Colonoscopy plays an important role in detecting colorectal neoplasms in patients with gastric neoplasms

BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,respectively.Nowadays,GC is reported to have a potential predictive value for CRC,especially for advanced CRC.AIM To evaluate the necessity of colonoscopy for gastric neoplasm(GN)patients.METHODS Four databases,including PubMed,EMBASE,the Cochrane Library,and Ovid,were used to perform the search strategy on May 2,2023.The prevalence of colorectal neoplasms(CRN)and baseline characteristics were compared between the neoplasm group and the control group.Continuous variables are expressed as the mean difference and standard deviation.Relationships of categorical variables in the two groups are expressed as odds ratios(OR)and 95%confidence intervals(95%CIs).Subgroup analysis according to different kinds of GNs was conducted for more in-depth analysis.The results of this study are represented by forest plots.Publication bias was evaluated by a funnel plot.All data analyses were performed by STATA SE 16.0 software.RESULTS A total of 3018 patients with GNs and 3905 healthy controls(age and sex matched)were enrolled for analysis.After comparing the prevalence of CRNs between the two groups,CRNs were detected significantly more frequently in GN patients than in controls(OR=1.69,95%CI=1.28 to 2.23,I^(2)=85.12%,P=0.00),especially in patients with GC(OR=1.80,95%CI=1.49 to 2.18,I^(2)=25.55%,P<0.1).Moreover,other risk factors including age(OR=1.08,95%CI=1.00 to 1.17,I^(2)=90.13%,P=0.00)and male sex(OR=2.31,95%CI=1.26 to 4.22,I^(2)=87.35%,P=0.00),were related to the prevalence of CRNs.For patients in the GN group,body mass index(BMI,OR=0.88,95%CI=0.80 to 0.98,I^(2)=0.00%,P=0.92)and smoking(OR=1.03,95%CI=1.01 to 1.05,I^(2)=0.00%,P=0.57)were protective and risk factors for CRNs,respectively.CONCLUSION Patients are recommended to undergo colonoscopy when diagnosed with GNs,especially GC patients with a low BMI and a history of smoking.

Different lymph node staging systems for predicting the prognosis of colorectal neuroendocrine neoplasms

BACKGROUND Colorectal neuroendocrine neoplasms(NENs)are a rare malignancy that primarily arises from the diffuse distribution of neuroendocrine cells in the colon and rectum.Previous studies have pointed out that the status of lymph node may be used to predict the prognosis.AIM To investigate the predictive values of lymph node ratio(LNR),positive lymph node(PLN),and log odds of PLNs(LODDS)staging systems on the prognosis of colorectal NENs treated surgically,and compare their predictive values.METHODS This cohort study included 895 patients with colorectal NENs treated surgically from the Surveillance,Epidemiology,and End Results database.The endpoint was mortality of patients with colorectal NENs treated surgically.X-tile software was utilized to identify most suitable thresholds for categorizing the LNR,PLN,and LODDS.Participants were selected in a random manner to form training and testing sets.The prognosis of surgically treating colorectal NENs was examined using multivariate cox analysis to assess the associations of LNR,PLN,and LODDS with the prognosis of colorectal NENs.C-index was used for assessing the predictive effectiveness.We conducted a subgroup analysis to explore the different lymph node staging systems’predictive values.RESULTS After adjusting all confounding factors,PLN,LNR and LODDS staging systems were linked with mortality in patients with colorectal NENs treated surgically(P<0.05).We found that LODDS staging had a higher prognostic value for patients with colorectal NENs treated surgically than PLN and LNR staging systems.Similar results were obtained in the different G staging subgroup analyses.Furthermore,the area under the receiver operating characteristic curve values for LODDS staging system remained consistently higher than those of PLN or LNR,even at the 1-,2-,3-,4-,5-and 6-year follow-up periods.CONCLUSION LNR,PLN,and LODDS were found to significantly predict the prognosis of patients with colorectal NENs treated surgically.

Tumour response following preoperative chemotherapy is affected by body mass index in patients with colorectal liver metastases

BACKGROUND Colorectal cancer is the third most prevalent malignancy globally and ranks second in cancer-related mortality,with the liver being the primary organ of metastasis.Preoperative chemotherapy is widely recommended for initially or potentially resectable colorectal liver metastases(CRLMs).Tumour pathological response serves as the most important and intuitive indicator for assessing the efficacy of chemotherapy.However,the postoperative pathological results reveal that a considerable number of patients exhibit a poor response to preoperative chemotherapy.Body mass index(BMI)is one of the factors affecting the tumori-genesis and progression of colorectal cancer as well as prognosis after various antitumour therapies.Several studies have indicated that overweight and obese patients with metastatic colorectal cancer experience worse prognoses than those with normal weight,particularly when receiving first-line chemotherapy regimens in combination with bevacizumab.AIM To explore the predictive value of BMI regarding the pathologic response following preoperative chemotherapy for CRLMs.METHODS A retrospective analysis was performed in 126 consecutive patients with CRLM who underwent hepatectomy following preoperative chemotherapy at four different hospitals from October 2019 to July 2023.Univariate and multivariate logistic regression models were applied to analyse potential predictors of tumour pathological response.The Kaplan-Meier method with log rank test was used to compare progression-free survival(PFS)between patients with high and low BMI.BMI<24.0 kg/m^(2) was defined as low BMI,and tumour regression grade 1-2 was defined as complete tumour response.RESULTS Low BMI was observed in 74(58.7%)patients and complete tumour response was found in 27(21.4%)patients.The rate of complete tumour response was significantly higher in patients with low BMI(29.7%vs 9.6%,P=0.007).Multivariate analysis revealed that low BMI[odds ratio(OR)=4.56,95%confidence interval(CI):1.42-14.63,P=0.011],targeted therapy with bevacizumab(OR=3.02,95%CI:1.10-8.33,P=0.033),preoperative carcinoembryonic antigen level<10 ng/mL(OR=3.84,95%CI:1.19-12.44,P=0.025)and severe sinusoidal dilatation(OR=0.17,95%CI:0.03-0.90,P=0.037)were independent predictive factors for complete tumour response.The low BMI group exhibited a significantly longer median PFS than the high BMI group(10.7 mo vs 4.7 mo,P=0.011).CONCLUSION In CRLM patients receiving preoperative chemotherapy,a low BMI may be associated with better tumour response and longer PFS.

Comparative effectiveness of immunotherapy and chemotherapy in patients with metastatic colorectal cancer stratified by microsatellite instability status

BACKGROUND Immunotherapy have demonstrated promising outcomes in patients with high microsatellite instability(MSI)(MSI-H)metastatic colorectal cancer.However,the comparative effectiveness of Immunotherapy and chemotherapy for patients with low MSI(MSI-L),and microsatellite stable(MSS)metastatic colorectal cancer remains unclear.AIM To investigate immunotherapy vs chemotherapy for treatment of MSI-L/MSS metastatic colorectal cancer,and to evaluate the success of immunotherapy against chemotherapy in managing MSI-H metastatic colorectal cancer during a follow-up of 50 months.METHODS We conducted a retrospective cohort study using the National Cancer Database(NCDB)to evaluate the overall survival(OS)of patients with metastatic colorectal cancer treated with immunotherapy or chemotherapy.The study population was stratified by MSI status(MSI-H,MSI-L,and MSS).Multivariable Cox proportional hazard models were used to assess the association between treatment modality and OS,adjusting for potential confounders.RESULTS A total of 21951 patients with metastatic colorectal cancer were included in the analysis,of which 2358 were MSI-H,and 19593 were MSI-L/MSS.In the MSI-H cohort,immunotherapy treatment(n=142)was associated with a significantly improved median OS compared to chemotherapy(n=860).After adjusting for potential confounders,immunotherapy treatment remained significantly associated with better OS in the MSI-H cohort[adjusted hazard ratio(aHR):0.57,95%confidence interval(95%CI):0.43-0.77,P<0.001].In the MSS cohort,no significant difference in median OS was observed between immunotherapy treatment and chemotherapy(aHR:0.94,95%CI:0.69-1.29,P=0.715).CONCLUSION In this population-based study using the NCDB,immunotherapy treatment was associated with significantly improved OS compared to chemotherapy in patients with MSI-H metastatic colorectal cancer,but not in those with MSI-L/MSS metastatic colorectal cancer.Further studies are warranted to determine the optimal therapeutic approach for patients with MSI-L/MSS metastatic colorectal cancer.

Symptom Experience and Quality of Life in Colorectal Cancer Patients Undergoing Chemotherapy-A Secondary Publication

Objective:To evaluate symptom experience and quality of life(QoL)and to identify the predictors of QoL among colorectal cancer patients undergoing chemotherapy.Methods:A cross-sectional study was conducted on 107 colorectal cancer patients at a university-affiliated hospital between June 1 and July 30,2021.Functional Assessment of Cancer Therapy-Colorectal(FACT-C)and Memorial Symptom Assessment Scale-Short Form(MSAS-SF)were used to assess symptom experience and QoL of these patients.Data were analyzed using Pearson’s correlation,t-test,ANOVA,and hierarchical multiple regression.Results:The mean QoL score for colorectal cancer patients was 88.78±20.08.The most frequently experienced physical and psychological symptoms were numbness/tingling and worrying.Physical and psychological symptoms have a significant negative association with QoL.Perceived economic status was significantly associated with QoL in patients’general characteristics.The regression analyses showed that high psychological symptoms(β=-0.63,P<0.001),middle perceived economic status(β=-0.22,P=0.009),and low perceived economic status(β=-0.36,P<0.001)were statistically significant in predicting patients’low QoL.Conclusion:Symptom experience and QoL are essential variables that should be acknowledged when delivering health care to colorectal cancer patients.More attention to the reduction and comprehensive symptom management of psychological distress could improve QoL among colorectal cancer patients.

Synchronous manifestation of colorectal cancer and intraductal papillary mucinous neoplasms

High rates of extrapancreatic malignancies,in particular colorectal cancer(CRC),have been detected in patients with intraductal papillary mucinous neoplasm(IPMN).So far,there is no distinct explanation in the literature for the development of secondary or synchronous malignancies in patients with IPMN.In the past few years,some data related to common genetic alterations in IPMN and other affiliated cancers have been published.This review elucidated the association between IPMN and CRC,shedding light on the most relevant genetic alterations that may explain the possible relationship between these entities.In keeping with our findings,we suggested that once the diagnosis of IPMN is made,special consideration of CRC should be undertaken.Presently,there are no specific guidelines regarding colorectal screening programs for patients with IPMN.We recommend that patients with IPMNs are at high-risk for CRC,and a more rigorous colorectal surveillance program should be implemented.

Anti-EGFR antibody monotherapy for colorectal cancer with severe hyperbilirubinemia: A case report

BACKGROUND Hyperbilirubinemia with hepatic metastases is a common complication and a poor prognostic factor for colorectal cancer(CRC).Effective drainage is often im-possible before initiating systemic chemotherapy,owing to the liver’s diffuse metastatic involvement.Moreover,an appropriate chemotherapeutic approach for the treatment of hyperbilirubinemia is currently unavailable.CASE SUMMARY The patient,a man in his 50s,presented with progressive fatigue and severe jaundice.Computed tomography revealed multiple hepatic masses with thick-ened walls in the sigmoid colon,which was pathologically confirmed as a well-differentiated adenocarcinoma.No RAS or BRAF mutations were detected.The Eastern Cooperative Oncology Group(ECOG)performance status(PS)score was 2.Biliary drainage was impossible due to the absence of a dilated bile duct,and panitumumab monotherapy was promptly initiated.Subsequently,the bilirubin level decreased and then normalized,and the patient’s PS improved to zero ECOG score after four cycles of therapy without significant adverse events.CONCLUSION Anti-EGFR antibody monotherapy is a safe and effective treatment for RAS wild-type CRC and hepatic metastases with severe hyperbilirubinemia.

Improving the value of molecular testing:current status and opportunities in colorectal cancer precision medicine

Colorectal cancer(CRC)is the second leading cause of cancer-related deaths worldwide1.Surgical radical resection with adjuvant chemotherapy remains the primary treatment choice for CRC,but the 5-year postoperative survival rate is only approximately 60%,and approximately one-third of patients with CRC experience recurrence within 2 years of surgery2.Fortunately,the transformation of high-throughput sequencing has accelerated the development of precision medicine.For example,KRAS mutations indicate resistance to anti-epidermal growth factor receptor(EGFR)-targeted therapies in CRC3.Furthermore,molecular-guided individualized therapy has brought new promise in major clinical areas and challenges,such as novel biomarkers predicting sensitivity and resistance to immunotherapy for microsatellite stable(MSS)CRC.

Recent clinical trials and optical control as a potential strategy to develop microtubule-targeting drugs in colorectal cancer management

Colorectal cancer(CRC)has remained the second and the third leading cause of cancer-related death worldwide and in the United States,respectively.Although significant improvement in overall survival has been achieved,death in adult populations under the age of 55 appears to have increased in the past decades.Although new classes of therapeutic strategies such as immunotherapy have emerged,their application is very limited in CRC so far.Microtubule(MT)inhibitors such as taxanes,are not generally successful in CRC.There may be some way to make MT inhibitors work effectively in CRC.One potential advantage that we can take to treat CRC may be the combination of optical techniques coupled to an endoscope or other fiber optics-based devices.A combination of optical devices and photo-activatable drugs may allow us to locally target advanced CRC cells with highly potent MT-targeting drugs.In this Editorial review,we would like to discuss the potential of optogenetic approaches in CRC management.

Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?

BACKGROUND Colorectal cancer(CRC)is a global health concern,with advanced-stage diagnoses contributing to poor prognoses.The efficacy of CRC screening has been well-established;nevertheless,a significant proportion of patients remain unscreened,with>70%of cases diagnosed outside screening.Although identifying specific subgroups for whom CRC screening should be particularly recommended is crucial owing to limited resources,the association between the diagnostic routes and identification of these subgroups has been less appreciated.In the Japanese cancer registry,the diagnostic routes for groups discovered outside of screening are primarily categorized into those with comorbidities found during hospital visits and those with CRC-related symptoms.AIM To clarify the stage at CRC diagnosis based on diagnostic routes.METHODS We conducted a retrospective observational study using a cancer registry of patients with CRC between January 2016 and December 2019 at two hospitals.The diagnostic routes were primarily classified into three groups:Cancer screening,follow-up,and symptomatic.The early-stage was defined as Stages 0 or I.Multivariate and univariate logistic regressions were exploited to determine the odds of early-stage diagnosis in the symptomatic and cancer screening groups,referencing the follow-up group.The adjusted covariates were age,sex,and tumor location.RESULTS Of the 2083 patients,715(34.4%),1064(51.1%),and 304(14.6%)belonged to the follow-up,symptomatic,and cancer screening groups,respectively.Among the 2083 patients,CRCs diagnosed at an early stage were 57.3%(410 of 715),23.9%(254 of 1064),and 59.5%(181 of 304)in the follow-up,symptomatic,and cancer screening groups,respectively.The symptomatic group exhibited a lower likelihood of early-stage diagnosis than the follow-up group[P<0.001,adjusted odds ratio(aOR),0.23;95%confidence interval(95%CI):0.19-0.29].The likelihood of diagnosis at an early stage was similar between the follow-up and cancer screening groups(P=0.493,aOR for early-stage diagnosis in the cancer screening group vs follow-up group=1.11;95%CI=0.82-1.49).CONCLUSION CRCs detected during hospital visits for comorbidities were diagnosed earlier,similar to cancer screening.CRC screening should be recommended,particularly for patients without periodical hospital visits for comorbidities.

Value of glucose transport protein 1 expression in detecting lymph node metastasis in patients with colorectal cancer

BACKGROUND There are limited data on the use of glucose transport protein 1(GLUT-1)expre-ssion as a biomarker for predicting lymph node metastasis in patients with colorectal cancer.GLUT-1 and GLUT-3,hexokinase(HK)-II,and hypoxia-induced factor(HIF)-1 expressions may be useful biomarkers for detecting primary tumors and lymph node metastasis when combined with fluorodeoxyglucose(FDG)uptake on positron emission tomography/computed tomography(PET/CT).AIM To evaluate GLUT-1,GLUT-3,HK-II,and HIF-1 expressions as biomarkers for detecting primary tumors and lymph node metastasis with 18F-FDG-PET/CT.METHODS This retrospective study included 169 patients with colorectal cancer who underwent colectomy and preoperative 18F-FDG-PET/CT at Chungbuk National University Hospital between January 2009 and May 2012.Two tissue cores from the central and peripheral areas of the tumors were obtained and were examined by a dedicated pathologist,and the expressions of GLUT-1,GLUT-3,HK-II,and HIF-1 were determined using immunohisto-chemical staining.We analyzed the correlations among their expressions,various clinicopathological factors,and the maximum standardized uptake value(SUVmax)of PET/CT.RESULTS GLUT-1 was found at the center or periphery of the tumors in 109(64.5%)of the 169 patients.GLUT-1 positivity was significantly correlated with the SUVmax of the primary tumor and lymph nodes,regardless of the biopsy site(tumor center,P<0.001 and P=0.012;tumor periphery,P=0.030 and P=0.010,respectively).GLUT-1 positivity and negativity were associated with higher and lower sensitivities of PET/CT,respectively,for the detection of lymph node metastasis,regardless of the biopsy site.GLUT3,HK-II,and HIF-1 expressions were not significantly correlated with the SUVmax of the primary tumor and lymph nodes.CONCLUSION GLUT-1 expression was significantly correlated with the SUVmax of 18F-FDG-PET/CT for primary tumors and lymph nodes.Clinicians should consider GLUT-1 expression in preoperative endoscopic biopsy in interpreting PET/CT findings.

Role of targeting ferroptosis as a component of combination therapy in combating drug resistance in colorectal cancer

Colorectal cancer(CRC)is a form of cancer that is often resistant to chemotherapy,targeted therapy,radiotherapy,and immunotherapy due to its genomic instability and inflammatory tumor microenvironment.Ferroptosis,a type of non-apoptotic cell death,is characterized by the accumulation of iron and the oxidation of lipids.Studies have revealed that the levels of reactive oxygen species and glutathione in CRC cells are significantly lower than those in healthy colon cells.Erastin has emerged as a promising candidate for CRC treatment by diminishing stemness and chemoresistance.Moreover,the gut,responsible for regulating iron absorption and release,could influence CRC susceptibility through iron metabolism modulation.Investigation into ferroptosis offers new insights into CRC pathogenesis and clinical management,potentially revolutionizing treatment approaches for therapy-resistant cancers.

Is the combination of immunotherapy with conventional chemotherapy the key to increase the efficacy of colorectal cancer treatment?

Colorectal cancer(CRC) is among the most prevalent and deadly neoplasms worldwide. According to GLOBOCAN predictions, its incidence will increase from 1.15 million CRC cases in 2020 to 1.92 million cases in 2040. Therefore, a better understanding of the mechanisms involved in CRC development is necessary to improve strategies focused on reducing the incidence, prevalence,and mortality of this oncological pathology. Surgery, chemotherapy, and radiotherapy are the main strategies for treating CRC. The conventional chemotherapeutic agent utilized throughout the last four decades is 5-fluorouracil, notwithstanding its low efficiency as a single therapy. In contrast, combining 5-fluorouracil therapy with leucovorin and oxaliplatin or irinotecan increases its efficiency. However, these treatments have limited and temporary solutions and aggressive side effects. Additionally, most patients treated with these regimens develop drug resistance, which leads to disease progression. The immune response is considered a hallmark of cancer;thus, the use of new strategies and methodologies involving immune molecules, cells, and transcription factors has been suggested for CRC patients diagnosed in stages Ⅲ and Ⅳ. Despite the critical advances in immunotherapy, the development and impact of immune checkpoint inhibitors on CRC is still under investigation because less than 25% of CRC patients display an increased 5-year survival. The causes of CRC are diverse and include modifiable environmental factors(smoking, diet, obesity, and alcoholism), individual genetic mutations, and inflammation-associated bowel diseases. Due to these diverse causes, the solutions likely cannot be generalized. Interestingly, new strategies, such as single-cell multiomics, proteomics, genomics, flow cytometry, and massive sequencing for tumor microenvironment analysis, are beginning to clarify the way forward. Thus,the individual mechanisms involved in developing the CRC microenvironment, their causes, and their consequences need to be understood from a genetic and immunological perspective. This review highlighted the importance of altering the immune response in CRC. It focused on drugs that may modulate the immune response and show specific efficacy and contrasted with evidence that immunosuppression or the promotion of the immune response is the answer to generating effective treatments with combined chemotherapeutic drugs.

Risk factors for bleeding after endoscopic submucosal dissection of colorectal neoplasms

AIM:To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection(ESD)treatment for colorectal neoplasms.METHODS:We retrospectively reviewed the medical records of 317 consecutive patients with 325 lesions who underwent ESD for superficial colorectal neoplasms at our hospital from January 2009 to June2013.Delayed post-ESD bleeding was defined as bleeding that resulted in overt hematochezia 6 h to 30d after ESD and the observation of bleeding spots as confirmed by repeat colonoscopy or a required blood transfusion.We analyzed the relationship between risk factors for delayed bleeding following ESD and the following factors using univariate and multivariate analyses:age,gender,presence of comorbidities,use of antithrombotic drugs,use of intravenous heparin,resected specimen size,lesion size,lesion location,lesion morphology,lesion histology,the device used,procedure time,and the presence of significant bleeding during ESD.RESULTS:Delayed post-ESD bleeding was found in14 lesions from 14 patients(4.3%of all specimens,4.4%patients).Patients with episodes of delayed postESD bleeding had a mean hemoglobin decrease of2.35 g/dL.All episodes were treated successfully using endoscopic hemostatic clips.Emergency surgery was not required in any of the cases.Blood transfusion was needed in 1 patient(0.3%).Univariate analysis revealed that lesions located in the cecum(P=0.012)and the presence of significant bleeding during ESD(P=0.024)were significantly associated with delayed post-ESD bleeding.The risk of delayed bleeding was higher for larger lesion sizes,but this trend was not statistically significant.Multivariate analysis revealed that lesions located in the cecum(OR=7.26,95%CI:1.99-26.55,P=0.003)and the presence of significant bleeding during ESD(OR=16.41,95%CI:2.60-103.68,P=0.003)were independent risk factors for delayed post-ESD bleeding.CONCLUSION:Location in the cecum and significant bleeding during ESD predispose patients to delayed post-procedural bleeding.Therefore,careful and additional management is recommended for these patients.

Endoscopic submucosal dissection for colorectal neoplasms

Although endoscopic submucosal dissection(ESD) gains acceptance as one of the standard treatments for esophageal and stomach neoplasms in Japan,it is still in the developing stage for colorectal neoplasms.In terms of indications,little likelihood of nodal metastasis and technical resectability are principally considered.Some of intramucosal neoplasms,carcinomas with minute submucosal invasion,and carcinoid tumors,which are technically unresectable by conventional endoscopic treatments,may become good candidates for ESD,considering substantial risks and obtained benefits.ESD as a staging measure to obtain histological information of the invasion depth and lymphovascular infiltration is acceptable because preoperative prediction is difficult in some cases.In terms of techniques,advantages of ESD in comparison with other endoscopic treatments are to be controllable in size and shape,and to be resectable even in large and fibrotic neoplasms.The disadvantages may be longer procedure time,heavier bleeding,and higher possibility of perforation.However,owing to refinement of the techniques,invention of devices,and the learning curve,acceptable technical safety has been achieved.Colorectal ESD is very promising and become one of the standard treatments for colorectal neoplasms in the near future.

Association between white opaque substance under magnifying colonoscopy and lipid droplets in colorectal epithelial neoplasms

AIM To examine the association between white opaque substance(WOS) and histologically verified lipiddroplets in colorectal epithelial neoplasms.METHODS We reviewed colonoscopy records at our institution from 2014 to 2016 and identified cases of endoscopically or surgically resected colorectal epithelial neoplasms observed by magnifying narrow-band imaging(M-NBI) colonoscopy. Immunohistochemistry was used to stain tumors with a monoclonal antibody specific to adipophilin as a marker of lipids. The expression and distribution of adipophilin were compared between WOS-positive and WOS-negative lesions and among tumors classified by histologic type and depth of invasion.RESULTS Under M-NBI colonoscopy, 81 lesions were positive for WOS and 48 lesions were negative for WOS. The rate of adipophilin expression was significantly higher in WOS-positive lesions(95.1%) than in WOS-negative lesions(68.7%)(P = 0.0001). The incidence of deep adipophilin expression was higher in WOS-positive lesions(24.7%) than in WOS-negative lesions(4.2%)(P = 0.001). The incidence of deep expression was predominant among cancers with massive submucosal invasion(62.5%) compared to adenoma(7.2%) and high-grade dysplasia or cancers with slight submucosal invasion(12.7%)(P = 0.0001).CONCLUSION The distribution of lipid droplets may be closely associated with the visibility of WOS under M-NBI colonoscopy, and with histologic grade and depth of tumor invasion.

Clinical significance of type V_I pit pattern subclassification in determining the depth of invasion of colorectal neoplasms

AIM: To clarify whether subclassification of the type VI pit pattern on the basis of magnifying colonoscopy findings is useful in determining the type and depth of invasion of colorectal neoplasms.METHODS: We retrospectively analyzed 272 colorectal neoplasms (117 dysplasias and 155 submucosal invasive carcinomas; 228 patients) with a type V pit pattern [type VI, n = 202; type VN, n = 70 (Kudo and Tsuruta classification system)]. We divided lesions with a type VI pit pattern into two subclasses, mildly irregular lesions and severely irregular lesions, according to the prominent and detailed magnifying colonoscopy findings. We examined the relation between these two subclasses and histology/invasion depth.RESULTS: One hundred and four lesions (51.5%) were judged to be mildly irregular, and 98 lesions (48.5%) were judged to be severely irregular. Ninety-seven (93.3%) mildly irregular lesions showed dysplasias or submucosal invasion of less than 1000 μm (SM < 1000 μm). Fifty-five (56.1%) severely irregular lesions showed submucosal invasion equal to or deeper than 1000 μm (SM ≥ 1000 μm). Mild irregularity was found significantly more often in dysplasias or lesions with SM < 1000 μm than in lesions with SM ≥ 1000 μm (P < 0.01).CONCLUSION: Subclassification of the type VI pit pattern is useful for identifying dysplasias or lesions with SM < 1000 μm.

CYP1A1,CYP2E1 and EPHX1 polymorphisms in sporadic colorectal neoplasms

AIM To investigate the contribution of polymorphisms in the CYP1A1, CYP2E1 and EPHX1 genes on sporadic colorectal cancer(SCRC) risk. METHODS Six hundred forty-one individuals(227 patients with SCRC and 400 controls) were enrolled in the study. The variables analyzed were age, gender, tobacco and alcohol consumption, and clinical and histopathological tumor parameters. The CYP1A1 *2A, CYP1A1 *2C CYP2E1 *5B and CYP2E1 *6 polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP). The EPHX1 Tyr113 His, EPHX1 His139 Arg and CYP1A1 *2C polymorphisms were detected by real-time PCR. Chisquared test and binary logistic regression were used in the statistical analysis. Haplotype analysis was conducted using the Haploview program, version 2.05.RESULTS Age over 6 2 years was a risk factor for SCRC development(OR = 7.54, 95%CI: 4.94-11.50, P < 0.01). Male individuals were less susceptible to SCRC(OR = 0.55, 95%CI: 0.35-0.85, P < 0.01). The CYP2E1*5B polymorphism was associated with SCRC in the codominant(heterozygous genotype: OR = 2.66, 95%CI: 1.64-4.32, P < 0.01), dominant(OR = 2.82, 95%CI: 1.74-4.55, P < 0.01), overdominant(OR = 2.58, 95%CI: 1.59-4.19, P < 0.01), and log-additive models(OR = 2.84, 95%CI: 1.78-4.52, P < 0.01). The CYP2E1*6 polymorphism was associated with an increased SCRC risk in codominant(heterozygous genotype: OR = 2.81, 95%CI: 1.84-4.28, P < 0.01; homozygous polymorphic : OR = 7. 3 2, 9 5 % C I : 1.85-28.96, P < 0.01), dominant(OR = 2.97, 95%CI: 1.97-4.50, P < 0.01), recessive(OR = 5.26, 95%CI: 1.35-20.50, P = 0.016), overdominant(OR = 2.64, 95%CI: 1.74-4.01, P < 0.01), and log-additive models(OR = 2.78, 95%CI: 1.91-4.06, P < 0.01). The haplotype formed by the minor alleles of the CYP2E1*5B(C) and CYP2E1*6(A) polymorphisms was associated with SCRC(P = 0.002). However, the CYP1A1 *2A, CYP1A1 *2C, EPHX1 Tyr113 His and EPHX1 His139 Arg polymorphisms were not associated with SCRC.CONCLUSION In conclusion, the results demonstrated that CYP2E1*5B and CYP2E1*6 minor alleles play a role in the development of SCRC.

Incidence and localization of lymphoid follicles in early colorectal neoplasms

AIM: To investigate the incidence and localizations of lymphoid follicles (LFs) in early colorectal neoplasms in human beings.METHODS: From July 1992 to September 1999, a total of 1 324 early colorectal neoplasms were removed endoscopically or surgically at our hospital; 1 031 (77.9%)were available for analysis in this study. Localization of LFs was defined histologically: as submucosal LFs, if located under the muscularis mucosa; and as intramucosal LFs, if located across or oyer the muscularis mucosa.RESULTS: Histologically, the materials included 903intramucosal neoplasms and 128 submucosal cancers.Overall incidence of LFs was 27.2% (280/1 031). The incidence of LFs was significantly higher in females (33.6% vs 24.9%,P=0.0064), the right-sided colon (32.2% vs 25.6%, P=0.0403) and in flat or depressed type lesions (34.6% vs 25.2%, P＜0.0001)as compared to males, left-sided colon and protruding type lesions, respectively. The incidences of intramucosal neoplasms and submucosal cancers were 24.3% and 43.8%, respectively (P＜0.0001). Localizations of LFs (intramucosal LF/submucosal LF) in depressed, flat,and protruding types were 1/24, 14/36, and 131/74,respectively.CONCLUSION: The incidence of LFs in early human colorectal neoplasms significantly differs by gender,location, macroscopic type, and histology. Moreover,localization significantly differs by macroscopic type.

Incidence of colorectal neoplasms among male pilots

AIM: To assess the prevalence of colorectal neoplasms(adenomas, advanced adenomas and colorectal cancers) among Israeli military and commercial airline pilots.METHODS: Initial screening colonoscopy was performed on average-risk(no symptoms and no family history) airline pilots at the Integrated Cancer Prevention Center(ICPC) in the Tel-Aviv Medical Center. Visualized polyps were excised and sent for pathological examination. Advanced adenoma was defined as a lesion >10 mm in diameter, with high-grade dysplasia or villous histology. The results were compared with those of an age- and gender-matched random sample of healthy adults undergoing routine screening at the ICPC.RESULTS: There were 270 pilots(mean age 55.2 ± 7.4 years) and 1150 controls(mean age 55.7 ± 7.8 years). The prevalence of colorectal neoplasms was 15.9% among the pilots and 20.6% among the controls(P = 0.097, χ2 test). There were significantly more hyperplastic polyps among pilots(15.5% vs 9.4%, P = 0.004) and a trend towards fewer adenomas(14.8% vs 20.3% P = 0.06). The prevalence of advanced lesions among pilots and control groups was 5.9% and 4.7%, respectively(P = 0.49), and the prevalence of cancer was 0.7% and 0.69%, respectively(P = 0.93).CONCLUSION: There tends to be a lower colorectal adenoma, advanced adenoma and cancer prevalence but a higher hyperplastic polyp prevalence among pilots than the general population.