Detection rate and proximal shift tendency of adenomas and serrated polyps: a retrospective study of 62,560 colonoscopies

Purpose

The purpose of this study is to estimate the detection rates of adenomas and serrated polyps and to identify proximalization and associate risk factors in patients from Southern China.

Methods

Consecutive patients undergoing colonoscopy from 2004 to 2013 in Guangzhou were included. The proportions of proximal adenomas to advanced adenomas and serrated polyps were compared and potential predictors were evaluated.

Results

Colonoscopies (n?=?62,560) were performed, and 11,427 patients were diagnosed with polyps. Detection rates for adenomas, hyperplastic polyps, and serrated adenomas were 12.0, 2.5, and 0.2 patients per 100 colonoscopies. When comparing the 1st (2004–2008) to the 2nd period (2009–2013), adenoma and serrated polyp detection in proximal and distal colon both increased significantly (proximal colon [adenoma 3.9 vs. 6.1 patients/100 colonoscopies, P?<?0.001; serrated polyp 0.4 vs. 1.1 patients/100 colonoscopies, P?<?0.001]; distal colon [adenoma 6.6 vs. 7.2 patients/100 colonoscopies, P?=?0.003; serrated polyp 1.2 vs. 2.4 patients/100 colonoscopies, P?<?0.001]). Advanced adenoma detection increased over these two periods only in proximal colon (1st vs. 2nd period: 1.5 vs. 2.4 patients/100 colonoscopies, P?<?0.001), not the distal colon (P?=?0.114). Multivariate analyses showed that diagnostic period was an independent predictor for adenoma proximalization (OR?=?1.36, 95% CI 1.25–1.48, P?<?0.001), but not for advanced adenomas (P?=?0.117) or serrated polyps (P?=?0.928).

Conclusions

Adenomas and serrated polyps were increasingly detected throughout the colon, whereas advanced adenomas were only in proximal colon. A proximal shift tendency detected by colonoscopy was observed for adenomas, but not advanced adenomas or serrated polyps, in Southern China. The screening for proximal polyps should be emphasized and colonoscopy might be a preferred initial screening tool.

     

Usefulness of plasma epigenetic changes of five major genes involved in the pathogenesis of colorectal cancer

Purpose

The purpose of present study was to investigate the methylation status of the promoter region in five genes (mothers against decapentaplegic homolog 4, fragile histidine triad protein, death-associated protein kinase 1, adenomatous polyposis coli (APC), and E-cadherin), which are known to be involved in the pathogenesis of colorectal cancer (CRC) and its clinicopathological significance.

Methods

The study subjects were 60 CRC patients, 40 patients with adenomatous colorectal polyp and 60 healthy control individuals. We further enrolled a total of 16 patients (two patients with Crohn’s disease, two patients with ulcerative colitis, one patient with serrated adenoma, and 11 patients with colorectal cancer). The methylation states of the five genes were determined in peripheral blood plasma using methylation-specific polymerase chain reaction single-strand conformation polymorphism analysis.

Results

This study showed the most sensitive epigenetic markers, E-cadherin (60 %), followed by APC (57 %), for detecting CRC. E-cadherin and APC had similar specificities and amplified 84 and 86 %, respectively, of CRC patients compared to non-CRC patients. Additionally, APC was the only marker to be significantly increased (OR?=?6.67, 95 % CI?=?1.19–23.4, P?=?0.045) and the most sensitive (57 %) and specific (89 %) marker in stage I CRC. Though we have not examined the paired cancer tissues and plasma, there was relatively high concordant rate (60–80 %) in our limited number of colorectal cancer patients.

Conclusions

Five genes, promoter methylation, in plasma were statistically significant risk factors in CRC patients. In this study, E-cad and APC genes may be particularly useful epigenetic biomarkers in plasma for the detection of CRC. Additionally, APC may able to identify early potential CRC.     

An australian audit of vaccination status in children and adolescents with inflammatory bowel disease

Background

Pre-existing polyps, especially large polyps, are known to be the major source for colorectal cancer, but there is limited available information about factors that are associated with polyp size and polyp growth. We aim to determine factors associated with polyp size in different age groups.

Methods

Colonoscopy data were prospectively collected from 67 adult gastrointestinal practice sites in the United States between 2002 and 2007 using a computer-generated endoscopic report form. Data were transmitted to and stored in a central data repository, where all asymptomatic white (n = 78352) and black (n = 4289) patients who had a polyp finding on screening colonoscopy were identified. Univariate and multivariate analysis of age, gender, performance site, race, polyp location, number of polyps, and family history as risk factors associated with the size of the largest polyp detected at colonoscopy.

Results

In both genders, size of the largest polyp increased progressively with age in all age groups (P < .0001). In subjects ≥ 80 years the relative risk was 1.55 (95% CI, 1.35-1.79) compared to subjects in the youngest age group. With the exception of family history, all study variables were significantly associated with polyp size (P < .0001), with multiple polyps (≥ 2 versus 1) having the strongest risk: 3.41 (95% CI, 3.29-3.54).

Conclusions

In both genders there is a significant increase in polyp size detected during screening colonoscopy with increasing age. Important additional risk factors associated with increasing polyp size are gender, race, polyp location, and number of polyps, with polyp multiplicity being the strongest risk factor. Previous family history of bowel cancer was not a risk factor.     

Overexpression of Lgr5 correlates with resistance to 5-FU-based chemotherapy in colorectal cancer

Background

The leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) is an adult intestinal stem cell marker frequently detected in human colorectal cancers (CRCs). However, the value of Lgr5 level in CRC prognosis and treatment prediction has not been well characterized.

Methods

We examined Lgr5 expression in 384 formalin-fixed paraffin-embedded CRC specimens from 296 CRC patients, including 64 patients treated with 5-fluorouracil (5-FU)-based chemotherapy. The effects of Lgr5 on cell proliferation, survival, and drug resistance were examined in cultured CRC cells.

Results

Elevated expression of Lgr5 was observed in CRC tissues, and Lgr5 protein levels were significantly correlated with an advanced American Joint Committee on Cancer stage (P?<?0.001), T stage (P?<?0.001), N stage (P?<?0.001), and distant metastasis (P?<?0.001). High expression levels of Lgr5 were significantly associated with shorter disease-free survival (P?<?0.001) and shorter cancer-specific survival (P?=?0.007) in CRC patients. Among the chemotherapy-treated subgroups, patients with low Lgr5 level showed a better response rate (65 %) than patients with high Lgr5 level (37 %) towards 5-FU-based treatment (P?=?0.025). In cultured CRC cell lines, knocking down Lgr5 suppressed cell proliferation and colony formation ability, while it enhanced apoptosis and rendered cells more sensitive to chemotherapeutic agents. In contrast, overexpression of Lgr5 increased cell proliferation and enhanced chemoresistance.

Conclusion

These results suggest that elevated Lgr5 level is associated with CRC progression and treatment response and has the potential to serve as a therapeutic target in CRC patients.     

Multicenter study of endoscopic mucosal resection using 0.13 % hyaluronic acid solution of colorectal polyps less than 20 mm in size

Purpose

Endoscopic mucosal resection (EMR) of colorectal polyps should be curative and safe. This study aimed to determine the efficacy and safety of colorectal EMR using 0.13 % hyaluronic acid (HA) solution.

Methods

This was a single-armed multicenter prospective open trial conducted at 11 Japanese institutions. Lesion characteristics and various measures of clinical outcome, including en bloc resection, histopathologically complete resection, and postoperative bleeding were analyzed for 624 consecutive patients who underwent EMR of colorectal polyps at ≤20 mm in size from August 2010 to September 2011.

Results

En bloc and complete resection were achieved in 93.3 and 78.3 % of 624 lesions. The median EMR procedure time was 2.1?±?1.5 min. The rates of postoperative bleeding and perforation were 1.1 and 0 %. The rate of en bloc resection was higher for polyps at 5–10 mm than for polyps at 11–20 mm (95.1 vs. 85.1 %; P?<?0.001) and was higher for protruding polyps than for superficial polyps (94.5 vs. 87.1 %; P?<?0.05). The rate of en bloc resection was also higher for polyps in the left-side colon than for those in the right-side colon or rectum (96.7 vs. 91.6 vs. 90.8 %; P?<?0.05). Multivariate analysis showed that polyp at 11–20 mm in size and location not on the left-side colon was significantly independent risk factors for failure of en bloc resection.

Conclusion

EMR using 0.13 % HA of colorectal polyps less than 20 mm in size had high rates of en bloc and complete resection and few complications.     

High-Definition White-Light (HDWL) Colonoscopy and Higher Adenoma Detection Rate and the Potential for Paradoxical Over Surveillance

Background

Patients undergoing high-definition white-light colonoscopy by a high adenoma detector may have a lower risk of interval adenoma detection on follow-up colonoscopy and may require less frequent follow-up but may paradoxically be assigned to more frequent surveillance when more adenomas are detected.

Aims

To evaluate whether high-definition white-light colonoscopy (vs. standard-definition white-light colonoscopy) and endoscopist adenoma detection rate (ADR) at index colonoscopy are associated with increased likelihood of adenomas at follow-up.

Methods

Longitudinal follow-up of prior cross-section cohort study of patients who underwent colonoscopy at baseline with at least one detected adenoma was included. Associations of type of white-light at index colonoscopy and the ADR of the endoscopist at index colonoscopy (high vs. low adenoma detector) were evaluated with various adenoma and polyp detection endpoints. Eighteen endoscopists were classified as high and low adenoma detectors based on the median ADR of 0.255.

Results

There were no significant differences in subsequent interval adenoma or polyp detection endpoints with regard to whether baseline exam was performed with high-definition white-light or standard-definition white-light colonoscopy nor between high and low ADR after adjusting for multiple testing (P ≤ 0.0029 considered significant). Prior to multiple testing adjustment, there was a significantly lower detection rate of hyperplastic polyps in the left colon (24 vs. 35 %, OR: 0.56, P = 0.033) at follow-up colonoscopy when baseline exam was performed with high-definition white-light index colonoscopy.

Conclusions

The results of this study do not support adjusting colonoscopy surveillance guidelines based on type of colonoscopy performed or the endoscopist’s ADR.     

p42.3: A promising biomarker for the progression and prognosis of human colorectal cancer

Purpose

As a novel cell cycle-related gene, p42.3 has been shown to play a key role in the cell proliferation and tumorigenicity of gastric cancer. To date, the association between p42.3 and colorectal cancer (CRC) has not been reported. This study investigated the expression of p42.3 and its potential role in human colorectal cancers.

Methods

Real-time polymerase chain reaction and western blotting were used to evaluate p42.3 mRNA and protein expression in 14 pairs of fresh frozen CRC samples, matched with adjacent normal mucosa. The p42.3 protein was evaluated by immunohistochemistry using CRC tissue microarrays, which included 212 CRC specimens and corresponding normal colorectal mucosa. The expression profiles of p42.3 in CRC tissues were analyzed against clinicopathological factors and post-surgical survival status. The expression profiles of p42.3 were also investigated in six human colon carcinoma cell lines.

Results

p42.3 was demonstrated to be over-expressed in colorectal cancer tissues compared with normal mucosa in the 14 tissue pairs (P = 0.011) and was significantly higher in patients with poor tumor differentiation (P = 0.045); patients positive for p42.3 expression had a poorer prognosis than those not expressing this protein (P = 0.033). In a multivariate survival analysis, p42.3 expression was identified as an independent prognostic factor for CRC patients (P = 0.030).

Conclusions

The results indicated that p42.3 might play an important role in the progression of CRC, and it has a great value for assessing CRC patient prognosis after surgery.     

Differential diagnosis of colorectal polyps with respect to similar capabilities of white light colonoscopy and narrow-band imaging

Purpose

The responses of polyps to light essentially determine the diagnostic capability of an endoscopy system in differentiating adenomas from hyperplastic polyps. Compared with white light colonoscopy (WLC), narrow-band imaging (NBI) is expected to improve the diagnostic capability. The diagnostic capabilities of WLC and NBI are evaluated and compared based on the polyp responses.

Methods

The following WLC and NBI images were retrospectively reviewed and categorized: 195 images and polyps (89 WLC, 106 NBI) with the best visual quality were categorized in the best image group (BG), and 484 images of 242 polyps (both WLC and NBI) were categorized in the paired image group (PG). For each reflection of light used for WLC or NBI, the polyp responses were objectively expressed as reflection features. The reflection features were then used to establish a classification model for identifying adenomas. The diagnostic capability of reflection feature or classification model was measured by the area under the receiver operating characteristic curve (AUC).

Results

In both image groups, the diverse and heterogeneous features of the polyp responses enabled accurate identification of adenomas, regardless of the light source used for WLC and NBI. For differential diagnosis of adenomas and hyperplastic polyps, the WLC and NBI did not significantly differ in BG (AUC, 0.905 and 0.922, respectively; P?=?0.690) or in PG (AUC, 0.782 and 0. 769, respectively; P?=?0.755).

Conclusions

Using WLC and NBI as classification models is effective in differential diagnosis of colorectal polyps and exhibited similar capabilities.     

Associations Between Markers of Colorectal Cancer Stem Cells and Adenomas Among Ethnic Groups

Background and Purposes

Most colorectal tumors develop from adenomatous polyps, which are detected by colonoscopy. African Americans (AAs) have higher incidence of colorectal cancer (CRC) and greater mortality from this disease than Caucasian Americans (CAs). We investigated whether differences in predisposition to CRC and its surrogate (colonic adenomas) between these ethnic groups were related to numbers of cancer stem or stem-like cells (CSCs) in colonocytes.

Methods

We analyzed colonic effluent from 11 AA and 14 CA patients who underwent scheduled colonoscopy examinations at the John D. Dingell Veterans Affairs Medical Center. We determined proportions of cells that expressed the CSC markers CD44 and CD166 by flow cytometry.

Results

The proportion of colonocytes that were CD44⁺CD166^? in effluent from patients with adenomas was significantly greater than from patients without adenomas (P?=?0.01); the proportion of CD44⁺CD166⁺ colonocytes was also greater (P?=?0.07). Effluent from AAs with adenomas had 60?% more CD44⁺166^? colonocytes than from CAs with adenomas. Using cutoff values of 8?% for AAs and 3?% for CAs, the proportion of CD44⁺166^? colonocytes that had positive predictive value for detection of adenomas was 100?% for AAs and CAs, determined by receiver operator characteristic curve analysis.

Conclusion

The proportion of CD44⁺166^? colonocytes in colonic effluent can be used to identify patients with adenoma. AAs with adenomas have a higher proportion of CD44⁺166^? colonocytes than CA. The increased proportion of CSCs in colonic tissue from AA might be associated with the increased incidence of CRC in this population.     

Predictive value of vascular endothelial growth factor overexpression in early relapse of colorectal cancer patients after curative resection

Background

Preclinical and clinical studies have indicated that vascular endothelial growth factor (VEGF) is the predominant angiogenic factor. Recently, there was a consistent trend of poorer survival rates in colorectal cancer (CRC) patients of earlier relapse. The purpose of this study was to investigate novel predictors of early relapse in stage I–III CRC and further to determine their correlation with disease outcomes.

Materials and methods

We retrospectively analyzed clinicopathological features and VEGF expression by immunohistochemical staining in 100 stage I–III CRC patients undergoing curative resection to identify predictors of postoperative early relapse.

Results

Among 100 patients, 40 patients were classified into early relapse group, and 60 patients were categorized into non-early relapse group. A multivariate logistic regression analysis showed that vascular invasion (P?=?0.048), perineural invasion (P?=?0.042), VEGF overexpression (P?=?0.023), and high postoperative carcinoembryonic antigen (CEA) levels (P?=?0.004) were independent predictors of early relapse. Additionally, we found that with more predictors such as the combined incidence of vascular invasion, perineural invasion, VEGF overexpression, and postoperative CEA levels are involved, the incidence of early postoperative relapse increases. Moreover, VEGF overexpression predicted not only early postoperative relapse but also disease-free survival (P?<?0.001) and overall survival (P?=?0.002).

Conclusions

This study suggests that VEGF overexpression is an important predictor of early postoperative relapse in patients with stage I–III CRC and may help identify patients who would benefit from intensive follow-up and therapeutic programs.     

Should a Colonoscopy be Recommended for Healthy Individuals with Increased Carcinoembryonic Antigen Levels? A Case�CControl Study

Background and Aim

Despite the limitations of screening or early diagnosis of colorectal cancers (CRC), carcinoembryonic antigen (CEA) is frequently measured in practice and during health promotion programs. The aim of this study was to evaluate the role of colonoscopy in healthy individuals with elevated CEA levels.

Methods

From January 2003 to November 2008, 117,731 healthy persons underwent an opportunistic screening program in two health promotion centers; 1,497 subjects (1.3%) showed an elevated CEA level (>5 ng/ml). Among them, 174 patients were recruited to undergo a colonoscopy to determine if colorectal malignancies were present. A total of 372 age- and sex-matched persons were selected as controls from among the healthy subjects who had a normal level of CEA and had received surveillance colonoscopy. The primary outcome was the incidences of CRC in elevated CEA and normal CEA groups. The secondary outcome was the predictive factors of CRC in the elevated CEA group.

Results

The incidence of CRC was higher in the group with higher CEA-levels than in the group with normal CEA levels (4.6 vs. 1.3%; P = 0.031). In the CEA-elevated group, patients with CRCs were diagnosed at more advanced stages than were those in the CEA-normal group. The incidence of colorectal polyps was not different between the two groups. In the CEA-elevated group, anemia was an independent predictive factor of CRCs by multivariate analysis (P = 0.002).

Conclusion

Anemia itself is not a predictive factor of CRC in the entire population, but is an independent predictive factor of CRC in healthy individuals with an elevated level of CEA. Therefore, colonoscopy should be recommended for healthy subjects with an elevated level of CEA accompanied with anemia in the absence of other adenocarcinomas to evaluate the presence of colorectal malignancy.     

Endoclip-Assisted Resection of Large Pedunculated Colorectal Polyps: Technical Aspects and Outcome

Background

The most common complication of polypectomy is hemorrhage, and various techniques have been used to prevent this complication.

Aim

This study evaluates the outcomes of endoclip-assisted polypectomy in patients with large pedunculated colorectal polyps, in comparison with a historical control group of patients treated with endoloop-assisted polypectomy.

Methods

Between January and December 2007, 32 patients with 32 large pedunculated polyps (≥15 mm) were treated with endoclip-assisted polypectomy (group A). Between January and December 2006, 35 patients with 35 large pedunculated polyps were treated; 33 with endoloop-assisted polypectomy (control, group B) and two cases with endoclips and needle knife, which were included in group A for the analysis.

Results

The mean (± standard deviation [SD]) size of polyp head was 26.8 ± 8.1 mm (range 15–50) in group A and 22.3 ± 4.1 mm (range 15–30) in group B (P = 0.004). In group A, six polyps had a mean (±SD) head size of 40.8 ± 5.8 mm (range 35–50) and were resected with clips and needle knife. In group A, bleeding occurred in two cases (5.9%), which were associated with the presence of cancer at histology (P = 0.006) and were managed by applying new clips. No bleeding occurred in patients of group B and no perforation and post-polypectomy syndrome occurred in either group. There were three (8.8%) cancerized adenomas in group A and one (3%) in group B. Clip application was possible in all patients, while in two cases, loop placement was impossible.

Conclusions

In our experience, endoclip-assisted resection is a safe alternative to endoloop for the resection of large pedunculated colorectal polyps when endoloop placement is difficult or impossible.     

Transanal endoscopic microsurgery for giant polyps of the rectum

Background

The potential for malignancy in rectal polyps increases with the size of the polyp, and unexpected malignancy is reported in up to 39 % of large rectal adenomas. Transanal endoscopic microsurgery (TEM) offers the possibility of an en bloc full-thickness excision for lesions in the rectum. We present our results with TEM in the removal of giant polyps equal or greater than 4 cm in diameter.

Methods

In the period between 1998 and 2012, TEM was performed in 39 patients with rectal polyps measuring at least 4 cm in diameter. Transrectal ultrasound and/or magnetic resonance imaging of the rectum was used when cancer was suspected.

Results

The polyp was removed with en bloc full-thickness excision in 77 % (n = 30). The preoperative diagnosis was benign rectal adenoma in 89.7 % (n = 35). The median size of the polyps was 30 cm² (range 16–100 cm²). Postoperative complications included bleeding in 4 patients (10.3 %). Histological examination showed unexpected cancer in 4 patients (10.3 %). TEM was curative in 2 of these patients, and the other 2 underwent further surgery. Recurrences occurred in 10 patients (25.6 %) and consisted of 5 adenomas and 5 adenocarcinomas. In 5 patients, these recurrences were treated with endoscopic removal or re-TEM. The remaining 5 underwent total mesorectal excision and/or chemotherapy.

Conclusions

Full-thickness TEM provides a safe and efficient treatment for excision of giant polyps. In case of unexpected cancer, TEM can be curative. Local recurrence can be often treated with a second TEM procedure.     

A novel summary report of colonoscopy: timeline visualization providing meaningful colonoscopy video information

Purpose

The colonoscopy adenoma detection rate depends largely on physician experience and skill, and overlooked colorectal adenomas could develop into cancer. This study assessed a system that detects polyps and summarizes meaningful information from colonoscopy videos.

Methods

One hundred thirteen consecutive patients had colonoscopy videos prospectively recorded at the Seoul National University Hospital. Informative video frames were extracted using a MATLAB support vector machine (SVM) model and classified as bleeding, polypectomy, tool, residue, thin wrinkle, folded wrinkle, or common. Thin wrinkle, folded wrinkle, and common frames were reanalyzed using SVM for polyp detection. The SVM model was applied hierarchically for effective classification and optimization of the SVM.

Results

The mean classification accuracy according to type was over 93%; sensitivity was over 87%. The mean sensitivity for polyp detection was 82.1%, and the positive predicted value (PPV) was 39.3%. Polyps detected using the system were larger (6.3?±?6.4 vs. 4.9?±?2.5 mm; P?=?0.003) with a more pedunculated morphology (Yamada type III, 10.2 vs. 0%; P?<?0.001; Yamada type IV, 2.8 vs. 0%; P?<?0.001) than polyps missed by the system. There were no statistically significant differences in polyp distribution or histology between the groups. Informative frames and suspected polyps were presented on a timeline. This summary was evaluated using the system usability scale questionnaire; 89.3% of participants expressed positive opinions.

Conclusions

We developed and verified a system to extract meaningful information from colonoscopy videos. Although further improvement and validation of the system is needed, the proposed system is useful for physicians and patients.

     

Characteristics of Small Bowel Tumors Detected by Double Balloon Endoscopy

Background

A few reports suggest that the emergence of double balloon endoscopy (DBE) has likely changed the clinical picture of small bowel tumors (SBTs).

Aim

To further clarify the characteristics of SBTs detected by DBE.

Methods

A retrospective chart review was conducted in 227 patients who had undergone DBE.

Results

The SBT group contained more symptomatic patients than the non-SBT group (90% vs. 49%, P < 0.0005) with a significantly higher rate of gastrointestinal symptoms at presentation (72% vs. 33%, P < 0.005). Twenty patients (8.8%) were eventually diagnosed with SBT, and their indications for DBE were obscure gastrointestinal bleeding (n = 5), abdominal pain (n = 5), abdominal fullness (n = 5), vomiting (n = 2), and diarrhea (n = 1). Tumors were located in the jejunum in 14 patients (70%) and in the ileum in 6 (30%). A final histological diagnosis was assigned to all 20 patients: primary adenocarcinoma (n = 8, 40%), malignant lymphoma (n = 5, 25%), metastatic cancer (n = 4, 20%), gastrointestinal stromal tumor (n = 1, 5%), carcinoid tumor (n = 1, 5%) and inflammatory fibroid polyp (n = 1, 5%). Stenosis or ulceration were the most frequently observed endoscopic findings (n = 13, 65%). All primary adenocarcinomas and three of four (75%) metastatic cancers showed stenosis or ulceration. Three of five (60%) malignant lymphomas showed multiple lymphomatous polyps. All patients but one underwent surgical resection or chemotherapy or both.

Conclusion

DBE is a safe and useful procedure that enables a precise diagnosis of SBTs.     

Low-grade dietary-related inflammation and survival after colorectal cancer surgery

Purpose

Prolong inflammation is a central process observed in several chronic conditions and may be responsible for survival. There is an increasing evidence showing the role of diet in inflammation and habitual diet may be responsible for low-grade inflammation. The purpose of our study was to assess the effect of inflammatory properties of habitual diet measured by the Dietary Inflammatory Index (DII) on survival among surgical patients treated for colorectal cancer (CRC).

Methods

A follow-up study among 689 CRC patients (mean age 58 years, ±8.9; 56.7 % males) treated surgically was performed in Krakow, Poland. Habitual diet was assessed by a standardized semiquantitative food frequency questionnaire. Next, 23 dietary items were used to calculate DIIs. Vital records were verified to determine status of the participants.

Results

Study has shown linear association between DII and survival time among CRC patients with totally removed cancer treated by chemotherapy (b = ?0.13, p = 0.024). After adjustment for several important covariates, DII was associated with survival during up to 3 years after surgery, but only in patients without distant metastases (3-year HR_DII>?2.27 = 0.61, 95 % CI 0.38–0.99).

Conclusions

The results of the investigation have shown the usefulness of the DII as a potential predictor of survival among patients without distant metastases treated surgically for CRC.     

Clinical correlations of miR-21 expression in colorectal cancer patients and effects of its inhibition on DLD1 colon cancer cells

Purpose

MicroRNA-21 (miR-21) is one of the miRNAs that are frequently and highly overexpressed in tumor tissue of colorectal cancer (CRC) patients; however, only a little is known about its functional role in CRC.

Methods

We examined the expression level of miR-21 in 44 paired samples of tumoral and non-tumoral colon tissues diagnosed for CRC using TaqMan real-time PCR method. Furthermore, we used miR-21 inhibitor (anti-miR-21) to transient knockdown of miR-21 in DLD-1 colon cancer cells and examined the effects of miR-21 silencing on viability, apoptosis, chemosensitivity, cell cycle, and migration of DLD1 cells.

Results

The expression levels of miR-21 were significantly increased in CRC tumor tissue (P?<?0.0001). Significant differences in miR-21 levels were observed also between CRC tissues of patients with CRC in different clinical stages: I vs. II (P?=?0.033) and I vs. IV (P?=?0.021). Kaplan–Meier analysis proved that the miR-21 expression levels are correlated to shorter overall survival of CRC patients (P?=?0.0341). MiR-21 silencing in DLD1 cell line had no effect on the cell viability; however, when combined with chemotherapeutics (5-FU, L-OHP, and SN38), it contributed to the decrease of cell viability. Suppression of miR-21 decreased cell migration ability of DLD-1 cells by nearly 30?% (P?=?0.016).

Conclusion

We have confirmed the overexpression of miR-21 in CRC samples and its correlation with advanced disease and shorter overall survival. These findings could be described in part by the fact that CRC cells with increased expression of miR-21 have higher migration ability.     

Risk factors for delayed postpolypectomy bleeding: how to minimize your patients’ risk

Purpose

Secondary bleeding after colonoscopic polypectomy is a serious complication. Most studies show polyp size, location, and shape to be important risk factors but other factors may allow refinement of risk. The aim of this study is to look for other factors associated with delayed postpolypectomy bleeding.

Methods

This case-matched study compares patients who developed postpolypectomy bleeding with those who underwent uncomplicated polypectomy. Matching was performed for known risk factors: polyp size, location and shape, with a ratio of three controls to one subject.

Results

Postpolypectomy bleeding occurred in 19/494 patients with polyps >2.0 cm diameter (3.8 %) and 11/4161 patients with polyps <2.0 cm (0.3 %). There was a median interval of 3 days (range 0–9 days) from polypectomy to hemorrhage. Twenty-five patients were readmitted to this institution. Ten (40.0 %) were transfused and 19 (76.0 %) were re-colonoscoped, with 13 needing either cautery (n?=?7) or adrenaline injection (n?=?6). Ninety patients were selected as controls, matched for polyp size, location, and shape. Mean age at polypectomy was 69.9?±?9.2 years for patients and 64.9?±?12.2 for controls (p?=?0.042); 63.3 % subjects were male, compared to 47.8 % of controls (p?=?0.140). Univariate analysis showed that older age, piecemeal polypectomy, need for additional sedation, concurrent diverticulosis and intraprocedural bleeding were significantly associated with increased risk of delayed bleeding. The associations between delayed bleeding and additional sedation, concurrent diverticulosis and intraprocedural bleeding were confirmed by multivariate logistic regression analysis.

Conclusion

Difficult colonoscopy and intraprocedural bleeding identify patients with a particularly high risk of secondary postpolypectomy bleeding. Preventive measures should be considered in such cases.     

Prevalence of Colorectal Neoplasia Among Young African Americans and Hispanic Americans

Background

The disproportionately higher incidence of and mortality from colorectal cancer (CRC) among African Americans (AA) led the American College of Gastroenterology to recommend screening starting at age 45 in 2005.

Aim

The purpose of this study was to determine the prevalence of colorectal neoplasia among 40–49-year-old inner city AA and Hispanic Americans (HA).

Methods

We reviewed the medical records of 2,435 inner city AA and HA who underwent colonoscopy regardless of indication and compared the prevalence of colorectal neoplasia between AA and HA patients. We used logistic regression models to calculate odds ratios (OR) and 95 % confidence intervals (CI).

Results

There were 2,163 AAs and 272 HA. There were 57 % women in both groups. A total of 158 (7 %) AA and 9 (3 %) HA (P = 0.014) underwent the procedures for CRC screening. When compared to HAs, AAs had higher prevalence of any polyp (35 vs. 18 %, OR = 2.53; 95 % CI 1.82–3.52). Overall, AA had higher prevalence of colorectal neoplasia (adenoma and cancer) when compared to HAs (16 vs. 10 %; OR = 1.68; 95 % CI 1.10–2.56).

Conclusion

We observed a higher frequency of colorectal neoplasia among 40–49-year-old AAs as compared to HAs suggesting an increased susceptibility to CRC risk in this population.