Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms

Retrospective cohort study investigating association between precancerous gastric lesions and colorectal neoplasm risk

Background

Colorectal cancer (CRC) is considered the most prevalent synchronous malignancy in patients with gastric cancer. This large retrospective study aims to clarify correlations between gastric histopathology stages and risks of specific colorectal neoplasms, to optimize screening and reduce preventable CRC.

Methods

Clinical data of 36,708 patients undergoing gastroscopy and colonoscopy from 2005-2022 were retrospectively analyzed. Correlations between gastric and colorectal histopathology were assessed by multivariate analysis. Outcomes of interest included non-adenomatous polyps (NAP), conventional adenomas (CAs), serrated polyps (SPs), and CRC. Statistical analysis used R version 4.0.4.

Results

Older age (≥50 years) and Helicobacter pylori infection (HPI) were associated with increased risks of conventional adenomas (CAs), serrated polyps (SPs), non-adenomatous polyps (NAP), and colorectal cancer (CRC). Moderate to severe intestinal metaplasia specifically increased risks of NAP and CAs by 1.17-fold (95% CI 1.05-1.3) and 1.19-fold (95% CI 1.09-1.31), respectively. For CRC risk, low-grade intraepithelial neoplasia increased risk by 1.41-fold (95% CI 1.08-1.84), while high-grade intraepithelial neoplasia (OR 3.76, 95% CI 2.25-6.29) and gastric cancer (OR 4.81, 95% CI 3.25-7.09) showed strong associations. More advanced gastric pathology was correlated with progressively higher risks of CRC.

Conclusion

Precancerous gastric conditions are associated with increased colorectal neoplasm risk. Our findings can inform screening guidelines to target high-risk subgroups, advancing colorectal cancer prevention and reducing disease burden.

The Effectiveness of Screening Total Colonoscopy for Preoperative Patients with Gastric Cancer

BACKGROUND

Colorectal cancer (CRC) is the most common cancer that coincides with gastric cancer (GC). Although the usefulness of total colonoscopy (TCS) as a CRC screening tool has been reported in preoperative patients with GC, the long-term outcome of patients with synchronous CRC (SCRC) remains unclear. This study aims to clarify the significance of preoperative screening TCS for GC in terms of survival outcomes.

PATIENTS AND METHODS

We included 796 patients who underwent preoperative screening TCS for GC. The risk factors, clinicopathological features, and survival outcome of SCRC were examined. Furthermore, the cost-effectiveness was evaluated from the perspective of improving the rates of mortality caused by CRC.

RESULTS

SCRC was observed in 43 patients (5.4%). Endoscopic treatment for SCRC was performed on 30 patients. In total, 15 patients underwent surgical resection, including 2 patients requiring additional surgery after endoscopic treatment. Regarding pathological stages, 25 patients had stage 0, 12 patients had stage I, 5 patients had stage II, and 1 patient had stage IIIB disease. The cumulative mortality rates were as follows: GC-related deaths, 12.6%; deaths from cancers other than CRC, 1%; deaths from other causes, 5.5%. No deaths were attributed to SCRC. Comparing the patients who did not undergo TCS, an incremental cost-effectiveness ratio analysis suggested that a screening cost of 5.86 million yen was required to prevent one CRC death.

CONCLUSIONS

Curative treatment was possible in all patients with SCRC. No deaths were attributed to SCRC, suggesting that screening TCS for GC is effective.

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, I2 = 85.12%, P = 0.00), especially in patients with GC (OR =1.80, 95%CI = 1.49 to 2.18, I2 = 25.55%, P < 0.1). Moreover, other risk factors including age (OR = 1.08, 95%CI = 1.00 to 1.17, I2 = 90.13%, P = 0.00) and male sex (OR = 2.31, 95%CI = 1.26 to 4.22, I2 = 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, I2 = 0.00%, P = 0.92) and smoking (OR = 1.03, 95%CI = 1.01 to 1.05, I2 = 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.

Simultaneous colonic metastasis of advanced gastric cancer: a case report

BACKGROUND

Although distant metastasis in gastric cancer can be present at the time of the initial diagnosis, colonic metastasis is extremely rare. This report describes a case of simultaneous colonic metastasis of advanced gastric cancer.

CASE PRESENTATION

The patient was a 78-year-old woman with nausea and epigastric pain. Upper gastrointestinal endoscopy revealed an advanced invasive ulcerative tumor in the lesser curvature of the stomach extending from the anterior to the middle portion. Colonoscopy revealed a 4-mm polyp-like lesion in the mid-transverse colon; therefore, a polypectomy was performed. Both gastric and colonic tumors showed poorly differentiated adenocarcinoma with signet ring cell carcinoma. After providing informed consent, the patient underwent a total gastrectomy. Histologic examination showed similar morphologic features of both gastric and colonic tumors. Immunohistochemistry staining showed that these tumor cells were positive for cytokeratin (CK) 7 and negative for CK20.

CONCLUSIONS

This was an extremely rare case of simultaneous colonic metastasis of advanced gastric cancer. Because missed metastasis can result in a poorer prognosis, we propose a systemic search including colonoscopy for patients with advanced gastric cancer, especially cases involving poorly differentiated adenocarcinoma or signet ring cell carcinoma.

Comparison of 2 L Polyethylene Glycol Plus Ascorbic Acid and 4 L Polyethylene Glycol in Elderly Patients Aged 60-79: A Prospective Randomized Study

BACKGROUND

The bowel-cleansing efficacy and safety of 2 L polyethylene glycol (PEG) with ascorbic acid (2L PEG + Asc) has rarely been studied in the elderly population. In this randomized trial, we compared the bowel cleanliness, safety, and tolerability of 2L PEG + Asc with those of 4 L PEG in an elderly population aged 60-79.

METHODS

Study participants were randomized either to 2L PEG + Asc or 4L PEG. The primary endpoint was the success rate of bowel preparation, using the Boston Bowel Preparation Scale. Before colonoscopy, all participants were questioned about adverse events and tolerability regarding purgative ingestion.

RESULTS

A total of 347 individuals were enrolled (2L PEG + Asc, 174; 4L PEG, 173). Mean age in the 2L PEG + Asc and the 4L PEG was 69.3 ± 5.6 and 69.3 ± 5.0, respectively (P = 0.917). The rate for successful bowel cleansing was comparable between the 2L PEG + Asc (92%) and the 4L PEG (96%, P = 0.118). Total ingested liquid including purgative and water was lower in the 2L PEG + Asc group (2.9 L) than in the 4L PEG group (4.2 L, P < 0.001). The tolerability of purgative was superior in the 2L PEG + Asc (overall satisfaction, P < 0.001; willingness to reuse, P < 0.001). There were no serious adverse events during the trial.

CONCLUSIONS

The bowel-cleansing efficacy of 2L PEG + Asc was comparable to that of 4L PEG. Tolerability was superior in the 2L PEG + Asc group. For older people, 2L PEG + Asc is an efficacious and safe bowel cleanser. (Clinical trial registration number: KCT0004123).

Postgastrectomy gastric cancer patients are at high risk for colorectal neoplasia: a case control study

Background/Aims

Several studies have shown that colorectal neoplasms (CRN) including colorectal cancer (CRC) may be prevalent in patients with gastric cancer. However, in most of these studies, colonoscopy to investigate the prevalence of CRN was performed prior to surgery. We aimed to investigate whether CRN was more prevalent in postgastrectomy gastric cancer patients than in healthy individuals.

Methods

We reviewed the medical records of those patients within a cohort of gastric cancer patients with gastrectomy who underwent colonoscopy between 2016 and 2017. Controls age- and sex-matched with gastric cancer patients at a 2:1 ratio were identified among those who underwent colonoscopy at a health-promotion center. The frequencies of CRN, advanced CRN (ACRN), and CRC among patients with gastrectomy were compared with those in the control subjects. A total of 744 individuals (gastric cancer, 248; control, 496) were included.

Results

The rates of CRN and ACRN in the gastric cancer group were higher than those in the healthy individuals (CRN, 47.6% vs. 34.7%, P<0.001; ACRN, 16.9% vs. 10.9%, P=0.020). The rate of CRC was comparable between the 2 groups (2.0% vs. 0.6%, P=0.125). Multivariate analysis identified previous gastrectomy for gastric cancer and male sex as significant risk factors for (A)CRN.

Conclusions

CRN and ACRN were more prevalent in patients who underwent surgery for gastric cancer than in the control group. Regular surveillance colonoscopy at appropriate intervals is indicated after gastrectomy.

Comparison of bowel-cleansing efficacy of split-dose and same-day dose bowel preparation for afternoon colonoscopy in patients with gastrectomy: a prospective randomized study

BACKGROUND

A split dose (SPD) of purgative is the recommended bowel-preparation method for colonoscopy, although for colonoscopy scheduled for the afternoon, a same-day dose (SDD) of purgative is recommended. However, it has not been determined whether SPD or SDD is better in patients with gastrectomy who are at high risk of suboptimal bowel cleansing. We compared the bowel-cleansing efficacy of SPD and SDD regimens in patients with gastrectomy who underwent colonoscopy in the afternoon.

METHODS

This was a prospective, randomized, assessor-blinded study. For the SDD group, polyethylene glycol (PEG) was ingested on the day of colonoscopy starting at 7 AM. In the SPD group, 2 L PEG was ingested at 9 PM the day before colonoscopy, and the remaining 2 L from 10 AM on the day of colonoscopy. Colonoscopy was performed from 1:30 PM. Before colonoscopy, the participants completed questionnaires asking about bowel-movement kinetics, adverse events, tolerability, overall satisfaction, and willingness to reuse the protocol. The bowel-cleansing efficacy was assessed using the Boston Bowel Preparation Scale.

RESULTS

A total of 193 subjects were included (SDD, 95; SPD, 98). The rate of successful bowel cleansing was comparable between the two groups (SDD, 92.6% vs. SPD, 95.9%; P = 0.37). The incidence of adverse events (nausea, vomiting, bloating, abdominal pain, and dizziness/headache) was also comparable between the two groups. However, sleep disturbance was higher in the SPD group (SDD, 10.5% vs. SPD, 25.5%; P = 0.01). Tolerability did not differ between the SDD and SPD groups (satisfaction, P = 0.11; willingness to reuse, P = 0.29).

CONCLUSIONS

The bowel-cleansing efficacy, safety profile, and patient tolerability of SDD and SPD were comparable. Both SDD and SPD regimens are feasible bowel-preparation methods for patients with gastrectomy who undergo colonoscopy in the afternoon.

TRIAL REGISTRATION

Clinical trial registration number: KCT0002699.

Patients with Gastric Polyps need Colonoscopy Screening at Younger Age: A Large Prospective Cross-Sectional Study in China

Background To date, it is not clarified whether patients with gastric polyps without any alarming symptoms for colorectal neoplasia need colonoscopy screening. The objective of this study is to prospectively determine the association between gastric polyps and colorectal neoplasia.

Methods A multicenter prospective cross-sectional study was performed from July 2012 to December 2014. We compared patients with and without gastric polyps for prevalence of colorectal adenomas. The odds ratios (OR) were computed by logistic regression analysis after multivariable adjustments.

Results Totally 1546 patients were included, with 770 patients in the gastric polyp group and 776 in the age- and sex- matched control group. Patients with gastric polyps had greater odds of having any colorectal adenoma (adjusted OR=2.34, 95% confidence interval [CI]: 1.79 to 3.06, p<0.001) and advanced colorectal adenomas (adjusted OR=2.71, 95% CI: 1.74 to 4.23, p<0.001) than those without. The positive association between gastric polyps and colorectal adenomas remained significant in both women (OR=2.34, 95% CI: 1.66 to 3.29, p<0.001) and men (OR=1.87, 95% CI: 1.31 to 2.66, p=0.001). Patients over the age of 40 with gastric polyps had a higher prevalence of colorectal adenomas than those without (40-49yr: OR=1.81, 95% CI=1.02-3.21, p=0.04; 50-59yr: OR=1.88, 95% CI=1.26-2.81, p<0.001; 60-74yr: OR=2.62, 95% CI=1.73-3.98, p<0.001).

Conclusions The presence of gastric polyps is significantly associated with a higher prevalence of colorectal adenomas, especially advanced colorectal adenomas. Colonoscopy might be considered in patients with gastric polyps, of any gender, and over the age of 40.

Is Colonoscopic Screening Necessary for Patients Younger than 50 Years with Gastric Adenoma or Cancer?

Patients, aged ≥ 50 years, with gastric neoplasm are reported to be at increased risk for colorectal neoplasia (CRN), while data regarding the risk of CRN in young patients, aged < 50 years with gastric neoplasm are limited. We aimed to investigate the risk of CRN according to the presence of gastric neoplasm in patients, aged < 50 years, and conducted a cross-sectional study on 131,888 asymptomatic examinees who underwent both esophagogastroduodenoscopy (EGD) and colonoscopy as part of a health screening program between 2010 and 2014. The prevalence of overall CRN (8.6% vs. 13.2%, P = 0.251) and advanced colorectal neoplasia (ACRN) (0.0% vs. 1.3%, P = 0.345) did not significantly differ according to the presence of gastric neoplasm in subjects, aged < 50 years. However, among subjects aged ≥ 50 years, patients with gastric neoplasm had a significantly higher proportion of overall CRN (48.2% vs. 31.7%, P < 0.001) and ACRN (12.5% vs. 4.5%, P < 0.001) compared with those without gastric neoplasm. Particularly, gastric neoplasm was an independent risk factor for ACRN after controlling for confounding factors among subjects, aged ≥ 50 years. In conclusion, gastric neoplasm was a risk factor for CRN in patients, aged ≥ 50 years, but not in patients, aged < 50 years. Young patients, aged < 50 years with gastric neoplasm do not need to undergo colonoscopy, whereas patients, aged ≥ 50 years with gastric neoplasm, should be considered a higher priority for colonoscopy.

Effect of Previous Gastrectomy on the Performance of Postoperative Colonoscopy

Purpose

The purpose of this study was to determine the effect of a prior gastrectomy on the difficulty of subsequent colonoscopy, and to identify the surgical factors related to difficult colonoscopies.

Materials and Methods

Patients with a prior gastrectomy who had undergone a colonoscopy between 2011 and 2014 (n=482) were matched (1:6) to patients with no history of gastrectomy (n=2,892). Cecal insertion time, intubation failure, and bowel clearance score were compared between the gastrectomy and control groups, as was a newly generated comprehensive parameter for a difficult/incomplete colonoscopy (cecal intubation failure, cecal insertion time >12.9 minutes, or very poor bowel preparation scale). Surgical factors including surgical approach, extent of gastrectomy, extent of lymph node dissection, and reconstruction type, were analyzed to identify risk factors for colonoscopy performance.

Results

A history of gastrectomy was associated with prolonged cecal insertion time (8.7±6.4 vs. 9.7±6.5 minutes; P=0.002), an increased intubation failure rate (0.1% vs. 1.9%; P<0.001), and a poor bowel preparation rate (24.7 vs. 29.0; P=0.047). Age and total gastrectomy (vs. partial gastrectomy) were found to be independent risk factors for increased insertion time, which slowly increased throughout the postoperative duration (0.35 min/yr). Total gastrectomy was the only independent risk factor for the comprehensive parameter of difficult/incomplete colonoscopy.

Conclusions

History of gastrectomy is related to difficult/incomplete colonoscopy performance, especially in cases of total gastrectomy. In any case, it may be that a pre-operative colonoscopy is desirable in selected patients scheduled for gastrectomy; however, it should be performed by an expert endoscopist each time.

Prostate cancer patients may have an increased risk of coexisting advanced colorectal neoplasms

Background/aims

Patients being treated for prostate cancer (PCa) have an increased risk of developing colorectal cancer. However, whether PCa patients are inherently at a higher risk of colorectal neoplasms (CRNs) is unknown. We aimed to investigate the risk of CRNs in PCa patients.

Materials and methods

Patients who had been diagnosed with PCa at a tertiary medical center and had colonoscopy within 1 year of the PCa diagnosis were investigated. Patients were propensity-matched 1:2 by age and body mass index to asymptomatic control subjects who had undergone colonoscopy for routine health screening. CRN was defined as histological confirmation of an adenoma or adenocarcinoma component. Advanced CRN was defined as any of the following: 1) histological findings of high-grade dysplasia, 2) inclusion of villous features, 3) tumor ≥1 cm in size, or 4) presence of an adenocarcinoma. Risk factors for CRN and advanced CRN were evaluated by univariate and multivariate analysis.

Results

A total of 191 patients diagnosed with PCa had colonoscopies within 1 year of PCa diagnosis. Of these, 23 patients with a history of previous malignancy and seven with incomplete colonoscopies were excluded, leaving 161 patients in the PCa group. Although presence of PCa was not a significant risk factor for CRN by multivariate analysis, PCa was a significant risk factor for advanced CRN (odds ratio [OR] 3.300; 95% confidence interval [CI] 1.766–6.167; P<0.001). Other significant risk factors for advanced CRN were age (OR 1.050; 95% CI 1.003–1.009; P=0.036) and body mass index (OR 1.205; 95% CI 1.067–1.361; P=0.003), whereas aspirin use (OR 0.414; 95% CI 0.173–0.990; P=0.047) was a preventive factor.

Conclusion

The risk of advanced CRN may be significantly increased in patients with PCa. Patients with PCa should have a colonoscopy at the time of PCa diagnosis.

Diagnostic accuracy of 18F-FDG PET/CT for detecting synchronous advanced colorectal neoplasia in patients with gastric cancer

Preoperative screening for synchronous colorectal neoplasia (CRN) has been recommended in patients with gastric cancer because patients with gastric cancer are at increased risk for synchronous CRN. The aim of this study was to investigate the diagnostic accuracy of F-fluorodeoxyglucose (F-FDG) positron emission tomography/computed tomography (PET/CT) for detecting synchronous advanced CRN in patients with gastric cancer.A total of 256 patients who underwent colonoscopy and F-FDG PET/CT for preoperative staging were enrolled in this study. The diagnosis of focal colonic F-FDG uptake on F-FDG PET/CT image was made based on histopathologic results from the colonoscopic biopsy. The F-FDG PET/CT result was considered as true positive for advanced CRN when focal F-FDG uptake matched colorectal carcinoma or adenoma with high-grade dysplasia in the same location on colonoscopy.Synchronous advanced CRN was detected in 21 of the 256 patients (4.7%). Sensitivity, specificity, and accuracy of F-FDG PET/CT were 76.2%, 96.2%, and 94.5%. The size of CRN with a true positive result was significantly larger than that with a false negative result.F-FDG PET/CT demonstrated high diagnostic accuracy for detecting synchronous advanced CRN in patients with gastric cancer. Colonoscopy is recommended as the next diagnostic step for further evaluation of a positive F-FDG PET/CT result in patients with gastric cancer.

Clinicopathologic features of gastric cancer with synchronous and metachronous colorectal cancer in Korea: are microsatellite instability and p53 overexpression useful markers for predicting colorectal cancer in gastric cancer patients?

BACKGROUND

A large-scale study was performed to identify the risk factors for developing synchronous and metachronous colorectal cancer (CRC) in gastric cancer (GC) patients, including microsatellite instability (MSI) and p53 overexpression.

METHODS

A total of 1041 GC patients who underwent endoscopic resection or surgery and underwent colonoscopy simultaneously or during surveillance for GC were consecutively enrolled. Clinicopathologic characteristics, MSI, and p53 overexpression were compared between the GC patients with and those without synchronous and metachronous CRC.

RESULTS

Of the 1041 patients, CRCs were detected in 67 (6.4 %) patients with GC. Forty-six (4.4 %) had synchronous CRC and 21 (2.0 %) had metachronous CRC. Univariate analysis indicated that age ≥63 years (P < 0.001), male sex (P = 0.005), and p53 overexpression (P = 0.040) were significantly associated with a higher incidence of CRC. However, body mass index, smoking, tumor location, tumor multiplicity, tumor histology, TNM stage, and MSI were not significantly associated with the incidence of CRC. Age ≥63 years (OR: 5.881; 95 % CI: 3.083-11.221; P < 0.001) and male sex (OR: 2.933; 95 % CI: 1.307-6.584; P = 0.009) were risk factors for CRC in GC patients according to multivariate analysis.

CONCLUSIONS

GC patients who are male and/or ≥63 years old are recommended to receive colonoscopy to detect CRC. MSI and p53 overexpression were not useful molecular markers for predicting CRC in GC.

The value of preoperative screening colonoscopies in patients with biliary tract cancer

BACKGROUND

The purpose of this study was to evaluate the value of preoperative screening colonoscopies in patients with biliary tract cancer.

METHODS

A total of 544 patients with biliary tract cancer who underwent preoperative screening colonoscopies between January 2005 and December 2012 were retrospectively analyzed.

RESULTS

Synchronous colorectal neoplasia was detected in 199 patients (36.7 %), with adenocarcinomas detected in 21 (3.9 %) patients, carcinoids in two (0.4 %) patients, and adenomas in 176 (32.4 %) patients. Of those with adenomas, 32 patients were diagnosed with advanced adenomas, defined as adenomas with a maximum diameter of >1 cm, villous histology, or high-grade dysplasia because these characteristics implied the risk of malignant transformation. Fifty-five (10.1 %) of the patients with colorectal neoplasia required resection (11 surgical and 44 endoscopic resections). There were no major adverse events related to the resection. Univariate and multivariate analyses revealed that smoking status [ex-smoker + current smoker vs. non-smoker: odds ratio (OR) 2.32; 95 % confidence interval (CI) 1.30-4.21] and advanced age (≥70 vs. ≤69 years: OR 2.22; 95 % CI 1.24-3.91) were independent risk factors of having a colorectal neoplasia that required resection.

CONCLUSIONS

In patients with biliary tract cancer, preoperative screening colonoscopy was feasible and provided valuable clinical information. Synchronous colorectal neoplasia was detected in a substantial number of patients. Preoperative screening colonoscopies should be considered especially in high-risk patients such as smokers and elderly patients.

Simultaneous total laparoscopic curative resection for synchronous gastric, cecal and rectal cancer: Report of a case

INTRODUCTION

Gastric cancer (GC) and colorectal cancer (CRC) are often diagnosed simultaneously. Recent technological advances in surgical techniques and devices have enabled the use of laparoscopic approaches for GC and CRC. Laparoscopic resection is expected to increase the number of cases of synchronous gastrointestinal (GI) cancers that meet the indication for laparoscopic surgery, owing to early detection of GI cancers and extended indications for laparoscopic surgery.

PRESENTATION OF CASE

We herein report a successful simultaneous total laparoscopic curative resection for synchronous early GC, early cecal cancer and advanced rectal cancer. The total time of the operation was 600min, and the estimated blood loss was 250ml. The patient was discharged on postoperative day (POD) 10 without postoperative complications.

CONCLUSION

Simultaneous total laparoscopic surgery is a minimally invasive, feasible treatment option for synchronous GI cancers.

Clinical significance of colonoscopy in patients with upper gastrointestinal polyps and neoplasms: a meta-analysis

BACKGROUND

Some authors have studied the relationship between the presence of polyps, adenomas and cancers of upper gastrointestinal tract (stomach and duodenum) and risk of colorectal polyps and neoplasms; however, the results are controversial, which may be due to study sample size, populations, design, clinical features, and so on. No meta-analysis, which can be generalized to a larger population and could provide a quantitative pooled risk estimate of the relationship, of this issue existed so far.

METHODS

We performed a meta-analysis to evaluate risk of colorectal polyps or neoplasms in patients with polyps, adenomas or cancers in upper gastrointestinal tract comparing with controls. A search was conducted through PubMed, EMBASE, reference lists of potentially relevant papers, and practice guidelines up to 27 November 2013 without languages restriction. Odd ratios (ORs) were pooled using random-effects models.

RESULTS

The search yielded 3 prospective and 21 retrospective case-control studies (n = 37152 participants). The principal findings included: (1) OR for colorectal polyps was 1.15 (95% CI, 1.04-1.26) in the gastric polyps group comparing with control groups; (2) Patients with gastric polyps and neoplasms have higher risk (OR, 1.31 [95% CI, 1.06-1.62], and 1.72 [95% CI, 1.42-2.09], respectively) of colorectal neoplasms comparing with their controls; and (3) Positive association was found between the presence of colorectal neoplasms and sporadic duodenal neoplasms (OR, 2.59; 95% CI, 1.64-4.11).

CONCLUSIONS

Findings from present meta-analysis of 24 case-control studies suggest that the prevalence of colorectal polyps was higher in patients with gastric polyps than in those without gastric polyps, and the risk of colorectal neoplasms increases significantly in patients with gastric polyps, neoplasms, and duodenal neoplasms. Therefore, screening colonoscopy should be considered for patients with upper gastrointestinal polyps and neoplasms.