Factors Associated With Recurrence of Advanced Colorectal Adenoma After Endoscopic Resection

Risk of advanced neoplasia after removal of colorectal adenomas with high-grade dysplasia

BACKGROUND

Many studies reported the presence of adenomas with high-grade dysplasia (HGD) at index colonoscopy increased the incidence of advanced neoplasia (AN) and colorectal cancer (CRC) following. However, the conclusion remains obscure due to lack of studies on the specific population of adenomas with HGD. This study aimed to assess the long-term risk of AN and CRC after removal of adenomas with HGD.

METHODS

A total of 814 patients who underwent adenomas with HGD removal between 2010 and 2019 were retrospectively analyzed. The outcomes were the incidences of AN and CRC during surveillance colonoscopy. Cox proportional hazards models were utilized to identify risk factors associated with AN and CRC.

RESULTS

During more than 2000 person-years of follow-up, we found that AN and CRC incidence densities were 44.3 and 4.4 per 1000 person-years, respectively. The 10-year cumulative incidence of AN and CRC were 39.1% and 5.5%, respectively. In the multivariate model, synchronous low-risk polyps (HR 1.80, 95% CI 1.10-2.93) and synchronous high-risk polyps (HR 3.99, 95% CI 2.37-6.72) were risk factors for AN, whereas participation in surveillance colonoscopy visits (HR 0.56, 95% CI 0.36-0.88 for 1 visit; HR 0.10, 95% CI 0.06-0.19 for ≥ 2 visits) were associated with decreased AN incidence. Additionally, elevated baseline carcinoembryonic antigen (CEA) level (HR 10.19, 95% CI 1.77-58.59) was a risk factor for CRC, while participation in ≥ 2 surveillance colonoscopy visits (HR 0.11, 95% CI 0.02-0.56) were associated with decreased CRC incidence. Interestingly, for 11 patients who developed CRC after removal of adenomas with HGD, immunohistochemistry revealed that 8 cases (73%) were deficient mismatch repair CRCs.

CONCLUSIONS

Patients who have undergone adenoma with HGD removal are at higher risk of developing AN and CRC, while surveillance colonoscopy can reduce the risk. Patients with synchronous polyps, or with elevated baseline CEA level are considered high-risk populations and require more frequent surveillance.

New Model to Predict Recurrence After Endoscopic Mucosal Resection of Non-pedunculated Colonic Polyps ≥ 20 mm

BACKGROUND

Polyp recurrence is common after endoscopic mucosal resection (EMR) of non-pedunculated colonic polyps ≥ 20 mm. Two models haven been published for polyp recurrence prediction: Sydney EMR recurrence tool (SERT) and the size, morphology, colonic site, and access to target (SMSA) score. None of these models have been evaluated in a real-world United States (U.S.) cohort. We aimed to evaluate the external validity of these two models and develop a new model.

METHODS

Retrospective cohort study of patients with non-pedunculated polyps ≥ 20 mm that underwent EMR between 1/1/2012 and 6/30/2020. Univariate and multivariate analysis were performed to identify predictors of polyp recurrence to build a new model. Receiver Operating Characteristic (ROC) curves for the new model, SERT and a modified version of SMSA were derived and compared.

RESULTS

A total of 461 polyps from 461 unique patients were included for analysis. The average polyp size was 29.1 ± 12.4 mm. Recurrence rate at first or second surveillance colonoscopy was 29.0% at a 15.6 months median follow up (IQR 12.3-17.4). A model was created with 4 variables from index colonoscopy: size > 40 mm, tubulovillous adenoma histology, right colon location and piecemeal resection. ROC curves showed that the Area Under the ROC (AUC) for the new model was 0.618, for SERT 0.538 and for mSMSA 0.550.

CONCLUSION

SERT score and mSMSA have poor external validity to predict polyp recurrence after EMR of non-pedunculated polyps > 20 mm. Our new model is simpler and performs better in this multiethnic, non-referral cohort from the U.S.

Treatment of adenoma recurrence after endoscopic mucosal resection

OBJECTIVE

Residual or recurrent adenoma (RRA) after endoscopic mucosal resection (EMR) of large non-pedunculated colorectal polyps (LNPCPs) of ≥20 mm is a major limitation. Data on outcomes of the endoscopic treatment of recurrence are scarce, and no evidence-based standard exists. We investigated the efficacy of endoscopic retreatment over time in a large prospective cohort.

DESIGN

Over 139 months, detailed morphological and histological data on consecutive RRA detected after EMR for single LNPCPs at one tertiary endoscopy centre were prospectively recorded during structured surveillance colonoscopy. Endoscopic retreatment was performed on cases with evidence of RRA and was performed predominantly using hot snare resection, cold avulsion forceps with adjuvant snare tip soft coagulation or a combination of the two.

RESULTS

213 (14.6%) patients had RRA (168 (78.9%) at first surveillance and 45 (21.1%) thereafter). RRA was commonly 2.5-5.0 mm (48.0%) and unifocal (78.7%). Of 202 (94.8%) cases which had macroscopic evidence of RRA, 194 (96.0%) underwent successful endoscopic therapy and 161 (83.4%) had a subsequent follow-up colonoscopy. Of the latter, endoscopic therapy of recurrence was successful in 149 (92.5%) of 161 in the per-protocol analysis, and 149 (73.8%) of 202 in the intention-to-treat analysis, with a mean of 1.15 (SD 0.36) retreatment sessions. No adverse events were directly attributable to endoscopic therapy. Further RRA after endoscopic therapy was endoscopically treatable in most cases. Overall, only 9 (4.2%, 95% CI 2.2% to 7.8%) of 213 patients with RRA required surgery.Thus 159 (98.8%, 95% CI 95.1% to 99.8%) of 161 cases with initially successful endoscopic treatment of RRA and follow-up remained surgery-free for a median of 13 months (IQR 25.0) of follow-up.

CONCLUSIONS

RRA after EMR of LNPCPs can be effectively treated using simple endoscopic techniques with long-term adenoma remission of >90%; only 16% required retreatment. Therefore, more technically complex, morbid and resource-intensive endoscopic or surgical techniques are required only in selected cases.

TRIAL REGISTRATION NUMBERS

NCT01368289 and NCT02000141.

The impact of abdominal compression devices on colonoscopy outcomes: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Colonoscopy is the gold standard method for colorectal cancer screening. Looping occurs in 91% of cases undergoing colonoscopy and can cause patient discomfort, prolonged cecal intubation time (CIT), and colon perforation. This meta-analysis investigates the impact of abdominal compression devices (ACD) on colonoscopy outcomes.

METHODS

A systematic review and meta-analysis synthesizing randomized controlled trials (RCTs), retrieved by systematically searching: PubMed, EMBASE, WOS, SCOPUS, and Cochrane through February 2nd, 2023. Continuous and dichotomous outcomes were pooled using mean difference (MD) and risk ratio (RR) along with confidence interval (CI) using Revman. Our review protocol was prospectively published on PROSPERO with ID: CRD42023397344.

RESULTS

We included eight RCTs with a total of 1,889 patients. ACD was effective to decrease CIT (MD: -2.15 with a 95% CI [-3.49, -0.80], p = .002), postural change (RR: 0.57 with 95% CI [0.49, 0.66], p = .00001), and VAS pain score (MD: -1.49 with 95% CI [-1.81, -1.17], p = .0001). However, there was no difference between ACD and control groups regarding manual compression (RR: 0.65 with 95% CI [0.42, 1.00], p = .05), complete colonoscopy rate (CCR) (RR: 1.01 with 95% CI [0.99, 1.04], p = .31), and cecal intubation length (CIL) (MD: -2.25 with 95% CI [-7.64, 3.14], p = .41).

CONCLUSION

ACD during colonoscopy may enhance patient comfort by reducing CIT, pain, and postural changes. Nevertheless, additional RCTs are necessary to validate these results and determine the most suitable approach to utilize ACD for colonoscopy.

Young adults with colon cancer: clinical features and surgical outcomes

BACKGROUND

The clinicopathological features, surgical outcomes, and long-term survival of patients with young-onset colon cancer (≤ 40 years old) remain controversial.

METHODS

The clinicopathologic and follow-up data of patients aged < 40 years with colon cancer between January 2014 and January 2022 were reviewed. The primary objectives were clinical features and surgical outcomes. Long-term survival was investigated as a secondary objective.

RESULTS

Seventy patients were included in the study, and no significant rising trend (Z=0, P=1) of these patients was observed over the 8-year study period. Stage IV disease was accompanied by more ulcerative or infiltrating type (84.2% vs. 52.9%, P=0.017) and lymphovascular or perineural invasion (64.7% vs. 25.5%, P=0.003) than stage I-III disease. After a median follow-up time of 41 months (range 8-99 months), the 1-, 3-, and 5-year estimated overall survival (OS) rates were 92.6%, 79.5%, and 76.4%, respectively. The 1-, 3-, and 5-year progression-free survival (PFS) rates were 79.6%, 71.7%, and 71.7%, respectively. Multivariate Cox regression showed that M+ stage (hazard ratio [HR], 3.942; 95% confidence interval [CI], 1.176-13.220, P=0.026) was the only independent risk factor affecting OS. Meanwhile, tumor deposits (HR, 4.807; 95% CI, 1.942-15.488, P=0.009), poor differentiation (HR, 2.925; 95% CI, 1.012-8.454, P=0.047), and M+ stage (HR, 3.540; 95% CI, 1.118-11.202, P=0.032) independently affected PFS.

CONCLUSIONS

The differences in the clinical features, surgical outcomes, and long-term survival between young adults and elderly colon cancer patients need further investigation.

Combination of neutrophil/lymphocyte ratio and albumin/bilirubin grade as a prognostic predictor for hepatocellular carcinoma patients undergoing curative hepatectomy

BACKGROUND AND AIM

Prognosis determination is essential for hepatocellular carcinoma (HCC) patient management and treatment planning. The current study aimed to evaluate the prognosis performance of NLR, ALBI, and the combination of NLR-ALBI in determining the overall survival (OS) of HCC patients under curative hepatectomy.

METHODS

144 primary HCC patients with curative hepatectomy were recruited in the retrospective study. The clinicopathologic characteristics and OS were compared between stratified groups. The predictive performance of NLR, ALBI, and the combination of NLR-ALBI was explored by the area under the receiver operating characteristic curve (AUC). Univariate and multivariate analyses were used to determine the risk factors of OS.

RESULTS

AUC determined NLR cutoff > 2.60 for predicting prognosis. The univariate analysis indicated pathological differentiation, tumor size, AFP, TNM stage, NLR score, and ALBI grade were significant indicators of OS. However, only TMN grade, AFP, NLR score, and NLR-ALBI score were identified as independent predictors of OS in the multivariable analysis. The AUC of NLR, ALBI and the combination of NLR-ALBI was 0.618(95%CI 0.56-0.710), 0.533 (95%CI 0.437-0.629), 0.679 (95%CI 0.592-0.767) respectively. Patients with higher NLR-ALBI scores presented worse outcomes than those with lower NLR-ALBI scores.

CONCLUSION

NLR is an independent prognostic factor of HCC and a reliable biomarker in predicting the OS of HCC patients. The combination of NLR-ALBI showed a better prognostic performance than using NLR or ALBI alone, implicating the effectiveness and feasibility of combining multiple risk factors for postoperative prognosis assessment.

Postoperative serum interleukin-6 levels correlate with survival in stage I-III colorectal cancer

AIMS

The preoperative serum levels of inflammatory mediators, including C-reactive protein (CRP), procalcitonin (PCT) and interleukin-6 (IL-6), have been demonstrated to be correlated with patient outcomes in colorectal cancer (CRC); however, the prognostic role of these levels has been less well-studied in postoperative settings.

MATERIALS AND METHODS

A total of 122 stage I-III CRC patients were retrospectively enrolled. Serum levels of CRP, PCT and IL-6 were measured after surgery, and their prognostic value was evaluated. Kaplan-Meier analysis was used to determine the differences in disease-free survival (DFS) and overall survival (OS) between patients with different levels of these mediators, and the Cox proportional hazards model was used to estimate the risk factors.

RESULTS

In contrast to CRP and PCT, only the level of IL-6 was significant in predicting DFS (P = 0.01) but not OS (P = 0.07). A total of 66.39% (81/122) of patients were assigned to the low IL-6 group and no significant differences were found in the collected clinicopathological parameters among the low or high IL-6 subgroups. The level of IL-6 was negatively correlated with postoperative (1 w) (R=-0.24, P = 0.02) absolute lymphocyte counts. Patients with low levels of IL-6 had better DFS (log rank = 6.10, P = 0.01) but not OS (log rank = 2.28, P = 0.13). Finally, the level of IL-6 was an independent risk factor for DFS (HR: 1.81, 95% CI: 1.03-3.15, P = 0.04).

CONCLUSIONS

Compared to CRP and PCT, the level of IL-6 was observed to be the only significant factor in predicting the prognosis of stage I-III CRC patients after surgery, and a low level of IL-6 was associated with good DFS.

Evolution of endoscopic mucosal resection (EMR) technique and the reduced recurrence of large colonic polyps from 2012 to 2020

BACKGROUND

Endoscopic mucosal resection (EMR) is an effective method for removing non-pedunculated polyps ≥ 20 mm. We aimed to examine changes in EMR techniques over a 9-year period and evaluate frequency of histologic-confirmed recurrence.

METHODS

We identified patients who underwent EMR of non-pedunculated polyps ≥ 20 mm at a safety net and the Veteran's Affairs (VA) hospital in Houston, Texas between 2012 and 2020. Odds ratios (ORs) and 95% confidence intervals (CI) for associations with recurrence risk were estimated using multivariable logistic regression.

RESULTS

461 unique patients were included. The histologic-confirmed recurrence was 29.0% at 15.6 months median follow up (IQR 12.3 - 17.4). Polyps removed between 2018 and 2020 had a 0.43 decreased odds of recurrence vs. polyps removed between 2012 and 2014. The use of viscous lifting agents increased over time (from 0 to 54%), and the use of saline was associated with increased risk of recurrence (OR 2.28 [CI 1.33 - 3.31]).

CONCLUSIONS

Histologic-confirmed recurrence after EMR for non-pedunculated polyps ≥ 20 mm decreased over the seven year-period. Saline was associated with a higher risk of recurrence and the use of more viscous agents increased over time.

Implication of Obesity and Gut Microbiome Dysbiosis in the Etiology of Colorectal Cancer

The complexity and variety of gut microbiomes within and among individuals have been extensively studied in recent years in connection to human health and diseases. Our growing understanding of the bidirectional communication between metabolic diseases and the gut microbiome has also highlighted the significance of gut microbiome dysbiosis in the genesis and development of obesity-related cancers. Therefore, it is crucial to comprehend the possible role of the gut microbiota in the crosstalk between obesity and colorectal cancer (CRC). Through the induction of gut microbial dysbiosis, gut epithelial barrier impairment, metabolomic dysregulation, chronic inflammation, or dysregulation in energy harvesting, obesity may promote the development of colorectal tumors. It is well known that strategies for cancer prevention and treatment are most effective when combined with a healthy diet, physical activity, and active lifestyle choices. Recent studies also suggest that an improved understanding of the complex linkages between the gut microbiome and various cancers as well as metabolic diseases can potentially improve cancer treatments and overall outcomes. In this context, we herein review and summarize the clinical and experimental evidence supporting the functional role of the gut microbiome in the pathogenesis and progression of CRC concerning obesity and its metabolic correlates, which may pave the way for the development of novel prognostic tools for CRC prevention. Therapeutic approaches for restoring the microbiome homeostasis in conjunction with cancer treatments are also discussed herein.

Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

Do Biliary Stents Affect EUS-Guided Tissue Acquisition (EUS-TA) in Solid Pancreatic Lesions Determining Biliary Obstruction? A Literature Review with Meta-Analysis

There is a paucity of evidence regarding whether biliary stents influence endoscopic ultrasound-guided tissue acquisition using either fine-needle biopsy (EUS-FNB) or fine-needle aspiration (EUS-FNA), among patients with head of pancreas (HOP) lesions. We aimed at assessing the diagnostic accuracy of endoscopic ultrasound-guided tissue sampling in patients with or without bile duct stents. A total of seven studies with 2458 patients were included. The main aim was to assess overall pooled diagnostic accuracy. A pairwise meta-analysis was performed using a random effects model. Outcomes were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). We found that pooled accuracy was 85.4% (CI 78.8-91.9) and 88.1% (CI 83.3-92.9) in patients with and without stents, respectively. There was no statistically significant difference between the two (OR 0.74; p = 0.07). Furthermore, patients with metal stents demonstrated a significant difference (OR 0.54, 0.17-0.97; p = 0.05), which was not seen with plastic stents. EUS-FNB showed poorer diagnostic accuracy with concurrent biliary stenting (OR 0.64, 0.43-0.95; p = 0.03); however, the same was not observed with EUS-FNA. Compared to plastic stents, metal biliary stenting further impacted the diagnostic accuracy of EUS-guided tissue acquisition for pancreatic head lesions. There was no difference in the rate of procedure-related adverse events between the stent and no-stent groups.

Loss of Peroxiredoxin IV Protects Mice from Azoxymethane/Dextran Sulfate Sodium-Induced Colorectal Cancer Development

Peroxiredoxin IV (Prx4), a typical two-cysteine-containing member of the peroxidase family, functions as an antioxidant to maintain cellular redox homeostasis through the reduction of reactive oxygen species (ROS) via cycles of oxidation-reduction reactions. Under oxidative stress, all Prxs including Prx4 are inactivated as their catalytic cysteines undergo hyperoxidation, and hyperoxidized two-cysteine Prxs can be exclusively repaired and revitalized through the reduction cycle catalyzed by sulfiredoxin (Srx). Previously, we showed that Prx4 is a preferred substrate of Srx, and knockout of Srx in mice leads to resistance to azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis. To further understand the significance of the Srx/Prx4 axis in colorectal cancer development, Prx4-/- mice were established and subjected to standard AOM/DSS protocol. Compared with wildtype littermates, mice with Prx4-/- genotype had significantly fewer and smaller tumors. Histopathological analysis revealed that loss of Prx4 leads to increased cell death through lipid peroxidation and lower infiltration of inflammatory cells in the knockout tumors compared to wildtype. Treatment with DSS alone also showed decreased infiltration of macrophages and lymphocytes in the colon of knockout mice, suggesting a role for Prx4 in inflammatory response. In addition, loss of Prx4 caused alterations in plasma cytokines and chemokines after DSS and AOM/DSS treatments. These findings suggest that loss of Prx4 protects mice from AOM/DSS-induced colon tumorigenesis. Thus, targeting Prx4 may provide novel strategies for colon cancer prevention and treatment.

New Perspectives on Endoscopic Management of Liver and Pancreatic Cancer

Liver and pancreatic cancers are major health issues which represent a clinical and economic burden worldwide [...].

Endoscopic Ultrasound Advanced Techniques for Diagnosis of Gastrointestinal Stromal Tumours

Gastrointestinal Stromal Tumors (GISTs) are subepithelial lesions (SELs) that commonly develop in the gastrointestinal tract. GISTs, unlike other SELs, can exhibit malignant behavior, so differential diagnosis is critical to the decision-making process. Endoscopic ultrasound (EUS) is considered the most accurate imaging method for diagnosing and differentiating SELs in the gastrointestinal tract by assessing the lesions precisely and evaluating their malignant risk. Due to their overlapping imaging characteristics, endosonographers may have difficulty distinguishing GISTs from other SELs using conventional EUS alone, and the collection of tissue samples from these lesions may be technically challenging. Even though it appears to be less effective in the case of smaller lesions, histology is now the gold standard for achieving a final diagnosis and avoiding unnecessary and invasive treatment for benign SELs. The use of enhanced EUS modalities and elastography has improved the diagnostic ability of EUS. Furthermore, recent advancements in artificial intelligence systems that use EUS images have allowed them to distinguish GISTs from other SELs, thereby improving their diagnostic accuracy.

Feasibility of Continuous Monitoring of Endoscopy Performance and Adverse Events: A Single-Center Experience

BACKGROUND

We integrated a standardized questionnaire focusing on adverse events and performance measures in gastrointestinal endoscopy as a mandatory component of the electronical medical record.

METHODS

This retrospective study was conducted using prospectively collected data on quality parameters and adverse events (AEPM) for all diagnostic and therapeutic endoscopic procedures at our center between 2018 and 2020.

RESULTS

A total of 7532 consecutive endoscopic procedures were performed in 5035 patients. The proportion of high-risk examinations and high-risk patients was 20% and 23%, respectively. Severe adverse events (AEs, n = 21) occurred in 0.3% of procedures and significantly more often in patients with an ASA score > II (0.6%, p < 0.01). We observed no long-term morbidity after severe AEs. Mortality was 0.03% (n = 2). Following screening colonoscopy (n = 242), four endoscopists documented AEPM in more than 98% of the examinations. The cecal intubation rate was 97%, and the mean adenoma detection rate 60%. The quality of lavage was documented in 97% (rated as good in 70% and moderate in 24%).

CONCLUSIONS

The risk of adverse events is significantly increased in patients with an ASA score > II, which should be considered when choosing treatment methods and precautionary measures. Continuous recording of AEPM can be effectively integrated into the clinical reporting process, enabling analysis of the data and feedback to be provided to endoscopists.

Survival nomograms for colorectal carcinoma patients with lung metastasis and lung-only metastasis, based on the SEER database and a single-center external validation cohort

Background

We analysed the survival of colorectal cancer (CRC) patients with lung metastasis and lung-only metastasis and determined the risk factors for lung metastasis in CRC patients.

Methods

Data from colorectal cancer patients with lung metastasis diagnosed from 2010 to 2015 were obtained from the SEER database. Survival was analysed using the Kaplan–Meier method and log-rank test, the Cox proportional hazards regression model, and a competing risk model. The predictive ability of the nomgram was assessed by the concordance index (C-index) and calibration curves. The data from the SEER database for the period 2016–2019 was used as an external validation set. The characteristics of 70 CRC patients treated at Shanghai East Hospital between 2016 and 2019 were retrospectively analysed and data from China was chosen as an external validation set.

Results

The median survival time for colorectal cancer patients with lung metastasis was 12 months, while this value was 24 months in patients with lung-only metastasis. Among all CRC patients with lung metastasis, age, grade, T stage, N stage, presence of liver, brain or bone metastasis, anatomic site and surgery were related to overall survival (OS). In CRC patients with lung-only metastasis, age, T stage, marital status, chemotherapy and surgery were independent prognostic factors affecting OS. Two nomograms predicting OS were established, with great discrimination (C-index between 0.67 and 0.81) and excellent calibration. Factors including age, race, sex, tumour grade, T stage, N stage, presence of liver, brain or bone metastasis, marital status, insurance status and anatomic location were related to the occurrence of lung metastasis in CRC patients.

Conclusion

We developed two reliable clinical prediction models among CRC patients to predict the OS rates in patients with lung metastasis and lung metastasis only.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02547-9.

Incidence of colorectal cancer at different screening intervals after index colonoscopy and post-polypectomy: a meta-analysis of 811,181 participants

OBJECTIVES

To examine the evidence on the incidence of colorectal cancers (CRCs) at a follow-up screening colonoscopy (after index colonoscopy and post-polypectomy) in individuals with no adenoma, low-risk adenomas, and high-risk adenomas.

METHODS

We included studies reporting the incidence of CRCs at different screening intervals after index colonoscopy and post-polypectomy. The main outcome was pooled cumulative incidence rate of CRCs stratified by intervals of 3, 5, 10, and >10 years.

RESULTS

Fourteen studies with 811,181 participants were analyzed, including 10 multicenter studies and 3 national CRC screening programs. The cumulative incidence of CRCs was 0.63% (95% confidence interval [CI]: 0.30, 0.97) in the high-risk-adenoma group at 3 years, 0.37% (95% CI: 0.13, 0.61) and 0.67% (95% CI: 0.36, 0.99) in the low-risk-adenoma group at 5 and 10 years, respectively, and 0.32% (95% CI: 0.20, 0.45) and 0.50% (95% CI: 0.30, 0.69) in the no-adenoma-group at 10 and >10 years, respectively.

CONCLUSION

This meta-analysis summarizes the results of colonoscopy surveillance programs with detailed data support for different screening intervals. The data on date suggest that reasonable surveillance intervals are within 3 years for the high-risk-adenoma group, 5-10 years for the low-risk-adenoma group, and ≥10 years for the no-adenoma group.

Clinical outcomes of endoscopic submucosal dissection for colorectal neoplasms: A single-center experience in Southern Taiwan

Background and aims

Endoscopic submucosal dissection (ESD) as an advanced endoscopic procedure can be considered for the removal of colorectal lesions with high suspicion of limited submucosal invasion or cannot be optimally removed by snare-based techniques. We aimed to analyze the clinical outcomes of ESD for colorectal neoplasms in our hospital.

Methods

We retrospectively enrolled 230 patients with 244 colorectal neoplasms who received ESD procedures from April 2012 to October 2020 at Kaohsiung Chang Gung Memorial Hospital. Clinicopathological data were collected by chart review. We also recorded ESD-related complications and clinical outcomes.

Results

The average age was 64 years old, with a mean follow-up time of 22.59 months. There was a loss of follow-up in 34 lesions. Most lesions were lateral spreading tumors of the non-granular type. The average ESD time was 51.9 minutes. Nine cases (3.7%) had procedure-related complications, including two intra-procedure perforations (0.8%) and seven delayed bleeding (2.9%) without procedure-related mortality. 241 lesions (98.8%) achieved en-bloc resection, while 207 lesions (84.8%) achieved R0 resection. Most lesions were tubulo-(villous) adenoma. Malignancy included 35 adenocarcinomas and 5 neuroendocrine tumors. No local recurrence was developed during follow-up. Multivariate analysis for long ESD time revealed significance in size ≥ 10 cm² and endoscopist’s experience < 3 years. Pre-ESD endoscopic ultrasound revealed good prediction in discrimination of mucosal (sensitivity: 0.90) and submucosal lesion (specificity: 0.67).

Conclusions

ESD for colorectal neoplasms is an effective and safe technique. Size ≥ 10 cm² and endoscopist’s experience < 3 years were significantly associated with long procedure time. Pre-ESD EUS provided a good prediction for colorectal neoplasms in invasion depth.

Developing a Simple Score for Diagnosis of Acute Cholecystitis at the Emergency Department

We aim to develop a diagnostic score for acute cholecystitis that integrates symptoms, physical examinations, and laboratory data to help clinicians for timely detection and early treatment of this disease. We retrospectively collected data from our database from 2010 to 2020. Patients with acute abdominal pain who underwent an ultrasound or computed tomography (CT) scan at the emergency department (ED) were included. Cases were identified by pathological, CT, or ultrasound reports. Non-cases were those who did not fulfill any of these criteria. Multivariable regression analysis was conducted to identify predictors of acute cholecystitis. The model included 244 patients suspected of acute cholecystitis. Eighty-six patients (35.2%) were acute cholecystitis confirmed cases. Five final predictors remained within the reduced logistic model: age < 60, nausea and/or vomiting, right upper quadrant pain, positive Murphy’s sign, and AST ≥ two times upper limit of normal. A practical score diagnostic performance was AuROC 0.74 (95% CI, 0.67−0.81). Patients were categorized with a high probability of acute cholecystitis at score points of 9−12 with a positive likelihood ratio of 3.79 (95% CI, 1.68−8.94). ED Chole Score from these five predictors may aid in diagnosing acute cholecystitis at ED. Patients with an ED Chole Score >8 should be further investigated.

Development and validation of a risk score for prediction of clinical success after duodenal stenting for malignant gastric outlet obstruction

BACKGROUND

To develop and validate a risk score for predicting clinical success after duodenal stenting using self-expanding metallic stents (SEMS) for malignant gastric outlet obstruction (GOO).

RESEARCH DESIGN AND METHODS

Consecutive patients who underwent duodenal stenting for malignant GOO were evaluated. Potential predictors of clinical success were determined by uni/multivariate logistic regression analysis.Multiplication of the regression coefficients of the logistic regression model by a factor of two and rounding to obtain easy-to-use point numbers enabling the calculation of the score. Using 10-fold cross-validation, the model was internally validated.

RESULTS

One hundred twelve patients were included. Clinical success was achieved in 93 (83.0%) patients. On multivariate logistic regression, selected age ≤65 years (p = 0.05, 1.5 points), stenosis type I (p = 0.04, 3 points), and pancreatic cancer (p = 0.01, 3.5 points) were significant predictors of clinical success. On the Receiver Operating Characteristic (ROC) analysis, a score of 5 had higher specificity and sensitivity.

CONCLUSION

Our score could be useful at identifying, among poor surgical candidates, patients more likely to benefit from SEMS.

Post-polypectomy colonoscopy surveillance: Can we improve the diagnostic yield?

Although adenomas and serrated polyps are the preneoplastic lesions of colorectal cancer, only few of them will eventually progress to cancer. This review provides a comprehensive overview of the present and future of post-polypectomy colonoscopy surveillance. Post-polypectomy surveillance guidelines have recently been updated and all share the aim towards more selective and less frequent surveillance. We have examined these current guidelines and compared the recommendations of each of them. To improve the diagnostic yield of post-polypectomy surveillance it is important to find predictors of metachronous polyps that better identify high-risk individuals of developing advanced neoplasia. For this reason, we have also conducted a literature review of the molecular biomarkers of metachronous advanced colorectal polyps. Finally, we have discussed future directions of post-polypectomy surveillance and identified possible strategies to improve the use of endoscopic resources with the COVID-19 pandemic.

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.

Risk factors for recurrence of colorectal conventional adenoma and serrated polyp

Background

Removal of colorectal polyps during screening could reduce the incidence of colorectal cancer (CRC). However, there is a lack of data on risk factors associated with recurrence of polyps, including conventional adenomas and serrated polyps (SPs). This study aimed to determine risk factors for recurrence of colorectal polyps and their subtypes based on the characteristics of the patients and polyps.

Methods

A total of 1,165 patients diagnosed with conventional adenoma or SP in the Sixth Affiliated Hospital of Sun Yat-sen University between January 2013 and December 2019 were enrolled in this study, including 668 cases with conventional adenomas, 385 with SPs, and 112 with coexistence of adenomas and SPs. Univariate analysis and multivariate logistic regression were used to identify potential risk factors for polyp recurrence. A nomogram was established according to risk factors and the performance was evaluated using calibration plots.

Results

During a median follow-up of 24 months, recurrent polyps were observed in 531 (45.6%) cases. Male, age ≥50 years, body mass index (BMI) ≥24 kg/m², at least three polyps, smoking, alcohol consumption, family history of polyps, and family history of CRC were independent risk factors for polyp recurrence. The Harrell’s C-index of the nomogram developed with these parameters was 0.69 and the calibration plots showed good agreement between actual polyp recurrence and nomogram-predicted recurrence probability. In the subtype analyses, conventional adenomas had the same risk factors for recurrence as all polyps, while smoking, alcohol consumption, family history of polyps, and family history of CRC were not risk factors for SP recurrence.

Conclusions

We identified several risk factors for recurrence of colorectal polyps and found that some of them could increase the risk of adenoma recurrence but not SP recurrence, including smoking, alcohol consumption, and family history of polyps/CRC, which might help us to understand different etiology and biology between conventional adenomas and SPs.

Novel Methods of Risk Stratifying Patients for Metachronous, Pre-Malignant Colorectal Polyps: A Systematic Review

INTRODUCTION

Despite conventional measures of future polyp risk (histology, dysplasia, size, number), surveillance places a burden on patients and colonoscopy services. We aimed to review novel risk stratification techniques.

METHODS

A systematic literature review was performed for studies using genomics, transcriptomics, IHC or microbiome as markers of metachronous polyp risk.

RESULTS

4165 papers underwent title, 303 abstract and 215 full paper review. 25 papers were included. 49 mutations/ SNPs/ haplotypes in 23 genes/ chromosomal regions (KRAS, APC, EGFR, COX1/2, IL23R, DRD2, CYP2C9/24A1/7A1, UGT1A6, ODC, ALOX12/15, PGDH, SRC, IGSF5, KCNS3, EPHB1/ KY, FAM188b, 3p24.1, 9q33.2, 13q33.2) correlated with metachronous adenoma / advanced adenoma risk. Expression levels of 6 proteins correlated with metachronous adenoma (p53, β-catenin, COX2, Adnab-9, ALDH1A1) or sessile serrated polyp (ANXA10) risk.

CONCLUSION

Although genomic and IHC markers correlated with metachronous polyp risk, it seems likely that a panel of novel markers will be required to refine this risk.

Risk Factors for Recurrent Colorectal Polyps

The recurrence of colorectal polyps is caused by various factors and leads to the carcinogenesis of colorectal cancer, which ranks third in incidence and fourth in mortality among cancers worldwide. The potential risk factors for colorectal polyp recurrence have been demonstrated in multiple trials. However, an article that pools and summarizes the various results is needed. This review enumerates and analyzes some risk factors in terms of patient characteristics, procedural operations, polyp characteristics, and dietary aspects to propose some effective prophylactic measures. This review aimed to provide a reference for clinical application and guide patients to prevent colorectal polyp recurrence in a more effective manner.

Recurrence with malignancy after endoscopic resection of large colon polyps with high-grade dysplasia: incidence and risk factors

BACKGROUND

In the West, piecemeal endoscopic resection remains the primary treatment for large colon polyps (LCP), as most recurrences are believed to be benign and resectable with follow-up endoscopy. However, invasive malignancy at the site of prior piecemeal endoscopic mucosal resection has been reported in the Asian literature. This study aims to identify the incidence of and the risk factors for local recurrence with malignancy after endoscopic resection of LCP with high-grade dysplasia (HGD).

METHODS

In this retrospective cohort study, we identified patients undergoing complete endoscopic resection of LCPs (≥ 20 mm) with HGD at the Cleveland Clinic between January 2000 and December 2016. Demographic, endoscopic, and pathologic data were collected. All subsequent endoscopic and pathology reports were reviewed to identify recurrence. The cumulative incidence of malignancy at the polypectomy site was determined and univariate analysis was performed to assess risk factors.

RESULTS

A total of 254 LCPs with HGD were resected in 229 patients. Mean polyp size was 29.2 mm. There were 138 lesions resected in piecemeal fashion and 116 en-bloc. After a median follow-up of 28.7 months for the entire cohort, local recurrence with malignancy was diagnosed in six cases. Median time to malignancy diagnosis was 28.5 months. All malignant cases occurred after piecemeal resection and none after en-bloc resection (HR 11.4; 95% CI 0.48-273).

CONCLUSION

Malignancy after endoscopic resection of LCPs with HGD is uncommon and may be associated with piecemeal resection. When possible, en-bloc resection should be the goal for the management of LCPs.

Cap-fitted endoscopic mucosal resection of ≥ 20 mm colon flat lesions followed by argon plasma coagulation results in a low adenoma recurrence rate

Background and study aims  Endoscopic mucosal resection (EMR) is increasingly used for the treatment of large colonic polyps (≥ 20 mm). A drawback of EMR is local adenoma recurrence. Therefore, we studied the impact of argon plasma coagulation (APC) of the EMR edge on local adenoma recurrence. Patients and methods  This was a retrospective study of patients with laterally spreading tumors (LST) ≥ 20 mm, who underwent EMR from January 2009 to August 2018 and follow-up endoscopic assessment. A cap-fitted endoscope was used to assess completeness of resection by systematically inspecting the EMR defect for any macroscopic disease. This was followed by forced APC of the resection edge followed by clip closure of the defect. Surveillance colonoscopy was performed at 6 months after resection to detect recurrence. Results  Two hundred forty-six patients met the inclusion criteria. Most were female (53 %) and white (80 %), with a Median age of 64 years. Median polyp size was 35 mm (interquartile range, 30-45 mm). Most polyps were located in the right colon (77 %) and were removed by piecemeal EMR (70 %). Eleven patients (5 %) had residual tumor at the resection site. Conclusions  We observed low adenoma recurrence after argon plasma coagulation of the EMR edge with a cap fitted colonoscope in patients with LST ≥ 20 mm of the colon, which requires further validation in a randomized controlled study.

British Society of Gastroenterology/Association of Coloproctology of Great Britain and Ireland/Public Health England post-polypectomy and post-colorectal cancer resection surveillance guidelines

These consensus guidelines were jointly commissioned by the British Society of Gastroenterology (BSG), the Association of Coloproctology of Great Britain and Ireland (ACPGBI) and Public Health England (PHE). They provide an evidence-based framework for the use of surveillance colonoscopy and non-colonoscopic colorectal imaging in people aged 18 years and over. They are the first guidelines that take into account the introduction of national bowel cancer screening. For the first time, they also incorporate surveillance of patients following resection of either adenomatous or serrated polyps and also post-colorectal cancer resection. They are primarily aimed at healthcare professionals, and aim to address:Which patients should commence surveillance post-polypectomy and post-cancer resection?What is the appropriate surveillance interval?When can surveillance be stopped? two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps The Appraisal of Guidelines for Research and Evaluation (AGREE II) instrument provided a methodological framework for the guidelines. The BSG's guideline development process was used, which is National Institute for Health and Care Excellence (NICE) compliant.two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps The key recommendations are that the high-risk criteria for future colorectal cancer (CRC) following polypectomy comprise either:two or more premalignant polyps including at least one advanced colorectal polyp (defined as a serrated polyp of at least 10 mm in size or containing any grade of dysplasia, or an adenoma of at least 10 mm in size or containing high-grade dysplasia); or five or more premalignant polyps This cohort should undergo a one-off surveillance colonoscopy at 3 years. Post-CRC resection patients should undergo a 1 year clearance colonoscopy, then a surveillance colonoscopy after 3 more years.

Long-term follow-up after EMR of large colorectal lesions: metachronous lesions, predictors and surveillance timing

Background: Endoscopic mucosal resection (EMR) is the first-line approach to large colorectal sessile lesions. These patients have been associated with high rates of metachronous lesions (ML), but long-term follow-up (LtFU) data are lacking. We aimed at evaluating the efficacy of an LtFU protocol and analyse the development and risk factors for ML.Methods: A prospectively collected database was analysed. Seventy-six patients submitted to EMR of large colorectal sessile lesions between 2007 and 2013 complied with a specific endoscopic surveillance, consisting of two protocols - initial follow-up (iFU) and LtFU. iFU intended to inspect the mucosectomy scars twice (at 3-6 and 12 months) and remove synchronous lesions (SL). Protocol examinations of LtFU were carried out at the first- and fourth-year post-iFU, aiming to remove ML. Statistical analysis included variables related to patient, index lesion, SL and ML characteristics.Results: Rates of ML were 39.5% and 20.4% at the first- and fourth-year of LtFU, and respectively 11.8% and 3.7% of them were advanced ML. All ML were endoscopically resectable. At univariate analysis, male gender (OR: 2.91; p=.029), the presence of SL (OR 3.86, p=.010) and advanced SL (OR 4.25, p=.006) were risk factors for ML. At multivariate analysis, male gender (p=.031) and advanced SL (p=.006) were significant predictors of ML development.Conclusions: We confirmed the increased risk of ML in patients with large colorectal lesions. A significant number of advanced ML was removed at the first LtFU colonoscopy, probably it should be carried out earlier than currently recommended.

Patients with Non-Hodgkin's Lymphoma Are at Risk of Adenomatous Colon Polyps

BACKGROUND

Patients with non-Hodgkin's lymphoma (NHL) are frequently referred for colonoscopy to evaluate gastrointestinal symptoms during their treatment course. Here, we described the rate of colonic adenomas in patients with NHL.

METHODS

This was a retrospective study of patients with NHL who underwent colonoscopy after being diagnosed with NHL between January 2000 and December 2017.

RESULTS

Of the 17,938 patients who had been diagnosed with NHL in the study period, 2176 met the inclusion criteria. The mean age at the time of colonoscopy was 61 years. Most patients were male (61%). Overall, 1273 polyps were detected in 811 patients (37%). Sessile serrated adenomas were detected in 102 (5%) patients. The overall ADR was 12% in patients younger than 40 years of age (n = 103), 26% in patients aged 40-50 (n = 251), 34% in patients aged 51-60 (n = 630), and 43% in patients older than 60 (n = 1212). Most polyps were located in the right colon (63%), and 101 (8%) were larger than 1 cm. Villous adenomatous features were present in 1% of polyps, while high-grade dysplasia was detected in 22%. Invasive adenocarcinoma was identified in 4%. The median interval from lymphoma diagnosis to adenoma detection was 1.4 years (interquartile range 0.5-3.8 years). A repeat colonoscopy was performed in 343 patients. The overall ADR on repeat colonoscopy was 30%. Cox regression analysis revealed that age (hazards ratio 1.04; 95% confidence interval 1.03-1.05; P < 0.001) and male sex (hazards ratio 1.35; 95% confidence interval 1.13-1.60; P = 0.001) were independent factors associated with worse overall survival. By contrast, screening colonoscopy was associated with longer survival duration (hazards ratio 0.48; 95% confidence interval 0.36-0.63; P < 0.001).

CONCLUSION

The ADR in NHL patients aged 40-50 years was equivalent to that reported in the literature in non-cancer patients aged 50-70 years. Early screening colonoscopy may be warranted in NHL patients younger than 50 years. Screening colonoscopy significantly improved the overall survival of patients with NHL.

The association between progression of coronary artery calcium and colorectal adenoma: A retrospective follow-up study of asymptomatic Koreans

The potential relationship between coronary artery calcium (CAC) and colorectal adenoma has been widely indicated. This study aimed to investigate the relationship between the risk of colorectal adenoma and CAC progression in asymptomatic Korean adults who underwent serial assessments by colonoscopy and CAC scan.A total of 754 asymptomatic participants, who had undergone serial CAC scans and colonoscopies for screening, were enrolled. Changes in CAC were assessed according to the absolute change between baseline and follow-up results. CAC progression was defined using Multi-Ethnic Study of Atherosclerosis method. Risk for adenoma at follow-up colonoscopy was determined using hazard ratio (HR) by Cox regression. The area under the receiver operating characteristic (ROC) curve was measured.The mean follow-up duration was 3.4 ± 2.5 years. CAC progression was found in 215 participants (28.5%). Participants with adenoma at index colonoscopy showed a higher rate of CAC progression than those without (38.8% vs 23.6%, P < .01). In participants with adenoma at index colonoscopy, CAC progression significantly increased the cumulative risk for adenoma at follow-up colonoscopy (HR = 1.48, 95% confidence interval [CI] 1.06-2.06, log-rank P = .021). In multivariate analysis, male sex (HR = 2.57, 95% CI 1.22-5.42, P = .013), ≥3 adenomas at index colonoscopy (HR = 2.60, 95% CI 1.16-5.85, P = .021), and CAC progression (HR = 2.74, 95% CI 1.48-5.08, P = .001) increased the risk of adenoma at follow-up colonoscopy. In participants without adenoma at index colonoscopy, neither baseline CAC presence nor CAC progression increased the risk of adenoma at follow-up colonoscopy. The interaction between CAC progression and adenoma at index colonoscopy was significant in multivariable model (P = .005). In the ROC analysis, AUC of CAC progression for adenoma at follow-up colonoscopy was 0.625 (95% CI 0.567-0.684, P < .001) in participants with adenoma at index colonoscopy.Participants with CAC progression, who are at high risk of coronary atherosclerosis, may need to be considered for follow-up evaluation of colorectal adenoma, especially those with adenoma at index colonoscopy.

Predictors of rectal adenoma recurrence following transanal endoscopic surgery: a retrospective cohort study

BACKGROUND

Transanal endoscopic surgery is the treatment of choice in patients with rectal adenomas that cannot be removed by endoscopy. However, the risk of adenoma recurrence and optimal surveillance is not well defined. The objective of this study was to characterize the timing and frequency of rectal adenoma recurrence after removal by transanal endoscopic surgery and identify recurrence risk factors.

METHODS

This was a retrospective cohort study of a large, single-center academic institution in Vancouver, BC, Canada. Consecutive patients between May 1, 2007 and September 30, 2016 with pathology-confirmed rectal adenoma treated by primary excision with transanal endoscopic surgery and at least 1 year of confirmed endoscopic follow-up were included. Main outcome measures were recurrence rates following TEM as well as risk factors for recurrence.

RESULTS

297 patients met inclusion criteria. The mean age of patients was 66.5 ± 11.5 years and 57.9% were male. Median follow-up was 623 (range 56-3841) days. A total of 62 recurrences occurred in 41 patients (13.8% of study population). Recurrences were managed with repeat transanal endoscopic surgery or endoscopic resection 67.7% and 25.8% of the time, respectively. Radical resection was required for adenocarcinoma in 4 patients. Recurrence-free survival rates were 93.4% at 1 year, 86.2% at 2 years, and 73.1% at 5 years. After adjusting for individual surgeons, adenoma height, size > 3 cm, high-grade dysplasia, positive margins, and management of the rectal defect, patients who underwent surgery in the latter 5 years of the study had lower odds of recurrence (OR 0.42, 95% CI 0.19, 0.93, p = 0.03).

CONCLUSIONS

Rectal adenomas managed by transanal endoscopic surgery are lesions at high risk for recurrence; surveillance should be performed within the first 2 years and continued for a total of at least 5 years. Most recurrences can be successfully treated with repeat TEM or endoscopic resection.

Response to repeat echoendoscopic celiac plexus neurolysis in pancreatic cancer patients: A machine learning approach

BACKGROUND

/Objectives: Efficacy of repeat echoendoscopic celiac plexus neurolysis is still unclear. Aim of the study was to assess the efficacy of repeat celiac plexus neurolysis and to build an artificial neural network model able to predict pain response.

METHODS

Data regarding 156 patients treated with repeat celiac plexus neurolysis between 2004 and 2019 were reviewed. Artificial neural network and logistic regression models were built to predict pain response after treatment. Performance of the models was expressed in terms of accuracy, positive predictive value, and positive likelihood ratio.

RESULTS

Median age was 62 years (range 39-86) and most patients were male (66%) with pre-procedural visual analogue score 7. Fifty-one patients (32.6%) experienced treatment response, of which 6 (3.8%) complete pain suppression. Median duration of pain relief was 6 (2-8) weeks. Tumoral stage, interval from initial to repeat treatment, response to initial neurolysis, and tumor progression between the two treatments resulted as significant predictors of pain response. The performance of the artificial neural network in predicting treatment response was higher than regression model (area under the curve: 0.94, 0.89-0.97 versus 0.85, 0.78-0.89; p < 0.001). Positive predictive value and positive likelihood ratio resulted 90.3% and 19.35, respectively. Classification error rate was 5.7% with the artificial neural network compared to 14.7% of regression model (p < 0.001). These findings were confirmed through ten-fold cross validation.

CONCLUSIONS

Pain response following repeat neurolysis is generally less pronounced than after initial treatment. Artificial neural network may help to identify those subjects likely to benefit from repeat neurolysis.

Prediction of Recurrence-associated Death from Localized Prostate Cancer with a Charlson Comorbidity Index-reinforced Machine Learning Model

Research has failed to resolve the dilemma experienced by localized prostate cancer patients who must choose between radical prostatectomy (RP) and external beam radiotherapy (RT). Because the Charlson Comorbidity Index (CCI) is a measurable factor that affects survival events, this research seeks to validate the potential of the CCI to improve the accuracy of various prediction models. Thus, we employed the Cox proportional hazard model and machine learning methods, including random forest (RF) and support vector machine (SVM), to model the data of medical records in the National Health Insurance Research Database (NHIRD). In total, 8581 individuals were enrolled, of whom 4879 had received RP and 3702 had received RT. Patients in the RT group were older and exhibited higher CCI scores and higher incidences of some CCI items. Moderate-to-severe liver disease, dementia, congestive heart failure, chronic pulmonary disease, and cerebrovascular disease all increase the risk of overall death in the Cox hazard model. The CCI-reinforced SVM and RF models are 85.18% and 81.76% accurate, respectively, whereas the SVM and RF models without the use of the CCI are relatively less accurate, at 75.81% and 74.83%, respectively. Therefore, CCI and some of its items are useful predictors of overall and prostate-cancer-specific survival and could constitute valuable features for machine-learning modeling.

Local Recurrence and Its Risk Factor after Incomplete Resection of Colorectal Advanced Adenomas: A Single Center, Retrospective Study

Background/Aims

Colonoscopy can detect precancerous lesions, which can subsequently be removed and reduce incidences of and mortality from colorectal cancer (CRC). However, recently published data have highlighted a significant rate of CRC in patients who previously underwent colonoscopy. Among many reasons, incomplete resection has been considered as a significant contributor. However, to date, there have only been a few studies regarding incompletely resected polyps, especially advanced colorectal adenoma (ACA). Hence, we aimed to evaluate the prognosis of incompletely resected ACA.

Methods

We retrospectively reviewed the medical records of patients with ACA who had underwent endoscopic treatment with incomplete resection. The primary outcomes were (1) the incomplete resection rate of ACA, as determined by a histopathologic examination and (2) the recurrence rate of incompletely resected ACA. We also investigated the probable contributing factors that may have led to a relapse of incompletely resected ACA.

Results

A total of 7,105 patients had their colorectal polyps resected by endoscopic treatment, and 2,233 of these were considered as ACA. Of these, 354 polyps (15.8%) were resected incompletely, and only 163 patients were followed-up. Of those followed-up, 31 patients (19.0%) experienced local recurrence. The risk factors for recurrence after incomplete resection were evaluated; age, morphology of adenoma, and use of rescue therapy, such as argon plasma coagulation, were found to be associated with adenoma recurrence.

Conclusions

Incompletely resected ACA in older patients or in patients with sessile-type adenomas should be monitored strictly, and if incomplete resection is suspected, rescue therapy must be considered.

Determining the optimal surveillance interval after a colonoscopic polypectomy for the Korean population?

Background/Aims

Western surveillance strategies cannot be directly adapted to the Korean population. The aim of this study was to estimate the risk of metachronous neoplasia and the optimal surveillance interval in the Korean population.

Methods

Clinical and pathological data from index colonoscopy performed between June 2006 and July 2008 and who had surveillance colonoscopies up to May 2015 were compared between low- and high-risk adenoma (LRA and HRA) groups. The 3- and 5-year cumulative risk of metachronous colorectal neoplasia in both groups were compared.

Results

Among 895 eligible patients, surveillance colonoscopy was performed in 399 (44.6%). Most (83.3%) patients with LRA had a surveillance colonoscopy within 5 years and 70.2% of patients with HRA had a surveillance colonoscopy within 3 years. The cumulative risk of metachronous advanced adenoma was 3.2% within 5 years in the LRA group and only 1.7% within 3 years in the HRA group. The risk of metachronous neoplasia was similar between the surveillance interval of <5 and ≥5 years in the LRA group; however, it was slightly higher at surveillance interval of ≥3 than <3 years in the HRA group (9.4% vs. 2.4%). In multivariate analysis, age and the ≥3-year surveillance interval were significant independent risk factors for metachronous advanced adenoma (P=0.024 and P=0.030, respectively).

Conclusions

Patients had a surveillance colonoscopy before the recommended guidelines despite a low risk of metachronous neoplasia. However, the risk of metachronous advanced adenoma was increased in elderly patients and those with a ≥3-year surveillance interval.

Giant tubular adenoma with malignancy clinical characteristics in a female teenager: Case report and a review of the literature

BACKGROUND

Adenomas of the colon are usually benign tumors which carry a tendency for malignancy. These tumors can be villous, tubular, tubulovillous, or sessile serrated. Those with adenomatous structure can develop malignant characteristics in 1.5% to 9.4% of cases.

METHODS

We present a case report of a 16-year-old female adolescent with an adenoma of the descending colon. History revealed prolonged diarrheic syndrome for the past 6 months, repeated headache, and a weight loss of ∼5 kg in the past month. One week before the admission, the patient presented an episode of inferior digestive hemorrhage.

RESULTS

On admission laboratory tests revealed iron deficiency anemia, and a mildly increased erythrocyte sedimentation rate. The abdominal ultrasound revealed an inhomogeneous mass of the descending colon and 2 hyperechoic lesions in the liver. The colonoscopy showed a tumor of the descending colon, a tubular adenoma according to the pathological examination. Additionally, we noted an atypical presentation of the tumor and the signs of mild dysplasia identified at the pathological examination.

CONCLUSION

Weight loss, bowel transit alterations, loss of appetite, and inferior hemorrhage in an adolescent can be symptoms of a benign or malignant tumor of the colon.

Development and validation of a risk score for advanced colorectal adenoma recurrence after endoscopic resection

AIM: To develop and validate a risk score for advanced colorectal adenoma (ACA) recurrence after endoscopic polypectomy.

METHODS: Out of 3360 patients who underwent colon polypectomy at University of Foggia between 2004 and 2008, data of 843 patients with 1155 ACAs was retrospectively reviewed. Surveillance intervals were scheduled by guidelines at 3 years and primary endpoint was considered 3-year ACA recurrence. Baseline clinical parameters and the main features of ACAs were entered into a Cox regression analysis and variables with P < 0.05 in the univariate analysis were then tested as candidate variables into a stepwise Cox regression model (conditional backward selection). The regression coefficients of the Cox regression model were multiplied by 2 and rounded in order to obtain easy to use point numbers facilitating the calculation of the score. To avoid overoptimistic results due to model fitting and evaluation in the same dataset, we performed an internal 10-fold cross-validation by means of bootstrap sampling.

RESULTS: Median lesion size was 16 mm (12-23) while median number of adenomas was 2.5 (1-3), whereof the number of ACAs was 1.5 (1-2). At 3 years after polypectomy, recurrence was observed in 229 ACAs (19.8%), of which 157 (13.5%) were metachronous neoplasms and 72 (6.2%) local recurrences. Multivariate analysis, after exclusion of the variable “type of resection” due to its collinearity with other predictive factors, confirmed lesion size, number of ACAs and grade of dysplasia as significantly associated to the primary outcome. The score was then built by multiplying the regression coefficients times 2 and the cut-off point 5 was selected by means of a Receiver Operating Characteristic curve analysis. In particular, 248 patients with 365 ACAs fell in the higher-risk group (score ≥ 5) where 3-year recurrence was detected in 174 ACAs (47.6%) whereas the remaining 595 patients with 690 ACAs were included in the low-risk group (score < 5) where 3-year recurrence rate was 7.9% (55/690 ACAs). Area under the curve of the model was 0.81 (0.72-0.86) with an overall classification error rate of 0.09. The model was finally validated by means of 10-fold cross validation.

CONCLUSION: Our study provides support for the use of a novel risk score as a clinical predictor of ACA recurrence after colon polypectomy.