The first year follow-up after colorectal adenoma polypectomy is important: a multiple-center study in symptomatic hospital-based individuals in China. ACTA ACUST UNITED AC. 2010;4:436-442. [PMID: 21128011 DOI: 10.1007/s11684-010-0200-9]

Chinese national clinical practice guidelines on prevention, diagnosis and treatment of early colorectal cancer

BACKGROUND

The incidence and mortality of colorectal cancer (CRC) in China are increasing in recent years. The clarified pathogenesis and detectable precancerous lesions of CRC make it possible to prevent, screen, and diagnose CRC at an early stage. With the development of endoscopic and surgical techniques, the choice of treatment for early CRC is also worth further discussion, and accordingly, a standard follow-up program after treatment needs to be established.

METHODS

This clinical practice guideline (CPG) was developed following the recommended process of the World Health Organization, adopting Grading of Recommendations Assessment, Development and Evaluation (GRADE) in assessing evidence quality, and using the Evidence to Decision framework to formulate clinical recommendations, thereby minimizing bias and increasing transparency of the CPG development process. We used the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement and Appraisal of Guidelines for Research and Evaluation II (AGREE II) as reporting and conduct guides to ensure the guideline's completeness and transparency.

RESULTS

This CPG comprises 46 recommendations concerning prevention, screening, diagnosis, treatment, and surveillance of CRC. In these recommendations, we have indicated protective and risk factors for CRC and made recommendations for chemoprevention. We proposed a suitable screening program for CRC based on the Chinese context. We also provided normative statements for the diagnosis, treatment, and surveillance of CRC based on existing clinical evidence and guidelines.

CONCLUSIONS

The 46 recommendations in this CPG are formed with consideration for stakeholders' values and preferences, feasibility, and acceptability. Recommendations are generalizable to resource-limited settings with similar CRC epidemiology pattern as China.

Efficacy and safety of Shenbai Granules for recurrent colorectal adenoma: A multicenter randomized controlled trial

BACKGROUND

Colorectal adenoma is benign glandular tumor of colon, the precursor of colorectal cancer. But no pharmaceutical medication is currently available to treat and prevent adenomas.

PURPOSE

To evaluate efficacy of Shenbai Granules, an herbal medicine formula, in reducing the recurrence of adenomas.

STUDY DESIGN

This multicenter, randomized, double-blind, placebo-controlled clinical trial was conducted by eight hospitals in China.

METHODS

Patients who had received complete polypectomy and were diagnosed with adenomas within the recent 6 months were randomly assigned (1:1) to receive either Shenbai granules or placebo twice a day for 6 months. An annual colonoscopy was performed during the 2-year follow-up period. The primary outcome was the proportion of patients with at least one adenoma detected in the modified intention-to-treat (mITT) population during follow-up for 2 years. The secondary outcomes were the proportion of patients with sessile serrated lesions and other specified polypoid lesions. The data were analyzed using logistic regression.

RESULTS

Among 400 randomized patients, 336 were included in the mITT population. We found significant differences between treatment and placebo groups in the proportion of patients with at least one recurrent adenoma (42.5 % vs. 58.6 %; OR, 0.47; 95 % CI, 0.29-0.74; p = 0.001) and sessile serrated lesion (1.8 % vs. 8.3 %; OR, 0.20; 95 % CI, 0.06-0.72; p = 0.01). There was no significant difference in the proportion of patients developing polypoid lesions (70.7 % vs. 77.5 %; OR, 1.43; 95 % CI, 0.88-2.34; p = 0.15) or high-risk adenomas (9.0 % vs. 13.6 %; OR, 0.63; 95 % CI, 0.32-1.25; p = 0.18).

CONCLUSION

Shenbai Granules significantly reduced the recurrence of adenomas, indicating that they could be an effective option for adenomas. Future studies should investigate its effects in larger patient populations and explore its mechanism of action to provide more comprehensive evidence for the use of Shenbai Granules in adenoma treatment.

Preventive effects of chemical drugs on recurrence of colorectal adenomas: systematic review and Bayesian network meta-analysis

BACKGROUND

The onset of colorectal adenomas (CRAs) is significantly associated with colorectal cancer. The preventive effects of chemical drugs on the recurrence of CRAs have been evaluated in a large number of randomized controlled trials (RCTs). However, there are still uncertainties about the relative effectiveness of such chemical drugs.

METHODS

We searched relevant RCTs published in six databases up to February 2023. The quality of the included studies was assessed by using the Cochrane risk of bias assessment tool and Review Manager 5.4. Pairwise comparison and network meta-analysis (NMA) were conducted using RStudio to compare the effects of chemical drugs on the recurrence of CRAs.

RESULTS

Forty-five high-quality RCTs were included. A total of 35 590 (test group: 20 822; control group: 14 768) subjects with a history of CRAs have been enrolled and randomized to receive placebo treatment or one of 24 interventions. Based on surface under the cumulative ranking values and NMA results, difluoromethylornithine (DFMO) + Sulindac significantly reduced the recurrence of CRAs, followed by berberine and nonsteroidal antiinflammatory drugs.

CONCLUSION

DFMO + Sulindac is more effective in reducing the recurrence of CRAs but has a high risk of adverse events. Considering drug safety, tolerance, and compliance, berberine has a brighter prospect of clinical development. However, further studies are needed to verify our findings.

Does Chinese herbal medicine (CHM) reduce colorectal adenoma (CRA) recurrence: protocol of a registry-based, cohort study and a qualitative interview

INTRODUCTION

Colorectal adenoma (CRA) is a precancerous lesion for colorectal cancer. Endoscopic resection is the first-line treatment for CRA. However, CRA recurrence rate is high. This proposed study aims to determine if Chinese herbal medicine (CHM) reduces CRA recurrence.

METHODS AND ANALYSIS

This project encompasses an observational, registry-based, cohort study and a nested qualitative study. The cohort study aims to include 364 postpolypectomy CRA participants at Guangdong Provincial Hospital of Chinese Medicine (GPHCM), China, with a follow-up phase of up to 1 year. In addition to routine care, these participants will receive a CHM treatment prescribed by experienced Chinese medicine (CM) clinicians. The CHM treatment encompasses CHM products and CHM formulae according to CM syndromes. The primary outcome is CRA recurrence rate at 1 year after enrolment. Secondary outcomes include characteristics of recurrent CRA, incidence of colorectal polyp (except for CRA), incidence of advanced CRA, incidence of colorectal cancer, improvement of gastrointestinal symptoms commonly seen in CRA patients, faecal occult blood test result, lipid level, fasting plasma glucose level, uric acid level, carcinoembryonic antigen, carbohydrate antigen 19-9, quality of life and safety evaluations. Logistic regression analysis will be used to explore the correlation between exposure and outcome. Qualitative interviews will be conducted among approximate 30 CRA patients from the cohort study and 10 CM practitioners in Department of Gastroenterology at GPHCM. Thematic analysis will be used to analyse qualitative data.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Human Research Ethics Committee (HREC) of GPHCM (YF2022-320-02) and registered at Royal Melbourne Institute of Technology (RMIT) HREC. The results will be disseminated in peer-reviewed journals and international academic conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200065713.

Eflornithine for chemoprevention in the high-risk population of colorectal cancer: a systematic review and meta-analysis with trial sequential analysis

Objectives

To evaluate the efficacy of Difluoromethylornithine (DFMO) chemoprevention in the high-risk population for colorectal cancer (CRC).

Methods

Meta-analysis was conducted to assess the caliber of the included literature by searching five databases for randomized controlled trials of DFMO chemoprevention in the high-risk population of CRC, with RevMan 5.4, Stata 15.0 and TSA 0.9.5.10 employed to statistically analyze the extracted data. Grade profiler 3.6 was employed for grading the evidence for the outcome indicators (disease progression and adenoma incidence).

Results

Six trials were finally included in this research, with the collective data indicating that the DFMO combination therapy was efficacious in lowering the incidence of recurrent adenomas in patients who had experienced advanced CRC [RR 0.34, 95% CI 0.14 - 0.83, P < 0.05]. Meta-analysis showed that DFMO combined therapy had no statistical difference in disease progression in patients with familial adenomatous polyposis[RR 0.52, 95% CI 0.14 - 1.86, P > 0.05]; Trial Sequential Analysis reveals that the combination therapy of DFMO effectively diminishes the occurrence of recurrent adenomas in patients with a history of advanced colorectal tumors, displaying a Risk Ratio (RR) of 0.33 with a 95% Confidence Interval (CI) of 0.12 - 0.90 and a significance level of P < 0.05. This combination exhibits a statistically significant difference. Subgroup analysis demonstrates that, depending on the drug treatment regimen (DFMO+ Aspirin/DFMO+ Sulindac), the combination of DFMO and aspirin exhibits an effect comparable to a placebo in diminishing the occurrence of new adenomas in patients with a history of advanced colorectal tumors. However, the combination of DFMO and sulindac significantly mitigates the incidence of recurrent adenomas in this patient population.

Conclusion

This meta-analysis indicates that the existing randomized controlled trials are adequate to ascertain the efficacy of DFMO combination therapy in diminishing the incidence of recurrent adenomas in patients who have previously encountered advanced colorectal tumors. However, further clinical trials need to be conducted to evaluate the optimum dosage and treatment course of prophylactic implementation of DFMO combination therapy in high-risk populations.

Oral Chinese herbal medicine in reducing the recurrence of colorectal adenoma after polypectomy: A protocol for the systematic review and meta-analysis

BACKGROUND

Colorectal adenoma (CRA) is a significant precancerous lesion of sporadic colorectal cancer (CRC). CRA is likely to recur after polypectomy, increasing the risk of CRC. Chinese herbal medicine (CHM) has been used to reduce CRA recurrence. This review aims to evaluate the effectiveness and safety of oral CHM in reducing CRA recurrence compared to other treatments (placebo, routine care, no treatment, and conventional medicine).

METHODS

We will search for randomised controlled trials (RCTs) from nine major biomedical databases in English and Chinese from their inception to July 2023. The RCTs that investigate the effects of oral CHM in reducing CRA recurrence compared to other treatments will be involved. We will exclude trials using CHM extract or external application of CHM, cohort study and cross-section study. The Cochrane Risk of Bias Tool version 2 will be used to assess the quality of included studies. Data will be analysed using Review Manager software 5.4 and STATA. The random effect model will be used. The heterogeneity of intervention effects will be tested by Chi2 (Cochrane Q) and I2 statistics. Funnel plots will assess publication bias if more than ten studies are included. Subgroup and sensitivity analysis will be conducted when possible.

DISCUSSION

This review will discuss the effectiveness and safety of oral CHM in reducing CRA recurrence. It will show the critical information for clinicians in the decision-making process and countries to develop clinical guidelines on CRA management. Systematic review registration PROSPERO CRD42023324197.

Sijunzi decoction granules in the prevention and treatment of recurrence of colorectal adenoma: Study protocol for a multicenter, randomized, double-blind, placebo-controlled trial

Background: The recurrence of colorectal adenomas (CRAs) after endoscopy predisposes patients to a risk of colorectal cancer. Guided by the traditional Chinese medicine (TCM), patients with colorectal diseases usually manifest with spleen deficiency syndrome (SDS) and are treated with Sijunzi decoction (SJZD). Therefore, this trial aims to explore the efficacy and safety of SJZD in the prevention and treatment of CRAs recurrence.

Methods: SJZD on prevention and treatment of CRAs recurrence after resection: a multicenter, randomized, double-blind, placebo-controlled trial was designed. Patients who undergo polypectomy of CRAs will be recruited and randomized into a SJZD group and a placebo group in a 1:1 ratio. The intervention phase will be 12 months. The follow-up period will last 24 months. The primary outcome is the CRA recurrence rate after intervention. The secondary outcomes include the CRA recurrence rate at the second year post-polypectomy, the pathological type of adenoma and the alterations in SDS scores after intervention.

Discussion: Previous clinical practice has observed the sound effect of SJZD in the context of gastrointestinal diseases. A number of experiments have also validated the active components in SJZD. This trial aims to provide tangible evidence for the usage of SJZD, hoping to reduce the recurrence of CRAs.

New management of surveillance in patients with baseline serrated polyps: a large single-center retrospective cohort study in China

BACKGROUND

Serrate d polyps (SP) is associated with an increased risk of colorectal cancer. Patients with SP history tend to have SP recurrence. However, the risk factors for metachronous polyps (MP) in those patients are not well established.

METHODS

Data of colonoscopy were retrospectively reviewed from October 2012 to October 2021. The pathology database, electronic medical records and telephone follow-up data were also observed.

RESULTS

A total of 906 patients were studied including 278 patients with MPs and 628 patients without. The multiplicity of polyps (OR, 13.63; 95% CI, 8.80-21.75), older age (OR, 5.71; 95% CI, 1.87-20.63), abdominal obesity (OR, 2.46; 95% CI, 0.98-6.42), current smoker (OR, 2.93; 95% CI, 1.15-7.83) and sedentary lifestyle (OR, 1.41; 95% CI, 1.22-1.65) are significantly associated with the risk of MPs. Patients with baseline SP < 10 mm were more likely to develop higher or same risk-grade polyps (HSRGP) ( P  = 0.0014). Patients with non-clinically significant SPs whether coexisted with adenoma or not were more likely to develop HSRGPs when compared to others ( P  < 0.001).

CONCLUSION

Total number of polyps, older age, sedentary behavior, abdominal obesity and smoking status contributed to the risk of MPs at surveillance colonoscopy. Patients with grade 1 SPs might require closer surveillance. SPs coexisting with conventional adenoma did not increase the risk of MPs but may increase the risk of developing HSRGPs.

Identification and clinical validation of key genes as the potential biomarkers in colorectal adenoma

BACKGROUND

Colorectal cancer (CRC), ranking third in cancer prevalence and second in mortality worldwide, is mainly derived from colorectal adenoma (CRA). CRA is a common benign disease in the intestine with rapidly increasing incidence and malignant potential. Therefore, this study aimed to recognize significant biomarkers and original pathogenesis in CRA.

METHODS

Transcriptome data of GSE8671, GSE37364, and GSE15960 were downloaded from the Gene Expression Omnibus (GEO) datasets, and differentially expressed genes (DEGs) were screened. Functional pathways enrichment, protein-protein interaction (PPI) network, stem-correlation analysis, CIBERSORT, risk score and survival analyses were performed. RT-qPCR and immunohistochemical staining were applied to verify our results.  RESULTS: Screening for significant DEGs in each dataset, we identified 230 robust DEGs, including 127 upregulated and 103 downregulated genes. Functional pathways enrichment showed that these DEGs were distinctly enriched in various tumor-associated pathways, such as growth factor activity, extracellular structure organization, neutrophil activation, and inflammatory response. We filtered out two hub genes via STRING and Modules analysis, including CA2 and HSD11B2. Stem-correlation analysis displayed that hub genes were negatively associated with stem-related genes (Olfm4, CD44, CCND1 and MYC). The CIBERSORT algorithm indicated that Macrophage2, activated mast cells, and Neutrophils promoted CRA progression through inflammation. Survival analysis showed that CA2 and HSD11B2 were positively associated with survival outcomes in CRC.

CONCLUSION

Our study has successfully identified the critical role of two core genes in the development and oncogenesis of CRA, which provides novel insight into the underlying pathogenesis, potential biomarkers and therapeutic targets.

Chinese consensus on prevention of colorectal neoplasia (2021, Shanghai)

Most patients with colorectal cancer (CRC) were diagnosed in advanced stage and the prognosis is poor. Therefore, early detection and prevention of CRC are very important. As with other cancers, there is also the tertiary prevention for CRC. The primary prevention is etiological prevention, which is mainly the treatment of adenoma or inflammation for preventing the development into cancer. The secondary prevention is the early diagnosis and early treatment for avoiding progressing to advanced cancer. The tertiary prevention belongs to the broad category of prevention, mainly for advanced CRC, through surgical treatment and postoperative adjuvant chemotherapy, radiotherapy, targeted therapy, immunotherapy for preventing tumor recurrence or metastasis. This consensus is based on the recent domestic and international consensus guidelines and the latest progress of international researches in the past five years. This consensus opinion seminar was hosted by the Chinese Society of Gastroenterology and Cancer Collaboration Group of Chinese Society of Gastroenterology, and was organized by the Division of Gastroenterology and Hepatology & Shanghai Institute of Digestive Disease, Renji Hospital, School of Medicine, Shanghai Jiao Tong University. The consensus opinion contains 60 statement clauses, the standard and basis of the evidence-based medicine grade and voting grade of the statement strictly complied with the relevant international regulations and practice.

Establishment and Verification of Scoring System for Colorectal Adenoma Recurrence

Objective

The purpose of this study was to establish and verify a risk-scoring system for colorectal adenoma recurrence.

Methods

A total of 359 patients with colorectal adenoma who underwent polypectomy from October 2017 to December 2018 were included in this retrospective study. Information including taking traditional Chinese medicine, demographic characteristics, adenoma characteristics were collected. The patients will review the colonoscopy one year after surgery. The patients were divided into a modeling cohort (216 cases) and a model validation cohort (143 cases) according to the ratio of 6:4. Modeling and model verification were performed by logistic regression, ROC curve, nomogram (calibration chart) and other methods.

Results

After adjusting for confounding factors by logistic regression, it was found that taking Chinese medicine, the number, size, site, pathological type and morphology of adenoma were independent influencing factors for the recurrence of colorectal adenoma. The area under the ROC curve (AUC) in the model validation cohort of established risk scoring system was 0.771 (95% CI: 0.694–0.847), indicating that there was good consistency.

Conclusion

The established risk prediction model of colorectal adenoma recurrence and its risk scoring system performed well and had high predictive value.

Fecal Fusobacterium nucleatum as a predictor for metachronous colorectal adenoma after endoscopic polypectomy

BACKGROUND AND AIM

Fusobacterium nucleatum is increasingly being recognized as an important risk factor in colorectal cancer and colorectal adenoma. Endoscopic polypectomy is associated with a decreased incidence of colorectal cancer; however, patients still suffer from a risk of metachronous adenoma. Currently, there are few effective non-invasive factors that may predict metachronous colorectal adenoma. Here, we evaluated the performance of F. nucleatum in predicting metachronous adenoma.

METHODS

Fecal samples and clinical information of patients before endoscopic polypectomy were collected from 367 patients in a retrospective cohort, and 238 patients in a prospective cohort. The abundance of fecal F. nucleatum was measured via quantitative polymerase chain reaction. Surveillance colonoscopies were conducted between 1 and 3 years after polypectomy (average follow-up 27.07 months for the retrospective cohort & 22.57 months for the prospective cohort) to identify metachronous adenoma. Candidate predictive factors and cut-off value of F. nucleatum abundance were identified from the retrospective cohort and then validated in the prospective cohort.

RESULTS

A high abundance of fecal F. nucleatum was found to be an independent risk factor for metachronous adenomas (odds ratio, 6.38; P < 0.001) in the retrospective cohort and was validated in the prospective cohort with a specificity of 65.00%, and a sensitivity of 73.04%, and an overall performance with the area under the curve of 0.73.

CONCLUSION

Fecal abundance of F. nucleatum may be a reliable predictor for metachronous adenoma after endoscopic polypectomy.

Clear colonoscopy as a surveillance tool in the prediction and reduction of advanced neoplasms: a randomized controlled trial

BACKGROUND

Missed and incompletely resected lesions remain the main cause of the recurrence of advanced neoplasms (ANs) in post-polypectomy patients. This study aims to determine whether the recurrence of ANs can be predicted and reduced by the newly developed clear colonoscopy procedure.

METHODS

Between 2006 and 2010, a total of 1350 participants with colorectal neoplasm were equally randomized to clear colonoscopy surveillance (CCS) and routine colonoscopy surveillance (RCS) in our center. Clear colonoscopy was achieved through repeat colonoscopy. On surveillance colonoscopy at 3 (for high-risk patients) and 5 (for low-risk patients) years, the recurrence of ANs and the relationship between the frequency of repeat examinations required for a clear colonoscopy and the recurrence of ANs were analyzed.

RESULTS

Surveillance colonoscopy at 3 and 5 years showed that the incidence of ANs in patients belonging to the CCS group was 1.7%, which was lower than 4.7% in patients belonging to the RCS group (P = 0.012) for both high- and low-risk patients. Out of the 1126 patients who achieved clear colonoscopy on first repeat examination, only 5 ( 0.4%) were found to have ANs on surveillance examination, whereas 12 out of the 217 (5.4%) patients on second repeat examination and 5 out of the 29 (17.2%) patients on third repeat examination were found to have ANs (P < 0.001).

CONCLUSION

Surveillance based on clear colonoscopy decreased the incidence of ANs in post-polypectomy patients. The number of repeat examinations required for a clear colonoscopy is an important factor in the prediction of the recurrence of ANs.

Epidemiology characteristics of ethnic minority colorectal cancer in Yunnan in Southwestern China

BACKGROUND

Colorectal cancer (CRC) is one of the world's deadliest cancers, and its mortality rate has been on the rise in China. Yunnan is a region with a higher concentration of ethnic minorities. CRC affects many people from ethnic minority groups, which differ from Han in terms of their age and gender compositions.

METHODS

We collected samples from 1,016 cases of CRC patients along with their case files at Yunnan Provincial Cancer Hospital from the period between January 2013 and December 2018.

RESULTS

In total, 7.1% (n=72) of all lung cancer cases diagnosed from 2013 to 2018 in Yunnan Provincial Cancer Hospital occurred in patients 40 years old or younger, 44% (n=447) were 40 to 60 years old, and 48.9% (n=497) were 60 years old or above. The composition ratio of CRC patients in the different age groups differed significantly and enhanced significantly with age, with a statistical significance of P<0.05. A total of 33.6% (n=38) of 113 minority patients and 16.8% (n=152) of 903 Han patients reported a history of smoking, and 23.0% (n=26) of 113 minority patients and 14.6% (n=132) of Han patients had a history of drinking. Long-term smoking and drinking are significantly associated with the incidence of CRC, and this was more significant among ethnic minorities (P<0.05).

CONCLUSIONS

The high incidence of CRC in Yunnan is strongly related to patients' lifestyles, and diet should be a core focus of efforts to prevent and treat CRC. Early screening and regular check for common tumor markers can also help to reduce the incidence of CRC and provide a basis for improvements in CRC treatment and prognosis in Yunnan.

Berberine versus placebo for the prevention of recurrence of colorectal adenoma: a multicentre, double-blinded, randomised controlled study

BACKGROUND

Chemoprevention of colorectal adenoma and colorectal cancer remains an important public health goal. The present study aimed to investigate the clinical potential and safety of berberine for prevention of colorectal adenoma recurrence.

METHODS

This double-blind, randomised, placebo-controlled trial was done in seven hospital centres across six provinces in China. Individuals aged 18-75 years who had at least one but no more than six histologically confirmed colorectal adenomas that had undergone complete polypectomy within the 6 months before recruitment were recruited and randomly assigned (1:1) to receive berberine (0·3 g twice daily) or placebo tablets via block randomisation (block size of six). Participants were to undergo a first follow-up colonoscopy 1 year after enrolment, and if no colorectal adenomas were detected, a second follow-up colonoscopy at 2 years was planned. The study continued until the last enrolled participant reached the 2-year follow-up point. All participants, investigators, endoscopists, and pathologists were blinded to treatment assignment. The primary efficacy endpoint was the recurrence of adenomas at any follow-up colonoscopy. Analysis was based on modified intention-to-treat, with the full analysis set including all randomised participants who received at least one dose of study medication and who had available efficacy data. The study is registered with ClinicalTrials.gov, number NCT02226185; the trial has ended and this report represents the final analysis.

FINDINGS

Between Nov 14, 2014, and Dec 30, 2016, 553 participants were randomly assigned to the berberine group and 555 to the placebo group. The full analysis set consisted of 429 participants in the berberine group and 462 in the placebo group. 155 (36%) participants in the berberine group and 216 (47%) in the placebo group were found to have recurrent adenoma during follow-up (unadjusted relative risk ratio for recurrence 0·77, 95% CI 0·66-0·91; p=0·001). No colorectal cancers were detected during follow-up. The most common adverse event was constipation (six [1%] of 446 patients in the berberine group vs one [<0·5%] of 478 in the placebo group). No serious adverse events were reported.

INTERPRETATION

Berberine 0·3 g twice daily was safe and effective in reducing the risk of recurrence of colorectal adenoma and could be an option for chemoprevention after polypectomy.

FUNDING

National Natural Science Foundation of China.

Progress in primary prevention of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors in the digestive tract, with high incidence and mortality. Most of CRC cases are diagnosed at the late stage, and the treatment effect is therefore poor. Thus, the prevention of CRC is particularly important. There have been many studies on the prevention of CRC in recent years. This paper will summarize the latest research on the primary prevention of CRC.

High risk factors for recurrence after resection of colorectal polyps

AIM: To investigate the high risk factors for recurrence after resection of colorectal polyps.

METHODS: A retrospective analysis was performed of patients who underwent endoscopic resection of colorectal polyps more than twice from January 2012 to December 2015 at Shanghai Putuo District Central Hospital to identify the high risk factors for recurrence.

RESULTS: A total of 54 patients was included. Univariate analysis showed that male gender, old age, low intestinal cleaning degree, adenomatous polyps, polyps < 1 cm, APC electric cauterization combined with high frequency electrocoagulation, and multiple polyps were risk factors for postoperative recurrence of colorectal polyps. Multivariate analysis showed that only age was an independent risk factor for postoperative recurrence of colorectal polyps.

CONCLUSION: Age, gender, polyp number, polyp pathology, and intestinal cleanliness are risk factors for postoperative recurrence of colorectal polyps. Insufficient bowel preparation and smaller polyps will increase the rate of missed diagnosis and increase the risk of postoperative recurrence.

Latest progress in research of factors associated with recurrence after resection of colorectal polyps

Colorectal polyps are growths projecting into the mucosal surface of the colon lumen. Colorectal polyps, especially colorectal adenomas, are considered precancerous lesions of colorectal cancer. With the continuous development of endoscopic technology, endoscopic treatment of colon polyps has been used widely. However, the recurrence rate is high, and the risk of recurrence and malignant transformation still exists. Therefore, more and more attention has been paid to the recurrence related factors after the resection of colorectal polyps. This article will review the latest progress in the research of factors related to recurrence after resection of colorectal polyps.

Progress in research of colorectal intraepithelial neoplasia and adenoma

Colorectal cancer is a common malignant tumor in the digestive system, and the early diagnosis of colorectal cancer has been the focus of its prevention and control. Colorectal intraepithelial neoplasia and adenoma are considered to be the most important precancerous lesions of colorectal cancer. In recent years, with the development of biological medicine, genetics,

and other disciplines, many studies have explored the relationship between intraepithelial neoplasia and adenoma and colorectal cancer, and some new research progress has been achieved to provide some guidance for the future clinical screening, regular follow-up and chemical prevention. However, it remains to be studied how colorectal intraepithelial neoplasia and adenoma form and evolve to colorectal cancer.

Consensus on the Prevention, Screening, Early Diagnosis and Treatment of Colorectal Tumors in China: Chinese Society of Gastroenterology, October 14-15, 2011, Shanghai, China

BACKGROUND

Colorectal cancer (CRC) is steadily increasing in China. Colorectal adenoma (CRA) is the most important precancerous disease of CRC. Screening for colorectal tumors can aid early diagnosis. Advances in endoscopic mucosal resection and endoscopic submucosal dissection can aid the early treatment of colorectal tumors. Furthermore, because of high risk of recurrence after removal of adenomas under endoscopy, factors contributing to recurrence, the follow-up mode and the interval established, and the feasibility of application and the time of various chemical preventions should be concerned. However, a relevant consensus on the screening, early diagnosis and treatment, and prevention of colorectal tumors in China is lacking.

SUMMARY

The consensus recommendations include epidemiology, pathology, screening, early diagnosis, endoscopic treatment, monitoring and follow-up, and chemoprevention of colorectal tumors in China.

KEY MESSAGE

This is the first consensus on the prevention, screening, early diagnosis and treatment of CRA and CRC in China based on evidence in the literature and on local data.

PRACTICAL IMPLICATIONS

Through reviewing the literature, regional data and passing the consensus by an anonymous vote, gastroenterology experts from all over China launch the consensus recommendations in Shanghai. The incidence and mortality of CRC in China has increased, and the incidence or detection rate of CRA has increased rapidly. Screening for colorectal tumors should be performed at age 50-74 years. Preliminary screening should be undertaken to find persons at high risk, followed by colonoscopy. A screening cycle of 3 years is recommended for persistent interventions. Opportunistic screening is a mode suitable for the current healthcare system and national situation. Colonoscopy combined with pathological examination is the standard method for the diagnosis of colorectal tumors. CRA removal under endoscopy can prevent CRC to some extent, but CRA has an obvious recurrence trend. The follow-up interval after the removal or surgery of colorectal tumors should be different with lesions. Primary prevention of CRA includes improved diet with more fiber, supplements containing calcium and vitamin D, supplements containing folic acid for those with low hemoglobin levels, and cessation of tobacco smoking. Non-steroidal anti-inflammatory drugs and selective cyclooxygenase-2 inhibitors have been recognized to prevent recurrence after adenoma removal.

Associations between circulating 1,25(OH)₂D concentration and odds of metachronous colorectal adenoma

Cellular-level studies demonstrate that the availability of the secosteroid hormone 1α,25-dihydroxyvitamin D [1,25(OH)2D] to colon cells promotes anti-carcinogenic activities. Although epidemiological data are relatively sparse, suggestive inverse trends have been reported between circulating 1,25(OH)2D concentration and colorectal neoplasia. We therefore sought to evaluate the relationship between circulating 1,25(OH)2D concentrations and odds for metachronous colorectal adenomas among 1,151 participants from a randomized trial of ursodeoxycholic acid for colorectal adenoma prevention. No relationship between 1,25(OH)2D and overall odds for metachronous lesions was observed, with ORs (95% CIs) of 0.80 (0.60-1.07) and 0.81 (0.60-1.10) for participants in the second and third tertiles, respectively, compared with those in the lowest (p-trend = 0.17). However, a statistically significant inverse association was observed between circulating 1,25(OH)2D concentration and odds of proximal metachronous adenoma, with an OR (95% CI) of 0.71 (0.52-0.98) for individuals in the highest tertile of 1,25(OH)2D compared with those in the lowest (p-trend = 0.04). While there was no relationship overall between 1,25(OH)2D and metachronous distal lesions, there was a significantly reduced odds for women, but not men, in the highest 1,25(OH)2D tertile compared with the lowest (OR 0.53; 95% CI 0.27-1.03; p-trend = 0.05; p-interaction = 0.08). The observed differences in associations with proximal and distal adenomas could indicate that delivery and activity of vitamin D metabolites in different anatomic sites in the colorectum varies, particularly by gender. These results identify novel associations between 1,25(OH)2D and metachronous proximal and distal colorectal adenoma, and suggest that future studies are needed to ascertain potential mechanistic differences in 1,25(OH)2D action in the colorectum.

Expression of aquaporin 3 and 4 proteins in colorectal polyps

AIM: To investigate the expression of aquaporin 3 and 4 (AQP3, 4) proteins in colorectal polyps.

METHODS: One hundred and three patients with colorectal polyp and 10 healthy volunteers were selected, and 115 polyp tissue samples and 10 normal bowel mucosal tissue samples were collected from these subjects by colonoscopy. The protein expression of AQP3 and 4 was detected by immunohistochemistry.

RESULTS: The expression of AQP3 and 4 proteins was detected in colorectal epithelial cells that were located in the basolateral membrane. The protein expression of AQP3 and 4 in the inflammatory polyps group was significantly higher than that in the normal group (P < 0.01, P < 0.05). The protein expression of AQP3 was significantly lower in hyperplastic polyps and adenomas than in normal bowel mucosal tissue (both P < 0.01). There was a positive correlation between AQP3 and AQP4 expression in colorectal polyps and normal bowel mucosa (r = 0.61, P = 0.000).

CONCLUSION: AQP3 and 4 proteins are abnormally expressed in colorectal polyps and there is a positive correlation between AQP3 and AQP4 expression.

A follow-up study of 166 cases of advanced colorectal adenomas after polypectomy

AIM: To investigate the characteristics of recurrence of advanced colorectal adenomas after polypectomy.

METHODS: The clinical data for patients with advanced colorectal adenoma who underwent polypectomy from January 2004 to January 2009 were collected and reevaluated. The patients who had follow-up data were included in the study.

RESULTS: A total of 497 patients with diagnosed advanced colorectal adenoma were collected, and follow-up data were available in 166 patients. These patients ranged in age from 32 to 82 years (average, 61.64 ± 11.07 years), and 128 cases had an age of ≥ 55 years (128/166, 77.11%). Ninety-four (94/166, 56.63%) patients were males. The most common initial manifestations of advanced adenomas were hematochezia (71/166, 46.38%) and lobular changes (75/166, 54.82%). The interval between polypectomy and first reexamination was 1-28 months. There were 102 (102/166, 61.45%) recurrences in all. Advanced colorectal adenomas in the left hemicolon more likely recurred in the left hemicolon, while those in the right hemicolon more likely recurred in the right hemicolon. No pathological differences were found between recurrent adenomas and original ones (P > 0.05). The hazard curve of Cox model suggested that the risk of recurrence increased gradually from 6 months after polypectomy.

CONCLUSION: Advanced colorectal adenomas may recur after polypectomy. No pathological differences were found between recurrent adenomas and original ones. Colonoscopy should be performed 6 mo after polypectomy for detection of possible recurrence.