摘要：Cirrhosis with complications of liver decompensation and hepatocellular carcinoma(HCC)constitute a leading cause of morbidity and mortality worldwide.Portal hypertension is central to the progression of liver disease and decompensation.The most recent Baveno VII guidance included revision of the nomenclature for chronic liver disease,termed compensated advanced chronic liver disease,and leveraged the use of liver stiffness measurement to categorize the degree of portal hypertension.Additionally,non-selective beta blockers,especially carvedilol,can improve portal hypertension and may even have a survival benefit.Procedural techniques with interventional radiology have become more advanced in the management of refractory ascites and variceal bleed-ing,leading to improved prognosis in patients with decompensated liver disease.While lactulose and rifaximin are the preferred treatments for hepatic encephalopathy,many alternative treatment options may be used in refractory cases and even procedural interventions such as shunt embolization may be of benefit.The approval of terlipressin for the treatment of hepatorenal syndrome(HRS)in the USA has improved the way in which HRS is managed and will be discussed in detail.Malnutrition,frailty,and sarcopenia lead to poorer outcomes in patients with decompensated liver disease and should be addressed in this patient population.Palliative care interventions can lead to improved quality of life and clinical outcomes.Lastly,the investigation of systemic therapies,in partic-ular immunotherapy,has revolutionized the management of HCC.These topics will be discussed in detail in this review.

摘要：Background:The efficacy of adjuvant chemotherapy(AC)on survival outcomes of patients with stage Ⅰ gastric cancer(GC)after curative resection remains controversial.We aimed to determine whether these patients would benefit from AC. Methods:This retrospective study included patients with pathologically confirmed stage Ⅰ GC who underwent curative resection between November 2010 and December 2020.Patients were divided into AC and non-AC groups,then a 1∶1 propensity score matching(PSM)analysis was performed to minimize the selection bias.Potential risk factors including age,pN stage,pT stage,lymphovascular invasion,perineural invasion,tumor size,histological type,and carcinoembryonic antigen level were used as matching covariates.The recurrence-free survival(RFS)and disease-specific survival(DSS)were compared between groups using the Kaplan-Meier method. Results:A total of 902 consecutive patients were enrolled and 174(19.3％)patients were treated with AC.PSM created 123 pairs of patients.Before PSM,patients receiving AC had lower 10-year RFS rates(90％ vs 94.6％,P=0.035)than those who did not receive AC;the two groups had similar 10-year DSS rates(93.8％ vs 95.0％,P=0.240).After PSM,there were no statistical differences in the 10-year RFS(90.9％ vs 93.0％,P=0.507)or DSS rates(93.5％ vs 93.6％,P=0.811)between the two groups.Similar results were found in the stage ⅠA and ⅠB subgroups.Moreover,these findings were not affected by AC cycles. Conclusions:The addition of AC could not provide survival benefits for patients with stage Ⅰ GC after surgery and follow-up is thus recommended.However,large-scale randomized clinical trials are required.

摘要：Introduction Small intestinal diseases cannot be accurately located by using imaging,so small intestinal endoscopic ultrasound(SIEUS)is needed to evaluate submucosal changes,invasion degree,and extent of submucosal lesions.As double balloon enteroscopy(DBE)is extensively employed,small intestinal diseases are fre-quently detected,and enteroscopy-guided treatments(e.g.enteroscopy-guided small intestinal polypectomy)are increas-ingly available[1].Although enteroscopy enables direct observa-tion of small intestinal lesions,it does not enable observation of the deep-seated layers of the intestinal wall.Based on entero-scopy combined with SIEUS,the histological characteristics of various layers of the intestinal lumen and endoscopic ultrasound images of peripheral and neighboring organs can be obtained to observe the layers from which small intestinal lesions originate.

摘要：The landscape of liver disease management continues to evolve,with notable advancements in non-invasive diagnostics,understand-ing of perioperative risk,new therapies for cirrhotic complications,metabolic dysfunction-associated steatotic liver disease(MASLD),and alcohol-associated liver disease(ALD),as well as screening for hepatocellular carcinoma(HCC)and the management of special populations such as mothers with hepatitis B.In this Special Issue of Gastroenterology Report,we have compiled a collection of review articles that discuss practical approaches to managing common liver diseases,including HCC screening,non-invasive assessment of fibro-sis,multifaceted approaches to perioperative care and cirrhotic com-plications,and postpartum hepatitis flare in mothers with hepatitis B.Additionally,this issue provides concise reviews on the immune mechanisms in MASLD,highlighting critical findings and paving the way for future research directions.

摘要：Achieving a sustained virologic response(SVR)through direct-acting antivirals for hepatitis C virus(HCV)infection significantly reduces the long-term risk of hepatocellular carcinoma(HCC),particularly in patients with advanced fibrosis(F3)or cirrhosis(F4).However,despite this improvement,the risks associated with HCC and the optimal surveillance strategies for patients who have achieved SVR remain topics of debate.This controversy is compounded by challenges in reliably staging liver fibrosis non-invasively,especially at advanced fibrosis(F3),and the unclear cost-effectiveness,modality,frequency,and duration of HCC surveillance in indi-viduals with SVR but without cirrhosis.These factors contribute to significant variations in surveillance guidelines recommended by different professional societies.Therefore,there is a pressing need for an optimal surveillance strategy that is both simplified and cost-effective to facilitate wider adoption by clinicians.This review article evaluates the existing data,addresses ongoing controver-sies,and aims to provide new perspectives on HCC surveillance strategies for patients who have achieved SVR from HCV.

摘要：Background:Accumulating researchers have recognized mitophagy as a key player in tumors,but few studies have investigated its role in the tumor microenvironment(TME).Advances in the technology of single-cell RNA sequencing(scRNA-seq)have allowed unveiling the concealed features of the TME at cellular resolution.This study aimed to elucidate the role of mitophagy within the TME of colorectal cancer(CRC)and to establish a mitophagy-mediated risk model. Methods:We assessed mitophagy-related pathway activities at both single-cell and tissue levels.Subsequently,an unsupervised clustering algorithm was employed to identify mitophagy-mediated subtypes.Furthermore,we developed a mitophagy-mediated risk signature(MMRS)using least absolute shrinkage and selection operator(LASSO)Cox analysis and constructed a MMRS model incorporating the risk score and clinical variables.Subsequently,we used quantitative reverse transcription polymerase chain reac-tion analysis to verify the expression of the screened genes. Results:We retrieved and annotated a total of 14,719 cells from eight samples in the scRNA-seq GSE132465 data set.The activities of mitophagy-related pathways were uniformly upregulated in cancer cells.Integrating with bulk RNA-seq data,we identified two mitophagy-mediated clusters(C1 and C2)with distinct characteristics and prognoses.C2 was identified as a mitophagy-high cluster.Then,we developed a five-gene MMRS via LASSO Cox analysis in The Cancer Genome Atlas(TCGA)cohort.We utilized the GSE39582 cohort to validate the efficacy of our model.The expression of CX3CL1 and INHBB was upregulated in CRC tissues. Conclusions:The present study identified two mitophagy-mediated CRC subtypes with distinct features.Our MMRS may provide potential therapeutic strategies for CRC.The findings of our work offer novel insights into the involvement of mitophagy in CRC.

摘要：Inflammatory bowel disease(IBD)research often relies on animal models to study the etiology,pathophysiology,and management of IBD.Among these models,rats and mice are frequently employed due to their practicality and genetic manipulability.However,for studies aiming to closely mimic human pathology,non-human primates such as monkeys and dogs offer valuable physiological parallels.Guinea pigs,while less commonly used,present unique advantages for investigating the intricate interplay between neurological and immunological factors in IBD.Additionally,New Zealand rabbits excel in endoscopic biopsy techniques,providing insights into mucosal inflammation and healing processes.Pigs,with their physiological similarities to humans,serve as ideal models for exploring the complex relationships between nutrition,metabolism,and immunity in IBD.Beyond mammals,non-mammalian organisms including zebrafish,Drosophila melanogaster,and nematodes offer specialized insights into specific aspects of IBD pathology,highlighting the diverse array of model systems available for advancing our understanding of this multifaceted disease.In this review,we conduct a thorough analysis of various animal models employed in IBD research,detailing their applications and essential experimental parameters.These include clinical observation,Disease Activity Index score,pathological assessment,intestinal barrier integrity,fibrosis,inflammatory markers,intestinal microbiome,and other critical parameters that are crucial for evaluating modeling success and drug efficacy in experimental mammalian studies.Overall,this review will serve as a valuable resource for researchers in the field of IBD,offering insights into the diverse array of animal models available and their respective applications in studying IBD.

摘要：Introduction Lynch syndrome(LS)is an autosomal dominant condition caused by pathogenic variants in mismatch repair(MMR)genes.LS is as-sociated with an 80％lifetime risk for colorectal cancer(CRC);it is also characterized by extracolonic tumors,including endome-trial,stomach,or ovarian cancer[1,2].

摘要：Background:Non-alcoholic fatty liver disease(NAFLD)is a major contributor to liver diseases globally,yet there are limited studies investigating the impact of diet and lifestyle factors on its development.This study aimed to examine the association between the prevalence of NAFLD and predicted pro-inflammatory high-sensitivity C-reactive protein(hs-CRP)score. Methods:We included 1,076 Korean adults who underwent a medical examination at the Seoul National University Hospital Gangnam Healthcare Center in Korea between May and December 2011 and updated in 2021.The predicted pro-inflammatory hs-CRP score was derived from pro-inflammatory demographic,lifestyle,dietary,and anthropometric factors,and NAFLD was diagnosed using liver ultrasound.Multivariable-adjusted odds ratios(ORs)and 95％confidence intervals(CIs)of NAFLD odds accord-ing to predicted pro-inflammatory hs-CRP score were estimated using logistic regression at a two-sided P＜0.05. Results:Among the 1,076 participants,320 had NAFLD.The multivariable-adjusted ORs and 95％CIs for NAFLD by tertiles of predicted pro-inflammatory hs-CRP score were 1.00,3.30(2.06,5.30),18.25(10.47,31.81;P＜0.0001)in men and women combined,1.00,1.77(1.10,2.84),and 3.26(2.02,5.28;P＜0.0001)among men only,and 1.00,3.03(1.39,6.62),and 16.71(7.05,39.63;P＜0.0001)among women only. Conclusions:Predicted pro-inflammatory hs-CRP score was associated with higher odds of NAFLD.Adopting dietary and lifestyle changes related to lower inflammation might be a valuable strategy for preventing NAFLD.

摘要：Non-alcoholic fatty liver disease,recently renamed metabolic dysfunction-associated steatotic liver disease(MASLD),is a complex multifactorial disease that progresses from steatohepatitis(MASH)to liver cirrhosis and liver cancer.Recent research has revealed that crosstalk between innate immune cells and hepatic parenchymal and non-parenchymal cells is involved in the pathogenesis of liver disease in MASLD/MASH.Of particular importance,novel inflammatory mechanisms,including macrophage diversity,neutro-phil NETosis,B-cell biology,auto-reactive T cells,unconventional T cells,and dendritic cell-T cell interactions,are considered key drivers for disease progression.These mechanisms and factors are potential targets for the therapeutic intervention of MASLD/MASH.In this review,we focus on recent discoveries related to liver inflammation and discuss the role of innate immune cell subsets in MASLD/MASH.

摘要：Background:Exclusive enteral nutrition(EEN)therapy effectively induces remission in pediatric Crohn's disease(CD).However,this may depend on the type of enteral formula used.Moreover,data on the efficacy of amino acid-based EEN are limited.Thus,we aimed to prospectively evaluate the efficacy of amino acid-based formulas for EEN in pediatric patients with active CD. Methods:Patients with active CD aged between 6 and 17 years were recruited into this prospective study from four hospitals in China between March 2019 and December 2021.Patients received EEN for 8 weeks.Inflammatory and nutrition-associated indices were evaluated at 0,4,and 8 weeks after treatment.Paired t-tests and Wilcoxon signed-rank tests were used to compare continuous and categorical variables before and after intervention,respectively. Results:Twenty-four patients were included in the analysis.After an 8-week intervention period,the CD activity index significantly decreased(26.3±12.2 vs 7.1±8.3,P<0.001).Most patients(66.7%)achieved complete clinical remission.Among the 22 patients who had ulcers and erosions diagnosed endoscopically at baseline,10(45.5%)achieved complete mucosal healing.The degree of thicken-ing of the intestinal wall was significantly reduced after EEN intervention,with a transmural healing rate of 42.9%.Furthermore,the serum inflammatory markers decreased and there was a significant improvement in the nutrition-related indices(P<0.05).There were no severe adverse effects. Conclusions:Amino acid-based EEN is effective and safe for treating pediatric-onset CD.Studies with larger sample sizes and mech-anistic and follow-up studies are required to further validate these findings.

摘要：Background:MLH1 promoter methylation analysis is recommended in screening for Lynch syndrome(LS)in patients with MLH1-deficient colorectal cancer(CRC).The study aims to identify specific methylation regions in the MLH1 promoter and to evaluate the clinicopathologic characteristics of and prognosis for patients with MLH1 methylation. Methods:A total of 580 CRC cases were included.The DNA mismatch repair(MMR)protein expression was assessed by using immu-nohistochemistry(IHC).The methylation status of the Regions A,B,C,D,and E in the MLH1 promoter was tested by using bisulfite sequencing PCR.The specificities of the five regions were calculated.Associations between MLH1 methylation and clinicopathologic characteristics were evaluated.Kaplan-Meier analyses for overall survival(OS)were carried out. Results:In 580 CRC cases,the specificities of the methylation test in Regions D and E were both 97.8%.In the MLH1-deficient CRCs,the frequencies of MLH1 methylation and BRAFV600E mutation were 52.6%and 14.6%,respectively;BRAFV600E mutation occurred in 27.7%of patients with MLH1-methylated CRC.In the MMR-deficient patients,compared with MLH1 unmethylation,MLH1 methyla-tion was more common in patients who were aged≥50 years,female,had no family history of LS-related tumors,and had tumors located at the right colon.In the MMR-deficient patients,the MLH1-methylated cases had lower OS rates than the unmethylated cases with a family history of LS-related tumors(P=0.047). Conclusions:Regions D and E in the MLH1 promoter are recommended for determining the MLH1 methylation status in screening for LS in MLH1-deficient CRC.In MMR-deficient patients,the MLH1-methylated cases had a worse OS than the unmethylated cases with a family history of LS-related cancer.

摘要：Background:Binge drinking(BD)has been associated with elevated liver enzymes,but the joint association of BD and adiposity with liver enzymes is understudied.We aimed to examine the combined association of BD and obesity with elevated liver enzymes. Methods:Data were obtained from 285,600 patients in the Korean National Health check-up program during 2009-2015.Level I BD(BD I)was defined as alcohol consumption of>60 g(men)or>40 g(women)on one occasion in the previous year.High-intensity BD(HIBD)corresponded to at least two times the BD I levels.General and abdominal obesity were defined by body mass index and waist circumference.Logistic regression was used to examine the independent and joint associations of BD and obesity with elevated ala-nine aminotransferase(ALT),aspartate aminotransferase(AST),and gamma-glutamyl transferase(GGT)levels.Relative excess risk(RERI),attributable proportion(AP),and synergy index(SI)were calculated to estimate the additive interaction effects. Results:The mean age was 42.1±0.03 years and 50.2%were women.Elevated ALT[odds ratio(OR)1.09,95%confidence interval(CI)1.02-1.16],AST(OR 1.16,95%CI 1.11-1.23),and GGT(OR 1.84,95%CI 1.05-1.94)were associated with HIBD.Higher odds of elevated ALT(OR 3.57,95%CI 3.43-3.71),AST(OR 3.47,95%CI 3.37-3.58),and GGT(OR 2.10,95%CI 1.98-2.12)were observed in individuals with general obesity.A similar trend was observed for abdominal obesity.The RERI,AP,and SI for the interaction effect of BD and general obesity were 23%,7%,and 13%for elevated AST levels,and 67%,24%,and 58%for elevated GGT levels,respectively.Similar effects were observed for the interaction between BD and abdominal obesity. Conclusions:Obesity aggravated the odds of elevated liver AST and GGT levels in HIBD.

摘要：Introduction Histoplasmosis is a mycotic infection caused by Histoplasma cap-sulatum.The usual clinical presentation is pulmonary disease.Disseminated disease can occur and involve multiple organs[1].Gastrointestinal(GI)involvement can be seen in 70％of autopsy cases,but only 3％-12％are symptomatic[1].Moreover,isolated GI histoplasmosis without accompanying pulmonary symptoms is exceedingly rare.Recognizing this rare entity can be difficult,especially in patients with pre-existing GI disorders such as in-flammatory bowel disease(IBD).

摘要：Background:The effect of neoadjuvant immunotherapy on minimally invasive gastrectomy(MIG)for locally advanced gastric cancer(LAGC)remains controversial.This study aimed to compare short-term outcomes between MIG after neoadjuvant chemo-immunotherapy(NICT-MIG)and MIG after neoadjuvant chemotherapy alone(NCT-MIG),and determine risk factors for post-operative complications(POCs). Methods:This retrospective study included clinicopathologic data from 193 patients who underwent NCT-MIG or NICT-MIG between January 2020 and February 2023 in the Department of General Surgery,Chinese People’s Liberation Army General Hospital First Medical Center(Beijing,China).Propensity score-matched analysis at a ratio of 1:2 was performed to reduce bias from confounding patient-related variables and short-term outcomes were compared between the two groups. Results:The baseline characteristics were comparable between 49 patients in the NICT-MIG group and 86 patients in the NCT-MIG group after propensity score matching.Objective and pathologic complete response rates were significantly higher in the NICT-MIG group than in the NCT-MIG group(P<0.05).The overall incidence of treat-related adverse events,intraoperative bleeding,operation time,number of retrieved lymph nodes,time to the first flatus,post-operative duration of hospitalization,overall morbidity,and se-vere morbidity were comparable between the NCT-MIG and NICT-MIG groups(P>0.05).By multivariate logistic analysis,estimated blood loss of>200 mL(P¼0.010)and prognostic nutritional index(PNI)score of<45(P¼0.003)were independent risk factors for POCs after MIG following neoadjuvant therapy. Conclusions:Safety and feasibility of NICT were comparable to those of NCT in patients undergoing MIG for LAGC.Patients with an estimated blood loss of>200 mL or a PNI score of<45 should be carefully evaluated for increased POCs risk.

摘要：Postpartum elevation of alanine aminotransferase(ALT)in mothers with chronic hepatitis B(CHB)presents a significant clinical challenge.However,the existing literature demonstrates inconsistencies regarding its incidence and predictors in mothers infected with the hepatitis B virus(HBV).Recent advancements in antiviral prophylaxis against mother-to-child transmission of HBV and postpartum cessation of antiviral therapy further complicate this issue.Our literature review,spanning PubMed,and two Chinese-language databases(CNKI and Wanfang)from 1 January 2000 to 31 December 2023 aimed to consolidate and analyse available data on the frequency and severity of postpartum ALT flares,identify risk factors,and propose a management algorithm.Data from 23 eli-gible studies involving 8,077 pregnant women revealed an overall incidence of postpartum ALT elevation:25.7%for mild cases,4.4%for moderate cases,and 1.7%for severe cases.In the subgroup of mothers who were HBeAg-positive and on antiviral prophylaxis for preventing mother-to-child transmission,postpartum intermediate and severe ALT elevations were reported with pooled rates of 5.9%and 0.8%,respectively.Importantly,none resulted in mortality or necessitated liver transplantation.Identified risk factors for postpartum ALT flares in mothers with CHB included HBV DNA levels,ALT levels during pregnancy,postpartum cessation of antivi-ral treatment,and HBeAg status.By leveraging this evidence and recent data on predictors of intermediate or severe postpartum ALT flares,we propose a risk-stratified algorithm for managing postpartum ALT elevation and selecting therapy in mothers with CHB,tai-loring different approaches for treatment-naive vs treatment-experienced populations.These recommendations aim to provide guidance for clinical decision-making and enhance patient outcomes.

摘要：Background:Systemic chemotherapy for gastric cancer with peritoneal metastasis has limited clinical benefit;for those with intraopera-tive detection of occult peritoneal metastasis,cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy(HIPEC)is an alternative treatment.However,the feasibility and effects of this modality and criteria for selecting suitable groups remain unclear.This study aimed to explore the safety and efficacy of laparoscopic cytoreductive surgery(L-CRS)followed by HIPEC in gastric cancer with limited peritoneal metastasis,and this study also aimed to determine the optimized cut-off of the peritoneal cancer index. Methods:Between March 2017 and November 2019,patients diagnosed with gastric cancer peritoneal metastases by using laparoscopy and the Sugarbaker peritoneal cancer index of?12 were eligible for inclusion.All patients received L-CRS(including gastrectomy with D2 lymph node dissection)and resection of visible peritoneal metastasis,followed by post-operative HIPEC,and systemic chemotherapy.The primary end points were median progression-free survival and median survival time,and the secondary outcomes were morbidity and mortality within 30 days after surgery. Results:Thirty patients were eligible for analysis,of whom 19(63.3%)were female,and the overall mean age was 53.0 years.The post-operative morbidity was 20%and the severe complication rate was 10%.The median survival time was 27.0 months with a 2-year overall survival rate of 52.3%and median progression-free survival was 14.0 months with a 2-year progression-free survival of 30.4%. Conclusions:L-CRS followed by HIPEC can be safely performed for gastric cancer with limited peritoneal metastasis and potential survival benefits.

摘要：Background:Compared with conventional laparoscopic surgery,natural orifice specimen extraction surgery(NOSES)has many advantages.Laparoscopic right colectomy with transvaginal specimen extraction has been reported,but the safety and feasibility of transrectal specimen extraction in male patients with ascending colon cancer remain to be verified.This study aimed to preliminar-ily evaluate the feasibility and safety of laparoscopic right hemicolectomy with transrectal specimen extraction. Methods:The study was conducted at a single tertiary medical center in China.A total of 494 consecutive patients who underwent laparoscopic right colectomy between September 2018 and September 2020 were included.Transrectal specimen extraction was performed in 40 male patients(the NOSES group).Patients in the NOSES group were matched to the conventional laparoscopic group using propensity score matching at a 1∶2 ratio.Short-term and long-term outcomes between the two groups were compared and evaluated. Results:Forty patients in the NOSES group and 80 patients in the conventional laparoscopic group were matched for analysis.Baseline characteristics were balanced after propensity matching.The operative features,including operating time,intraoperative bleeding,and the number of harvested lymph nodes,were statistically comparable in both groups.In terms of post-operative recov-ery,patients in the NOSES group showed preferable outcomes,as evidenced by less post-operative pain and faster return to flatus,defecation,and discharge.The post-operative complications rate,according to the Clavien-Dindo classification system,was similar in both groups.No differences in overall survival or disease-free survival were observed between the two groups. Conclusions:Laparoscopic right colectomy with transrectal specimen extraction is oncologically safe.Compared with conventional laparoscopic right colectomy,it can reduce post-operative pain,accelerate post-operative recovery,shorten the hospital stay,and achieve better cosmetic effect.

摘要：Background:Insufficient post-operative future liver remnant(FLR)limits the feasibility of hepatectomy for patients.Staged hepatectomy is an effective surgical approach that can improve the resection rate of hepatocellular carcinoma(HCC).This study aimed to compare the safety and efficacy of laparoscopic microwave ablation and portal vein ligation for staged hepatectomy(LAPS)and classical associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)in the treatment of hepatitis B virus(HBV)-related HCC. Methods:Clinical data of patients with HBV-related HCC who underwent LAPS or ALPPS in our institute between January 2017 and May 2022 were retrospectively analysed. Results:A total of 18 patients with HBV-related HCC were retrospectively analysed and divided into the LAPS group(n=9)and ALPPS group(n=9).Eight patients in the LAPS group and eight patients in the ALPPS group proceeded to a similar resection rate(88.9％vs 88.9％,P=1.000).The patients undergoing LAPS had a lower total comprehensive complication index than those undergoing ALPPS but there was not a significant different between the two groups(8.66 vs 35.87,P=0.054).The hypertrophy rate of FLR induced by ALPPS tended to be more rapid than that induced by LAPS(24.29 vs 13.17 mL/d,P=0.095).The 2-year recurrence-free survival(RFS)was 0％for ALPPS and 35.7％for LAPS(P=0.009),whereas the 2-year overall survival for ALPPS and LAPS was 33.3％and 100.0％(P=0.052),respectively. Conclusions:LAPS tended to induce lower morbidity and FLR hypertrophy more slowly than ALPPS,with a comparable resection rate and better long-term RFS in HBV-related HCC patients.

摘要：Introduction Anal cancer is a rare cancer accounting for～2％of all gastroin-testinal tract malignancies[1].Among anal cancers,squamous cell cancer(SCC)is the most common and lymphoma is one of the least frequent.The gastrointestinal tract is the most common site for extranodal non-Hodgkin's lymphoma(NHL),and diffuse large B-cell lymphoma(DLBCL)is the most common histologic subtype.However,primary colorectal lymphoma accounts for only 0.3％of all large intestinal malignancies and～3％of all gas-trointestinal lymphomas[2].Anal canal SCC and lymphomas are treated differently;thus,accurate diagnosis is crucial.