Prevalence, distribution, and risk factor for colonic neoplasia in 1133 subjects aged 40-49 undergoing screening colonoscopy

Should we perform sigmoidoscopy for colorectal cancer screening in people under 45 years?

BACKGROUND

The strategy for preventing colorectal cancer is screening by colonoscopy, which offers a direct way for detection and removal of adenomatous polyps (APs). American College of Gastroenterology guidelines recommend that people aged ≥ 45 years should undergo colonoscopy; however, how to deal with people aged ≤ 45 years is still unknown.

AIM

To compare the prevalence of APs and high-grade neoplasia between the left and right colon in patients ≤ 45 years.

METHODS

A retrospective observational study was conducted at a single tertiary III hospital in China. This study included patients aged 18-45 years with undergoing initial colonoscopy dissection and pathological diagnosis AP or high-grade neoplasia between February 2014 and January 2021. The number of APs in the entire colon while screening and post-polypectomy surveillance in following 1-3 years were evaluated.

RESULTS

A total of 3053 cases were included. The prevalence of APs in the left and right colon was 55.0% and 41.6%, respectively (OR 1.7, 95%CI 1.6-2.4; P < 0.05). For APs with high-grade neoplasia, the prevalence was 2.7% and 0.9%, respectively (OR 3.0, 95%CI 2.0-4.6; P < 0.05). Therefore, the prevalence of APs and high-grade neoplasia in the left colon was significantly higher than in the right colon in patients aged ≤ 45 years. There were 327 patients who voluntarily participated in post-polypectomy surveillance in following 1-3 years, and APs were found in 216 cases (66.1%); 170 cases had 1-3 polyps (52.0%) and 46 cases had > 3 polyps (14.1%; OR 0.3, 95%CI 0.1-0.6; P < 0.05).

CONCLUSION

This study suggests that flexible sigmoidoscopy would be an optimal approach for initial screening in people aged ≤ 45 years and would be a more cost-effective and safe strategy.

Prevalence of Colonic Polyps Detected by Colonoscopy in Symptomatic Patients and Comparison Between Different Age Groups. What Age Should be Considered for Investigation?

<b>Introduction:</b> The Burden of Colorectal cancer (CRC) as one of the most common malignancies is considerable worldwide, with 1.8 million diagnoses each year. Although it is well established that most CRCs arise from colonic polyps, guidelines and recommendations indicate different ages as starting points for endoscopic examination of the colon, either as cancer screening programs or in symptomatic patients. Most standard guidelines adapt the cut-off age of 50. However, this has been challenged by the results of recent studies. This multicentric prospective study aimed to investigate the frequency, distribution, and histopathological findings of colonic polyps in patients who underwent colonoscopy with special attention to the age group of 40-49-year-olds compared with 50-59 in the population.</br></br> <b>Material and methods:</b> This multicentric, prospective study was designed to enroll adult patients referred to three universityaffiliated endoscopy units. As many as 723 patients met all the inclusion criteria. Data analysis was performed on endoscopic and histopathological characteristics of all detected lesions, including colonic polyps and neoplastic lesions.</br></br> <b>Results:</b> A total of 723 patients with a mean age of 46.03 (16.8) years were included in this study. Rectal bleeding was the most frequent symptom (40.9%). One hundred and thirteen patients (15.6%) were found to have colonic polyps, and 11 cases (1.52%) of CRC were detected. Most polyps were located in the left colon (67.5%). There was no statistical difference in the prevalence of adenomatous polyps between the age group of 40-49 years and 50-59 years (P = 0.77). Detailed examination of data using receiver operating characteristic (ROC) curve analysis not only showed age is a risk factor for the presence of colonic polyps but also revealed the cut-off age of 42.5 for the presence of all types of colonic polyps (44.5 years for adenomatous polyps).</br></br> <b>Conclusion:</b> This study has showed a similar polyp prevalence in the age group of 40-49 years as compared to 50-59. Our study suggests that appropriate colon examination should be performed at a younger age to achieve early detection of colonic polyps, specifically in patients with red flag symptoms.

Construction and validation of nomograms combined with novel machine learning algorithms to predict early death of patients with metastatic colorectal cancer

Purpose

The purpose of this study was to investigate the clinical and non-clinical characteristics that may affect the early death rate of patients with metastatic colorectal carcinoma (mCRC) and develop accurate prognostic predictive models for mCRC.

Method

Medical records of 35,639 patients with mCRC diagnosed from 2010 to 2019 were obtained from the SEER database. All the patients were randomly divided into a training cohort and a validation cohort in a ratio of 7:3. X-tile software was utilized to identify the optimal cutoff point for age and tumor size. Univariate and multivariate logistic regression models were used to determine the independent predictors associated with overall early death and cancer-specific early death caused by mCRC. Simultaneously, predictive and dynamic nomograms were constructed. Moreover, logistic regression, random forest, CatBoost, LightGBM, and XGBoost were used to establish machine learning (ML) models. In addition, receiver operating characteristic curves (ROCs) and calibration plots were obtained to estimate the accuracy of the models. Decision curve analysis (DCA) was employed to determine the clinical benefits of ML models.

Results

The optimal cutoff points for age were 58 and 77 years and those for tumor size of 45 and 76. A total of 15 independent risk factors, namely, age, marital status, race, tumor localization, histologic type, grade, N-stage, tumor size, surgery, radiation, chemotherapy, bone metastasis, brain metastasis, liver metastasis, and lung metastasis, were significantly associated with the overall early death rate of patients with mCRC and the cancer-specific early death rate of patients with mCRC, following which nomograms were constructed. The ML models revealed that the random forest model accurately predicted outcomes, followed by logistic regression, CatBoost, XGBoost, and LightGBM models. Compared with other algorithms, the random forest model provided more clinical benefits than other models and can be used to make clinical decisions in overall early death and specific early death caused by mCRC.

Conclusion

ML algorithms combined with nomograms may play an important role in distinguishing early deaths owing to mCRC and potentially help clinicians make clinical decisions and follow-up strategies.

Value of routine test for identifying colorectal cancer from patients with nonalcoholic fatty liver disease

Background

Nonalcoholic fatty liver disease (NAFLD) is a risk factor for colorectal neoplasms. Our goal is to explore the relationship between NAFLD and colorectal cancer (CRC) and to analyze potential indicators for screening CRC in NAFLD based on clinical big data.

Methods

Demographic information and routine clinical indicators were extracted from Xiangya Medical Big Data Platform. 35,610 NAFLD cases without CRC (as group NAFLD-CRC), 306 NAFLD cases with CRC (as group NAFLD-NonCRC) and 10,477 CRC cases without NAFLD were selected and evaluated. The CRC incidence was compared between NAFLD population and general population by Chi-square test. Independent sample t-test was used to find differences of age, gender and routine clinical indicators in pairwise comparisons of NAFLD-CRC, NAFLD-NonCRC and nonNAFLD-CRC.

Results

NAFLD population had a higher CRC incidence than general population (7.779‰ vs 3.763‰, P < 0.001). Average age of NAFLD-CRC (58.79 ± 12.353) or nonNAFLD-CRC (59.26 ± 13.156) was significantly higher than NAFLD-nonCRC (54.15 ± 14.167, p < 0.001). But age had no significant difference between NAFLD-CRC and nonNAFLD-CRC (P > 0.05). There was no different gender distribution for three groups (P > 0.05). NAFLD-CRC had lower anaemia-related routine clinical indicators such as decrease of red blood cell count, mean hemoglobin content and hemoglobin than NAFLD-nonCRC (P < 0.05 for all). Anemia of NAFLD-CRC was typical but it might be slighter than nonNAFLD-CRC. More interestingly, NAFLD-CRC had distinct characteristics of leukocyte system such as lower white blood cell count (WBC) and neutrophil count (NEU_C) and higher basophil percentage (BAS_Per) than nonNAFLD-CRC and NAFLD-nonCRC (P < 0.05 for all). Compared with NAFLD-nonCRC, the change of WBC, BAS_Per and NEU_C in NAFLD-CRC was different from that in nonNAFLD-CRC. In addition, NAFLD-CRC had a higher level of low density lipoprotein (LDL) and high density lipoprotein (HDL), lower level of triglyceride (TG) and Albumin-to-globulin ratio (A/G) than NFLD-nonCRC (P < 0.05 for all).

Conclusions

NAFLD is associated with a high incidence of CRC. Age is an important factor for CRC and the CRC incidence increases with age. Anemia-related blood routine clinical indicators, leukocyte system and blood lipid indicators may be more important variables for identifying CRC in NAFLD. So blood routine test and liver function/blood lipid test are valuable for screening CRC in NAFLD.

A Review of the Management of Sporadic Colorectal Adenomas in Young People: Is Surveillance Wasted on the Young?

The national incidence of colorectal cancer is increasing in people younger than 50 years old. Although diagnostic colonoscopy is detecting more sporadic adenomas in young adults, there are no guidelines for post-polypectomy surveillance. The aim of this review was to survey the medical literature on the prevalence of sporadic adenomas in young adults, subsequent risk of metachronous neoplasia, and lastly to provide several concluding recommendations for clinical practice. We found that the prevalence of sporadic adenomas in young adults is greater than initially estimated and dependent upon factors such as colonoscopy indication and age. The incidence of metachronous colorectal neoplasia following polypectomy is unclear but does not appear to be greater than that of older adults. Risk factors for metachronous neoplasia include findings on index colonoscopy, male gender, smoking status, and certain medical comorbidities. Upon finding a colorectal adenoma in a young person, we suggest that a detailed family history be obtained to confirm that it is truly sporadic. Testing adenomas for evidence of Lynch syndrome is low yield. Strategies to inform surveillance intervals may include an assessment of risk factors for metachronous neoplasia, although surveillance intervals shorter than those recommended in current guidelines are not warranted. Future research should focus on obtaining long-term, prospective data on the incidence of metachronous neoplasia in diverse patient populations.

A Comparative Study Evaluating the Incidence of Colorectal Neoplasia(s) in Candidates for Bariatric Surgery by Screening Colonoscopy, 40-49 Versus 50-65 Years Old: a Preliminary Study

INTRODUCTION

Obesity and metabolic syndrome (MetS) are associated with colorectal neoplasia (CRN) and carcinoma (CRC). Whether such subjects must undergo screening colonoscopy (SC) earlier, is unknown. Incidences of CRNs in 40-49- versus 50-65-year-old bariatric patients were compared by SC. No prospective data on SC is available in morbidly obese/MetS.

MATERIAL AND METHODS

Surgical weight loss candidates over 39 years of age, asymptomatic, and average-risk for CRC offered SC. Those giving written informed consent were enrolled. Colonoscopies were done by the same surgeon. Smoking/drinking history, fasting blood glucose (FBG), insulin, C-peptide, triglyceride, high density lipoprotein, vitamin D, HbA1c, and insulin resistance parameters were recorded. CRN rate and the distribution of variables in patients 40-49 years of age were compared with 50-65. Student's t and Chi-square tests were used as appropriate. P < 0.05 was regarded as statistically significant.

RESULTS

Among 168 SCs, 47 had CRNs (27.9%). Including carcinoma, 15 had an advanced CRN (aCRN) (8.9% aCRN and 0.6% CRC). CRN rate was 35.6% in ≥ 50 years old whereas 22.1% in 40-49 (p = 0.053). aCRN rates (8.4% in 40-49 versus 9.6% in 50-65) were similar (p = 0.792). Metabolic parameters and smoking-drinking history were equally distributed between the groups except FBG and HbA1c as their mean levels were slightly higher in the 50-65 age group (p < 0.05).

CONCLUSIONS

Presented results warrant routine SC in the 40-49-year-old morbidly obese and/or MetS patient population with average risk, and in aged > 50, it certainly must be enforced and included in the preoperative check-list if not done before.

Risks of colorectal advanced neoplasia in young adults versus those of screening colonoscopy in patients aged 50 to 54 years

BACKGROUND AND AIM

The role of screening or diagnostic colonoscopy to detect advanced neoplasia in young cohorts of age < 50 is unclear. This study compared the risk of colorectal neoplasia in a young age cohort against that in 50-54s screening cohort.

METHODS

A multi-center retrospective study was conducted at 14 university hospitals to compare the detection rates of neoplasia and advanced neoplasia in screening or diagnostic colonoscopy in the young cohort of < 50s against those in screening colonoscopy in the 50-54s cohort.

RESULTS

Among 10 477 eligible subjects, 9765 subjects were enrolled after excluding 712 subjects. Advanced neoplasia detection rates in the young screening cohort was significantly lower than that in the 50-54s screening cohort (5.9% vs 9.3%, P < 0.001). Compared with 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 23%, 53%, and 54% in the 45-49s, 40-44s, and 20-39s screening cohorts, respectively. The detection rates of advanced neoplasia in the young diagnostic cohort was 5.0%, which was much lower than 11.8% in 50-54s screening cohort (P < 0.001). Compared with the 50-54s screening cohort, the risk of advanced neoplasia was significantly reduced by 50%, 66%, and 71% in the 45-49s, 40-44s, and 20-39s diagnostic cohorts, respectively.

CONCLUSIONS

Colonoscopy to detect advanced neoplasia in young adults aged < 50 years should be reconsidered as their risk of advanced neoplasia on screening or diagnostic colonoscopy was much lower than those of 50-54s screening cohort; however, colonoscopy screening may be justified for high-risk 45-49s cohorts.

Findings in young adults at colonoscopy from a hospital service database audit

BACKGROUND

Colorectal cancer (CRC) diagnosed at <50 years is predominantly located in the distal colon and rectum. Little is known about which lesion subtypes may serve as CRC precursors in young adults. The aim of this work was to document the prevalence and histological subtype of lesions seen in patients aged <50 years, and any associated clinical features.

METHODS

An audit of the colonoscopy database at The Queen Elizabeth Hospital in Adelaide, South Australia over a 12-month period was undertaken. Findings were recorded from both colonoscopy reports and corresponding histological examination of excised lesions.

RESULTS

Data were extracted from colonoscopies in 2064 patients. Those aged <50 comprised 485 (24%) of the total. CRC precursor lesions (including sessile serrated adenoma/polyps (SSA/P), traditional serrated adenomas, tubular adenomas ≥10 mm or with high-grade dysplasia, and conventional adenomas with villous histology) were seen in 4.3% of patients aged <50 and 12.9% of patients aged ≥50 (P <0.001). Among colonoscopies yielding CRC precursor lesions in patients under 50 years, SSA/P occurred in 52% of procedures (11/21), compared with 27% (55/204) of procedures in patients aged 50 and older (P = 0.02). SSA/P were proximally located in (10/11) 90% of patients aged under 50, and 80% (43/54) of those aged 50 and older (P = 0.46).

CONCLUSIONS

SSA/P were the most frequently observed CRC precursor lesions in patients aged <50. Most CRCs in this age group are known to arise in the distal colon and rectum suggesting that lesions other than SSA/P may serve as the precursor for the majority of early-onset CRC.