logistic regression analysis was performed to evaluate the possible risk factors for anastomotic leakage(AL).RESULTS Compared to the HL group,the LL group had a significantly lower AL rate,with 6(2.8%)cases in the LL group and 24(11.0%)cases in the HL group(P=0.001).The HL group also had a higher diverting stoma rate(16.5%vs 7.5%,P=0.003).A multivariate logistic regression analysis was subsequently performed to adjust for the confounding factors and confirmed that HL(OR=3.599;95%CI:1.374-9.425;P=0.009),tumor located below the peritoneal reflection(OR=2.751;95%CI:0.772-3.985;P=0.031)and age(≥65 years)(OR=2.494;95%CI:1.080-5.760;P=0.032)were risk factors for AL.There were no differences in terms of patient demographics,pathological outcomes,lymph nodes harvested,blood loss,hospital stay and urinary function(P>0.05).CONCLUSION In rectal cancer surgery,LL should be the preferred method,as it has a lower AL and diverting stoma rate.

Selective lateral lymph node dissection after neoadjuvant chemoradiotherapy in rectal cancer

BACKGROUND Lateral lymph node metastasis is one of the leading causes of local recurrence in patients with advanced mid or low rectal cancer.Neoadjuvant chemoradiotherapy(NCRT)can effectively reduce the postoperative recurrence rate;thus,NCRT with total mesorectal excision(TME)is the most widely accepted standard of care for rectal cancer.The addition of lateral lymph node dissection(LLND)after NCRT remains a controversial topic.AIM To investigate the surgical outcomes of TME plus LLND,and the possible risk factors for lateral lymph node metastasis after NCRT.METHODS This retrospective study reviewed 89 consecutive patients with clinical stage II-III mid or low rectal cancer who underwent TME and LLND from June 2016 to October 2018.In the NCRT group,TME plus LLND was performed in patients with short axis(SA)of the lateral lymph node greater than 5 mm.In the non-NCRT group,TME plus LLND was performed in patients with SA of the lateral lymph node greater than 10 mm.Data regarding patient demographics,clinical workup,surgical procedure,complications,and outcomes were collected.Multivariate logistic regression analysis was performed to evaluate the possible risk factors for lateral lymph node metastasis in NCRT patients.RESULTS LLN metastasis was pathologically confirmed in 35 patients(39.3%):26(41.3%)in the NCRT group and 9(34.6%)in the non-NCRT group.The most common site of metastasis was around the obturator nerve(21/35)followed by the internal iliac artery region(12/35).In the NCRT patients,46%of patients with SA of LLN greater than 7 mm were positive.The postoperative 30-d mortality rate was 0%.Two(2.2%)patients suffered from lateral local recurrence in the 2-year follow up.Multivariate analysis showed that cT4 stage(odds ratio[OR]=5.124,95%confidence interval[CI]:1.419-18.508;P=0.013),poor differentiation type(OR=4.014,95%CI:1.038-15.520;P=0.044),and SA≥7 mm(OR=7.539,95%CI:1.487-38.214;P=0.015)were statistically significant risk factors associated with LLN metastasis.CONCLUSION NCRT is not sufficient as a stand-alone therapy to eradicate LLN metastasis in lower rectal cancer patients and surgeons should consider performing selective LLND in patients with greater LLN SA diameter,poorer histological differentiation,or advanced T stage.Selective LLND for NCRT patients can have a favorable oncological outcome.

Using Materialise’s interactive medical image control system to reconstruct a model of a patient with rectal cancer and situs inversus totalis: A case report

BACKGROUND Situs inversus totalis(SIT)is a rare congenital anomaly that refers to a completely reversed location of abdominal and thoracic organs.An extremely small number of patients with this condition,especially those with rectal neoplasms,have been reported.Surgery in these patients is technically challenging.Therefore,we reconstructed a three-dimensional(3D)digital model with the Materialise’s interactive medical image control system(Mimics)as a guide for laparoscopic resection.CASE SUMMARY We report the case of a 68-year-old woman with rectal neoplasms and SIT diagnosed by electronic colonoscopy biopsy and enhanced computed tomography(CT),which showed that there was a soft tissue mass protruding into the lumen in the lower rectal segment,a lesion that involved the serosal layer,multiple enlarged peripheral lymph nodes,and visceral situs abnormalities.Based on the CT images,we reconstructed a 3D model with Mimics to assist with our surgical planning.Then,we performed laparoscopyassisted radical resection of the rectal neoplasms and total excision of the lesion.Adjuvant chemotherapy with the XELOX regimen(oxaliplatin 150 mg,D1+Xeloda 1.0 g,Bid,D1-14)was initiated 1 mo after the operation.The patient recovered well after surgery,and her physical condition remained stable.CONCLUSION Preoperative 3D reconstruction of the imaging results could help reduce the unknown risks during surgery caused by anatomical abnormalities and improvethe perioperative safety for patients.

Expression of p53 and p21 Protein in Transitional Mucosa Adjacent to Rectal Carcinoma and Its Clinical Implication

To study the biopathological characteristics of the transitional mucosa adjacent to rectal carcinoma, 34 cases were subjected to mucin histochemical and immunohistochemical study to observe the expression of p53 and p21 protein in distal mucosa adjacent to rectal carcinoma and its relationship to the mucin change. The expression of p53 protein was found in 29. 4 % (10/34) of distal transitional mucosa in the cytoplasm of goblet cells, and its positive staining was within 4 cm from carcinoma margin. A11 p53 positive mucosa was transitional mucosa. Overexpression of p21 protein was found in 26.5 % (9/34) of distal transitional mucosa in cytoplasm of crypt cells, and its positive staining was within 2 cm from carcinoma margin. There was no relationship between the expression of p53 and p21 protein in carcinoma and that in transitional mucosa ( P >0.05). These findings indicated that there was aberrant alteration of p53 and p21 genes in transitional mucosa adjacent to colorectal carcinoma, which provided further evidence that transitional mucosa was an unstable pre cancerous change. The aberrant mucin change and genetic alteration in distal mucosa of rectal cancer is within 4 cm.

K-Ras、BRAF、PIK3CA基因突变与直肠癌新辅助放化疗疗效及预后的关系

目的:探讨K-Ras、BRAF、PIK3CA基因突变与直肠癌新辅助放化疗(nCRT)疗效及预后的关系。方法:选取2015年03月至2020年03月于医院接受nCRT并行根治手术的直肠癌患者182例作为研究对象。所有患者术前接受卡培他滨化疗,同时采用长程分割疗法进行放疗,共治疗5周,nCRT结束后5~12周,根据肿瘤位置及nCRT情况行手术治疗,出院后进行为期1年的随访。以肿瘤退缩分级(TRG)评价直肠癌nCRT疗效,TRG 1-3级纳入nCRT有效组,TRG 4-5级纳入nCRT无效组。nCRT前经肠镜取肿瘤组织,检测K-Ras、BRAF、PIK3CA基因突变状态,分析K-Ras、BRAF、PIK3CA基因突变与直肠癌nCRT疗效及预后的关系。结果:在182例直肠癌患者中,K-Ras、BRAF、PIK3CA基因突变率分别为34.07%、6.59%、13.19%,nCRT治疗有效率为60.44%。nCRT有效组K-Ras、BRAF及PIK3CA基因突变率显著低于nCRT无效组(P<0.05)。K-Ras、BRAF、PIK3CA基因突变状态预测直肠癌nCRT疗效的敏感度分别为68.45%、65.38%、57.76%,特异度分别为72.39%、69.23%、63.12%,AUC分别为0.626、0.573、0.532。Logistic回归分析结果显示K-Ras、BRAF、PIK3CA基因突变与直肠癌nCRT疗效显著相关(P<0.05)。K-Ras、BRAF、PIK3CA基因突变患者平均生存时间均分别短于K-Ras、BRAF、PIK3CA无突变者,差异有统计学意义(P<0.05)。多变量COX回归分析结果显示K-Ras、BRAF及PIK3CA基因突变患者死亡风险分别是K-Ras、BRAF、PIK3CA无突变者的1.639倍、1.811倍、1.432倍(P<0.05)。结论:K-Ras、BRAF、PIK3CA基因突变与直肠癌患者nCRT疗效和预后相关,可作为nCRT疗效和预后的预测指标。