Colorectal cancer incidence, mortality, and stage distribution in European countries in the colorectal cancer screening era: an international population-based study

The Insulin-like Growth Factor System and Colorectal Cancer

Insulin-like growth factors (IGFs) are peptides which exert mitogenic, endocrine and cytokine activities. Together with their receptors, binding proteins and associated molecules, they participate in numerous pathophysiological processes, including cancer development. Colorectal cancer (CRC) is a disease with high incidence and mortality rates worldwide, whose etiology usually represents a combination of the environmental and genetic factors. IGFs are most often increased in CRC, enabling excessive autocrine/paracrine stimulation of the cell growth. Overexpression or increased activation/accessibility of IGF receptors is a coinciding step which transmits IGF-related signals. A number of molecules and biochemical mechanisms exert modulatory effects shaping the final outcome of the IGF-stimulated processes, frequently leading to neoplastic transformation in the case of irreparable disbalance. The IGF system and related molecules and pathways which participate in the development of CRC are the focus of this review.

IGFBP5 is Upregulated and Associated with Poor Prognosis in Colorectal Cancer

Purpose

This study aimed to investigate the role of IGFBP5 in colorectal cancer (CRC) and the relationship between the expression of IGFBP5 and clinicopathological parameters in CRC patients.

Patients and Methods

Immunohistochemical analysis was used to detect the expression of IGFBP5 and its correlation with clinicopathological parameters of CRC patients. Prognosis analysis, gene set enrichment analysis, and protein interaction network analysis were performed using bioinformatics analysis. The Genomics of Drug Sensitivity in Cancer (GDSC) dataset was used to analyze the correlation between the expression of IGFBP5 and drug resistance.

Results

Immunohistochemical analysis revealed that the expression of IGFBP5 was significantly higher in CRC tissues than in para-cancerous tissues (P < 0.05). High expression of IGFBP5 was associated with tumor differentiation and the N stage of CRC (P < 0.05). Moreover, high expression of IGFBP5 predicted worse overall survival and disease-free survival in CRC patients (P < 0.05). The expression of IGFBP5 was associated with cell–matrix adhesion, extracellular matrix binding, and collagen binding (P < 0.05). Furthermore, IGFBP5 was involved in the Hedgehog signaling pathway and PI3K-Akt signaling pathway (P < 0.05). IGF1, IGF2, SPP1, LTBP1, and FAM20C were most closely related to IGFBP5.

Conclusion

The expression of IGFBP5 is upregulated and associated with tumor differentiation, lymph node metastasis, drug resistance, and prognosis in CRC patients.

Proportion and stage distribution of screen-detected and non-screen-detected colorectal cancer in nine European countries: an international, population-based study

BACKGROUND

The effects of recently implemented colorectal cancer screening programmes in Europe on colorectal cancer mortality will take several years to be fully known. We aimed to analyse the characteristics and parameters of screening programmes, proportions of colorectal cancers detected through screening, and stage distribution in screen-detected and non-screen-detected colorectal cancers to provide a timely assessment of the potential effects of screening programmes in several European countries.

METHODS

We conducted this population-based study in nine European countries for which data on mode of detection were available (Belgium, Denmark, England, France, Italy, Ireland, the Netherlands, Slovenia, and Spain). Data from 16 population-based cancer registries were included. Patients were included if they were diagnosed with colorectal cancer from the year that organised colorectal cancer screening programmes were implemented in each country until the latest year with available data at the time of analysis, and if their age at diagnosis fell within the age groups targeted by the programmes. Data collected included sex, age at diagnosis, date of diagnosis, topography, morphology, clinical and pathological TNM information based on the edition in place at time of diagnosis, and mode of detection (ie, screen detected or non-screen detected). If stage information was not available, patients were not included in stage-specific analyses. The primary outcome was proportion and stage distribution of screen-detected versus non-screen detected colorectal cancers.

FINDINGS

228 667 colorectal cancer cases were included in the analyses. Proportions of screen-detected cancers varied widely across countries and regions. The highest proportions (40-60%) were found in Slovenia and the Basque Country in Spain, where FIT-based programmes were fully rolled out, and participation rates were higher than 50%. A similar proportion of screen-detected cancers was also found for the Netherlands in 2015, where participation was over 70%, even though the programme had not yet been fully rolled out to all age groups. In most other countries and regions, proportions of screen-detected cancers were below 30%. Compared with non-screen-detected cancers, screen-detected cancers were much more often found in the distal colon (range 34·5-51·1% screen detected vs 26·4-35·7% non-screen detected) and less often in the proximal colon (19·5-29·9% screen detected vs 24·9-32·8% non-screen detected) p≤0·02 for each country, more often at stage I (35·7-52·7% screen detected vs 13·2-24·9% non-screen detected), and less often at stage IV (5·8-12·5% screen detected vs 22·5-31·9% non-screen detected) p<0·0001 for each country.

INTERPRETATION

The proportion of colorectal cancer cases detected by screening varied widely between countries. However, in all countries, screen-detected cancers had a more favourable stage distribution than cancers detected otherwise. There is still much need and scope for improving early detection of cancer across all segments of the colorectum, and particularly in the proximal colon and rectum.

FUNDING

Deutsche Krebshilfe.

Study of Correlation between Intestinal Microbiota and Traditional Chinese Medicine Syndrome of Patients with Colon Cancer

Objective

This research aims to study the material basis of the formation and specific bacteria of traditional Chinese medicine (TCM) syndrome from the characteristics of the intestinal microbiota of patients with colon cancer (CC) before and after the operation.

Methods

A cross-sectional study was conducted on 84 patients with CC and 24 healthy controls. A total of 168 and 24 stool samples were collected from CC patients before and after the operation and healthy controls. DNA was extracted from 192 stool samples and then amplified using PCR. The V3-V4 high variable areas were analyzed by 16s rDNA sequencing.

Results

The community diversity, in descending order, was the healthy control group and postoperative and preoperative groups of CC patients. The abundance of beneficial bacteria was postoperative group of CC patients > healthy control group > preoperative group of CC patients. Among the comparisons of the intestinal microbiota of preoperative groups of CC patients with different TCM syndromes, the community diversity in descending order was damp heat accumulation (DHA), spleen deficiency and dampness (SDD), spleen and kidney yang deficiency (SKYD), liver and kidney yin deficiency (LKYD), and deficiency of qi and blood (QBD), respectively. Specific microbiome analysis showed that the differences in the abundance of 42 taxons were statistically significant among the preoperative groups of CC patients with the five TCM syndromes and the healthy control group. While comparing the intestinal microbiota of postoperative groups with the five TCM syndromes, the community diversity in descending order is DHA, SDD, LKYD, SKYD, and QBD. Specific microbiome analysis showed that the differences in the abundance of 46 taxons were statistically significant among the postoperative groups of CC patients with the five TCM syndromes and the healthy control group. Streptococcus and Streptococcus mutans showed no statistical significance between the preoperative group and postoperative groups of CC with DHA syndrome (P > 0.05). Bacteroides at phylum and genus levels showed that there was no statistical significance between the preoperative group and the postoperative group of CC with SKYD syndrome (P > 0.05).

Conclusions

Before and after surgery, with the deterioration of TCM syndrome: DHA ⟶ SDD ⟶ SKYD ⟶ LKYD ⟶ QBD, the number of beneficial bacteria in CC patients' intestines decreased while the number of pathogenic bacteria increased, and the community structure of intestinal microbiota tends to be unitized, indicating a serious intestinal microbiological disorder. After radical surgery and perioperative intervention, the intestinal microbiota diversity and community structure of postoperative CC patients were closer to those of healthy people than preoperative. However, they were still imbalanced. The intestinal microbiota of CC patients with different TCM syndromes differs significantly, which is important for understanding the pathogenesis of CC in TCM. The DHA and SKYD syndromes in CC patients before and after surgery showed significant differences in the microbial structure. Streptococcus and Streptococcus mutans were the specific species with a significant difference in CC patients with DHA syndrome, while bacteroides were the specific species in CC patients with SKYD syndrome.

Chemotherapy-induced functional brain abnormality in colorectal cancer patients: a resting‐state functional magnetic resonance imaging study

Introduction

Chemotherapy-induced cognitive impairment (i.e., “chemobrain”) is a common neurotoxic side-effect experienced by many cancer survivors who undergone chemotherapy. However, the central mechanism underlying chemotherapy-related cognitive impairment is still unclear. The purpose of this study was to investigate the changes of intrinsic brain activity and their associations with cognitive impairment in colorectal cancer (CRC) patients after chemotherapy.

Methods

Resting‐state functional magnetic resonance imaging data of 29 CRC patients following chemotherapy and 29 matched healthy controls (HCs) were collected in this study, as well as cognitive test data including Mini Mental State Exam (MMSE), Montreal Cognitive Assessment (MoCA) and Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog). The measure of fractional amplitude of low-frequency fluctuation (fALFF) was calculated and compared between groups. The correlations between the fALFF of impaired brain region and cognitive performance were also analyzed.

Results

Compared with HCs, CRC patients following chemotherapy showed decreased fALFF values in the left anterior cingulate gyrus (ACG) and middle frontal gyrus, as well as increased fALFF values in the left superior frontal gyrus (orbital part) and middle occipital gyrus. Moreover, positive associations were identified between fALFF values of the left ACG and the total scores of MMSE, MoCA and FACT-Cog in the patient group.

Conclusion

These findings indicated that CRC patients after chemotherapy had decreased intrinsic brain activity in the left ACG, which might be vulnerable to the neurotoxic side-effect of chemotherapeutic drugs and related to chemotherapy-induced cognitive impairment.

NK Cells and Other Cytotoxic Innate Lymphocytes in Colorectal Cancer Progression and Metastasis

Colorectal cancer (CRC) is one of the most common malignancies and leading causes of cancer-related deaths worldwide. Despite its complex pathogenesis and progression, CRC represents a well-fitting example of how the immune contexture can dictate the disease outcome. The presence of cytotoxic lymphocytes, both CD8⁺ T cells and natural killer (NK) cells, represents a relevant prognostic factor in CRC and is associated with a better overall survival. Together with NK cells, other innate lymphocytes, namely, innate lymphoid cells (ILCs), have been found both in biopsies of CRC patients and in murine models of intestinal cancer, playing both pro- and anti-tumor activities. In particular, several type 1 innate lymphoid cells (ILC1) with cytotoxic functions have been recently described, and evidence in mice shows a role for both NK cells and ILC1 in controlling CRC metastasis. In this review, we provide an overview of the features of NK cells and the expanding spectrum of innate lymphocytes with cytotoxic functions. We also comment on both the described and the potential roles these innate lymphocytes can play during the progression of intestinal cancer leading to metastasis. Finally, we discuss recent advances in the molecular mechanisms underlying the functional regulation of cytotoxic innate lymphocytes in CRC.

Chinese and Global Burdens of Gastrointestinal Cancers From 1990 to 2019

Background

Gastrointestinal (GI) cancers are an important component of the tumor. This study aimed to investigate the burden of six major GI cancers in China and globally from 1990 to 2019.

Methods

We conducted a cross-sectional study based on the Global Burden of Disease Study (GBD) 2019. Indicators on incidence, deaths, disability-adjusted life-years (DALYs), and risk factors for esophageal, stomach, liver, pancreatic, colon and rectum, and gallbladder and biliary tract cancers were collected and analyzed for time trends. The contribution of each cancer and the proportion of cases in China among global cases were further reported.

Results

Global incidence cases, death cases, and DALYs of GI cancers showed an overall ascending trend over the past 30 years, but there was temporal and geographical variation across cancer types. By 2019, colon and rectum cancer had overtaken stomach cancer as the most burdensome GI cancer globally. However, stomach cancer narrowly continued to be the most burdensome GI in China. In addition, the proportion of incidence and death cases of stomach, pancreatic, colon and rectum, and gallbladder and biliary tract cancers among global cases had further increased. It was noteworthy that the burden of liver cancer in China has been alleviated significantly.

Conclusion

GI cancers remain a major public health problem in China and globally. Despite the temporal and geographic diversity of different cancers, targeted primary and secondary prevention are still necessary for the future to face these unknown challenges.

Survival trends in patients diagnosed with colon and rectal cancer in the nordic countries 1990-2016: The NORDCAN survival studies

BACKGROUND

Survival of patients with colon and rectal cancer has improved in all Nordic countries during the past decades. The aim of this study was to further assess survival trends in patients with colon and rectal cancer in the Nordic countries by age at diagnosis and to present additional survival measures.

METHODS

Data on colon and rectal cancer cases diagnosed in the Nordic countries between 1990 and 2016 were obtained from the NORDCAN database. Relative survival was estimated using flexible parametric models. Both age-standardized and age-specific measures for women and men were estimated from the models, as well as reference-adjusted crude probabilities of death and life-years lost.

RESULTS

The five-year age-standardized relative survival of colon and rectal cancer patients continued to improve for women and men in all Nordic countries, from around 50% in 1990 to about 70% at the end of the study period. In general, survival was similar across age and sex. The largest improvement was seen for Danish men and women with rectal cancer, from 41% to 69% and from 43% to 71%, respectively. The age-standardized and reference-adjusted five-year crude probability of death in colon cancer ranged from 30% to 36% across countries, and for rectal cancer from 20% to 33%. The average number of age-standardized and reference-adjusted life-years lost ranged between six and nine years.

CONCLUSION

There were substantial improvements in colon and rectal cancer survival in all Nordic countries 1990-2016. Of special note is that the previously observed survival disadvantage in Denmark is no longer present.

Young-Onset Colorectal Cancer in Serbia: Tertiary Cancer Center Experience

Purpose: Early-onset colorectal cancer (CRC) is a growing problem. The aim of the study was to identify adolescent and young adult (AYA) patients with CRC in Serbia, treated in the single tertiary cancer center. Materials and Methods: This is a retrospective study that included only AYA patients (ages 18-39 years) with histologically confirmed CRC. In 11 year (2009-2019), 109 patients were identified from a single-institution database and their clinical variables and outcomes were analyzed. Results: The prevalence of a positive family history of CRC was 12.8%. Presenting symptoms were not different than traditional CRC. More than a quarter were diagnosed as an emergency. Left-sided tumors were diagnosed in 83.4% and mucinous tumors were recorded in one-third of the patients. Postoperatively patients mainly were in PS0-1 (97%). Patients presented as stages II (18.3%), III (47.7%), and IV (33.9%). The recurrence rate in local stages was 50%. Surgical treatment of localized metastatic disease was performed in almost half of the stage IV patients. Median disease-free survival for patients with the recurrent disease was 11.8 months. Median overall survival (OS) for the local and metastatic stage was 64.3 and 20.5 months, respectively. Survival analysis showed that performance status, bowel obstruction, N2 status, local invasions, disease stage, and surgery in stage IV had a statistically significant influence on OS. Conclusion: Serbian AYA CRC patients are of good general condition, with advanced left-sided tumors, common mucinous histology, and inverse histology features. Surgery in metastatic disease provided long-term survival. The outcome of the patient is influenced by a late diagnosis, inverse histological features, and treatment provided.

The Incidence-Based Mortality and Survival Trends in Patients with Gastric Signet Ring Cell Carcinoma

Background and Aim. Gastric signet ring cell carcinoma (SRC) is a distinct subtype of gastric cancer. This study aims to analyze the incidence-based mortality and survival trends in patients with gastric SRC over the past decades. Materials and Methods. The patients from the Surveillance, Epidemiology, and End Results (SEER) database were recruited to explore the incidence-based mortality and survival trends from 2000 to 2017. We further analyzed the differences in mortality and survival trends in these patients by sex and stage. We also used joinpoint software to evaluate the trends in annual percentage change (APC) for statistical significance. Results. 14916 patients were collected, including 7801 (52.3%) male and 7115 (47.7%) female. We identified a single joinpoint at 2002. The overall incidence-based mortality of gastric SRC declined in America after 2002 (APC = −1.21, $P<0.05$ ). In stratified analysis by sex and stage, the incidence-based mortality rate was higher in males than females. After 2002, the mortality rate decreased significantly in male (APC = −1.68, $P<0.05$ ) and M0-stage patients (APC = −1.75, $P<0.05$ ). In survival trend analysis, the 2-year relative survival improved in M0-stage gastric SRC, especially for males (APC = 1.14, $P<0.05$ ). As for M1-stage patients, the 2-year relative survival significantly elevated in both male (APC = 3.87, $P<0.05$ ) and female (APC = 5.63, $P<0.05$ ) patients. Conclusions. The incidence-based mortality of gastric SRC has declined, and survival has improved in America over time. These optimistic trends may be attributed to cancer screening implementation and advances in novel treatments in the past decades.

Immune Response in Vitamin D Deficient Metastatic Colorectal Cancer Patients: A Player That Should Be Considered for Targeted Vitamin D Supplementation

Background: Vitamin D deficiency is a poor prognostic factor in metastatic colorectal cancer (mCRC); however, targeted supplementation trials have so far yielded limited results. We investigated clinical-laboratory parameters influencing vitamin D deficiency, with a particular focus on immune response, and the effect on survival. These parameters could help optimize targeted supplementation therapy. Methods: Association of plasma 25-hydroxyvitamin D (25(OH])D) with overall survival (OS) was assessed with the Hazard Ratio Smoothed Curve with Restricted Cubic Splines (HRSC-RCS) and maximally selected rank statistics (MSRS) in mCRC patients who underwent first-line chemotherapy. Several hematobiochemical variables were evaluated as predictors of vitamin D deficiency by means of Least Absolute Shrinkage and Selection Operator (LASSO) analysis. In a patient subset, peripheral lymphocyte subpopulations were also analyzed. Results: One hundred thirty-three mCRC patients were included. The median(m) baseline 25(OH)D was 10.8 ng/mL (range 3−53.4). HRSC-RCS revealed a linear association between 25(OH)D and OS. MSRS found 10 ng/mL as the optimal 25(OH)D cut-off. The median OS for 25(OH)D < 10 (n = 60) vs. > 10 ng/mL (n = 73) was 12.3 and 24.5 months, respectively (p = 0.002). The LASSO analysis identified high neutrophil-to-lymphocyte ratio (NLR > 3.5) as the strongest predictor of vitamin D deficiency (Odds Ratio 3.35, p 0.0009). Moreover, patients with low 25(OH)D levels (< 10 ng/mL) and high NLR (>3.5) had the shortest survival and patients with 25(OH)D >10 ng/mL and NLR <3.5 had the longest: mOS 8.1 and 28.1 months, respectively, HR 3.40 (1.76−6.59), p 0.0004. Besides the significant difference in NLR between 25(OH)D < and > 10 ng/mL patients (mNLR 3.6 vs. 2.9, p 0.03), the lymphocyte subpopulation analysis revealed that vitamin D deficiency was associated with high T- CD4+ (p = 0.04) and low B (p = 0.03) lymphocyte frequency. Conclusions: NLR is a powerful predictor of Vitamin D deficiency and can further help in stratifying prognosis. Vitamin D deficiency was associated with significant variations in peripheral immune cells. We hypothesize that integrated targeted interventions to both vitamin D and immune system would improve the prognosis of mCRC patients.

A comparative examination of colorectal cancer burden in European Union, 1990-2019: Estimates from Global Burden of Disease 2019 Study

AIM

This study examines the burden of colorectal cancer (CRC) in European Union (EU) countries in the last 3 decades.

METHODS

The data pertaining to CRC burden were procured from the Global Burden of Disease 2019 Study for 28 EU countries (including United Kingdom) for the period 1990-2019. The age-standardized rates of CRC were utilized to compare the country-wise burden and joinpoint regression models were applied to examine the trends.

RESULTS

In EU, CRC incident cases increased by 70.2% from 261,306 to 444,872 and deaths increased by 36.8% from 155,823 to 213,174 between 1990 and 2019. The age-standardized incidence rate (ASIR) increased by 11.9% from 37.8/100,000 to 42.3/100,000 between 1990 and 2019; in contrast, the age-standardized mortality rate (ASMR) decreased by 16.9% (1990: 22.4/100,000; 2019: 18.6/100,000) and age-standardized DALYs rate (ASDALR) decreased by 18.6% (1990: 472.9/100,000; 2019: 385.1/100,000) in the study period. In 2019, Hungary was the leading country in terms of ASMR (28.6/100,000) and ASDALR (630.3/100,000), and Lithuania (29.2/100,000) had the lowest ASIR, whereas Finland had the lowest ASMR (12.3/100,000) and ASDALR (253.6/100,000) in 2019.

CONCLUSION

CRC incidence is increasing in EU and mortality rates, although decreasing, are still unacceptably high. CRC control efforts must be focused around early detection using screening and prevention through reduction of modifiable risk factors. Increasing CRC incidence rates in young adults in recent years requires more research to pinpoint risk factors, and there must be more awareness of this recent development among general public and clinicians.

One or two faecal immunochemical tests in an organised population-based colorectal cancer screening programme in Murcia (Spain)

OBJECTIVE

Roll-out of population-based colorectal cancer (CRC) screening with faecal immunochemical test (FIT) is limited by availability of further investigations, particularly colonoscopy and examination of excised lesions. Our objective was to assess whether variation in number of faecal samples and threshold adjustment can optimise resource utilisation and CRC detection rate.

METHODS

Three different screening strategies were compared for the same FIT threshold using a quantitative FIT system: one FIT, positive when >20 µg Hb/g faeces; two FIT, positive when either was >20 µg Hb/g faeces; and two FIT, positive when the mean was >20 µg Hb/g faeces. We calculated changes in the size of population the provider could invite to screening for an equal number of screening positive results, and CRC and adenoma detected.

RESULTS

In our setting, Region of Murcia, south of Spain (not fully rolled out screening programme), changing the usual strategy of two FIT, positive when either to positive when the mean was >20 µg Hb/g faeces, would increase population invited by 37.81% with the same number of positive results (which would generate a CRC detection rate of 19.2%). In a fully rolled out programme, changing the strategy from one to two FIT (positive when the mean is >20 µg Hb/g faeces), would increase CRC detection rate by 4.64% with an increase of only 13.34% in positive FIT.

CONCLUSIONS

In a population-based CRC screening programme, smart use of number of FITs and positivity threshold can increase population invited and CRC detection without increasing the number of colonoscopies and pathological examinations needed.

Colorectal Cancer Diagnosis: The Obstacles We Face in Determining a Non-Invasive Test and Current Advances in Biomarker Detection

Simple Summary

Colorectal cancer (CRC) is one of the most common cancers in the western world. CRC originates from precursor adenomatous polyps, which may over time develop into cancer. Endoscopic evaluation remains the gold-standard investigation for the disease. In the absence of molecular tools for early detection, the removal of neoplastic adenomas via polypectomy remains an important measure to prevent dysplastic adenomas from evolving into invasive carcinoma. Colonoscopy is an intrusive procedure that provides an uncomfortable experience for patients. Kits for testing for the presence of blood hemoglobin in the stool are now widely used, and DNA methylation-based detection kits have been approved in the USA for testing the stool and plasma, but few other molecular biomarkers have found their way into medical practice. This review summarizes current trends in the detection and screening of CRC and provides a definitive review of emerging molecular biomarkers for CRC.

Abstract

Globally, colorectal cancer (CRC) is the third most common cancer, with 1.4 million new cases and over 700,000 deaths per annum. Despite being one of the most common cancers, few molecular approaches to detect CRC exist. Carcinoembryonic antigen (CEA) is a known serum biomarker that is used in CRC for monitoring disease recurrence or response to treatment. However, it can also be raised in multiple benign conditions, thus having no value in early detection or screening for CRC. Molecular biomarkers play an ever-increasing role in the diagnosis, prognosis, and outcome prediction of disease, however, only a limited number of biomarkers are available and none are suitable for early detection and screening of CRC. A PCR-based Epi proColon^® blood plasma test for the detection of methylated SEPT9 has been approved by the USFDA for CRC screening in the USA, alongside a stool test for methylated DNA from CRC cells. However, these are reserved for patients who decline traditional screening methods. There remains an urgent need for the development of non-invasive molecular biomarkers that are highly specific and sensitive to CRC and that can be used routinely for early detection and screening. A molecular approach to the discovery of CRC biomarkers focuses on the analysis of the transcriptome of cancer cells to identify differentially expressed genes and proteins. A systematic search of the literature yielded over 100 differentially expressed CRC molecular markers, of which the vast majority are overexpressed in CRC. In terms of function, they largely belong to biological pathways involved in cell division, regulation of gene expression, or cell proliferation, to name a few. This review evaluates the current methods used for CRC screening, current availability of biomarkers, and new advances within the field of biomarker detection for screening and early diagnosis of CRC.

Determining Which Patients Require Preoperative Pelvic Radiotherapy Before Curative-Intent Surgery and/or Ablation for Metastatic Rectal Cancer

BACKGROUND

The aim of this study is to determine the optimal indications for preoperative pelvic radiotherapy (RT) in patients with metastatic rectal cancer who underwent curative-intent surgical resection and/or ablation.

METHODS

Between January 2000 and October 2019, 246 patients who met our inclusion criteria were enrolled. Preoperative RT was performed in 22 patients (8.9%). Lower margin below the peritoneal reflection (p < 0.001), mesorectal fascia (MRF) invasion (p = 0.02), and lateral pelvic lymph node (LPLN) involvement (p = 0.005) were more frequent in the preoperative RT group.

RESULTS

During the median follow-up period of 13.3 months (interquartile range [IQR]: 6.0-36.3 months), local recurrence (LR) was identified in 60 patients (24.4%). It was the first site of recurrence in 45 of them (18.3%). Among them, three patients were in the preoperative RT group. On multivariable analysis, lower margin below the peritoneal reflection, MRF invasion, LPLN involvement, carcinoembryonic antigen (CEA) level ≥ 10 ng/mL before treatment, and preoperative RT were significant prognostic factors for LR-free survival (LRFS). In the patient group without any risk factors, the 2-year LRFS rate was 94.9% without preoperative RT. In the patient group with one or more risk factors, the 2-year LRFS was 64.4% without and 95.2% with preoperative RT.

CONCLUSION

LR developed in about 25% of patients within 2 years. Preoperative RT should be considered, especially in patients with a risk factor for LR, including lower margin below the peritoneal reflection, MRF invasion, LPLN involvement, or CEA ≥ 10 ng/mL before treatment.

Comparison of the colonic J-pouch versus straight (end-to-end) anastomosis following low anterior resection: a systematic review and meta-analysis

AIMS

To evaluate comparative outcomes of straight (end-to-end) anastomosis versus colonic J-pouch anastomosis following anterior resection.

METHODS

A systematic search of multiple electronic data sources was conducted, and all studies comparing straight (end-to-end) anastomosis versus J-pouch anastomosis were included. Anastomotic complications, post-operative complications, re-operation, mortality, and functional outcomes were the evaluated outcome parameters. Revman 5.3 was used for data analysis.

RESULTS

Twenty-seven studies reporting a total number of 3293 patients who underwent straight anastomosis (n = 1581) or J-pouch (n = 1712) were included. Anastomotic leak and re-operation rates were significantly higher in the straight group compared to the J-pouch group [RD 0.03, P = 0.03] and [OR 1.87, P = 0.003], respectively. Stool frequency per 24 h at 6 months and 12 months was lower in the J-pouch group than the straight group [MD 2.13, P = 0.003] and [MD 1.44, P = 0.00001], respectively. In addition, the use of anti-diarrheal medication is lower at 12 months in the J-pouch group [MD 3.85, P = 0.03]. Moreover, the two groups showed comparable results regarding SSI, sepsis, paralytic ileus, anastomotic stricture formation, anastomotic bleeding, and mortality.

CONCLUSION

J-pouch anastomosis showed lower risk for anastomotic leak and re-operation. Furthermore, better functional outcomes such as stool frequency were achieved using the colonic J-pouch reconstruction over the conventional straight end-to-end anastomosis.

Using fecal immunochemical test values below conventional cut-off to individualize colorectal cancer screening

Background and study aims  Of the participants in the Danish screening program, 89.9 % to 92.5 % have fecal immunochemical test (FIT) values < 10 μg/g feces (equivalent to 50 ng hemoglobin/mL buffer). This study aimed to investigate the risk of interval colorectal cancer (CRC) in this group before the next biennial screening round. Patients and methods  This cohort study included all citizens from the region of Southern Denmark who participated in the Danish bowel screening program from 2014 trough 2016 and had a FIT value < 10 μg/g feces. Individuals receiving a CRC diagnosis were identified through the national CRC registry, with a follow up of 2 years corresponding to the current screening interval. We also examined the 3-year CRC incidence. Hazard ratios (HRs) were estimated using univariate and multivariate Cox proportional hazard regression models. Results  Data from 185,654 citizens presenting with a FIT value < 10 μg/g feces were eligible for analysis. Overall, interval CRC incidence was 0.07 % within 2 years with HRs of 4.16 (95 % confidence interval [CI] 2.67;6.48) and 5.8 (95 % CI 3.34;10.05) for FIT values of 4 to 6.9 μg/g feces and 7 to 9.9 μg/g feces, respectively, compared to those having a FIT value below the limit of quantification of 4 μg/g feces. After 3 years, the overall CRC incidence increased to 0.14 %; however, this was not significant. Conclusions  This study demonstrates a positive correlation between FIT value and risk of interval cancer even for very low values. It further suggests that an increase in the screening interval could be reasonable in the low FIT categories.

Weakly supervised end-to-end artificial intelligence in gastrointestinal endoscopy

Artificial intelligence (AI) is widely used to analyze gastrointestinal (GI) endoscopy image data. AI has led to several clinically approved algorithms for polyp detection, but application of AI beyond this specific task is limited by the high cost of manual annotations. Here, we show that a weakly supervised AI can be trained on data from a clinical routine database to learn visual patterns of GI diseases without any manual labeling or annotation. We trained a deep neural network on a dataset of N = 29,506 gastroscopy and N = 18,942 colonoscopy examinations from a large endoscopy unit serving patients in Germany, the Netherlands and Belgium, using only routine diagnosis data for the 42 most common diseases. Despite a high data heterogeneity, the AI system reached a high performance for diagnosis of multiple diseases, including inflammatory, degenerative, infectious and neoplastic diseases. Specifically, a cross-validated area under the receiver operating curve (AUROC) of above 0.70 was reached for 13 diseases, and an AUROC of above 0.80 was reached for two diseases in the primary data set. In an external validation set including six disease categories, the AI system was able to significantly predict the presence of diverticulosis, candidiasis, colon and rectal cancer with AUROCs above 0.76. Reverse engineering the predictions demonstrated that plausible patterns were learned on the level of images and within images and potential confounders were identified. In summary, our study demonstrates the potential of weakly supervised AI to generate high-performing classifiers and identify clinically relevant visual patterns based on non-annotated routine image data in GI endoscopy and potentially other clinical imaging modalities.

Aspirin Colorectal Cancer Prevention in Lynch Syndrome: Recommendations in the Era of Precision Medicine

Cancer prevention in the era of precision medicine has to consider integrated therapeutic approaches. Therapeutic cancer prevention should be offered to selected cohorts with increased cancer risk. Undoubtedly, carriers of hereditary cancer syndromes have a well-defined high cancer risk. Lynch Syndrome is one of the most frequent hereditary syndromes; it is mainly associated with colorectal cancer (CRC). Nonsteroidal anti-inflammatory drugs and, in particular, aspirin use, has been associated with reduced CRC risk in several studies, initially with contradictory results; however, longer follow-up confirmed a reduced CRC incidence and mortality. The CAPP2 study recruited 861 Lynch syndrome participants randomly assigned to 600 mg of aspirin versus placebo. Like sporadic CRCs, a significant CRC risk reduction was seen after an extended follow-up, with a median treatment time that was relatively short (2 years). The ongoing CAPP3 will address whether lower doses are equally effective. Based on pharmacology and clinical data on sporadic CRCs, the preventive effect should also be obtained with low-dose aspirin. The leading international guidelines suggest discussing with Lynch syndrome carriers the possibility of using low-dose aspirin for CRC prevention. We aim systematically promote this intervention with all Lynch syndrome carriers.

Survival Trends of Right- and Left-Sided Colon Cancer across Four Decades: A Norwegian Population-Based Study

BACKGROUND

Patients with right-sided colon cancer (RCC) and left-sided colon cancer (LCC) differ clinically and molecularly. The main objective was to investigate stage-stratified survival and recurrence of RCC and LCC across four 10-year periods.

METHODS

Patients diagnosed from 1977 to 2016 with colon adenocarcinoma were included from the Cancer Registry of Norway. Primary tumor location (PTL) was defined as RCC if proximal and LCC if distal to the splenic flexure. Multivariable regressions were used to estimate HRs for overall survival (OS), recurrence-free survival (RFS), survival after recurrence (SAR), and excess HRs (eHR) for relative survival (RS).

RESULTS

72,224 patients were eligible for analyses [55.1% (n = 39,769/72,224) had RCC]. In 1977 to 1986, there was no difference between LCC and RCC in OS [HR, 1.01; 95% confidence interval (CI), 0.97-1.06; P = 0.581] or RS (eHR, 0.96; 95% CI, 0.90-1.02; P = 0.179). In 2007 to 2016, LCC had significantly better OS (HR, 0.84; 95% CI, 0.80-0.87; P < 0.001) and RS (eHR, 0.76; 95% CI, 0.72-0.81; P < 0.001) compared with RCC. The gradually diverging and significantly favorable prognosis for LCC was evident for distant disease across all time periods and for regional disease from 2007 onward. There was no difference in RFS between LCC and RCC in patients less than 75 years during 2007 to 2016 (HR, 0.99; 95% CI, 0.91-1.08; P = 0.819); however, SAR was significantly better for LCC (HR, 0.61; 95% CI, 0.53-0.71; P < 0.001).

CONCLUSIONS

A gradually diverging and increasingly favorable prognosis was observed for patients with LCC with advanced disease over the past four decades.

IMPACT

Current PTL survival disparities stress the need for further exploring targetable molecular subgroups across and within different PTLs to further improve patient outcomes.

MicroRNA-656-3p inhibits colorectal cancer cell migration, invasion, and chemo-resistance by targeting sphingosine-1-phosphate phosphatase 1

Colorectal cancer presents high rates of recurrence and metastasis, and the occurrence and progression and mechanism of its invasion and metastasis are not fully understood. The expression of miR-656-3p in patient samples and 10 cell lines were measured. Bioinformatic databases were used to predict miRNAs. Protein expressions were examined using Western blot. Transwell assay was used to measure cell migration and invasion. Transplanted tumor model in nude mice was established. Removal of the miR-656-3p by specific knocking-down of this gene promoted the chemo-resistance of colorectal cancer cells. Critically, we identified sphingosine-1-phosphate phosphatase 1 (SGPP1) as a downsteam target of the miR-656-3p, which we first obtained from 199 potential target genes from Targetscan, 200 genes from miRDB and 200 genes from DIANA, respectively. Then, we identified the interaction between SGPP1 and the miR-656-3p on 3’ UTR of SGPP1 gene. Knockdown of SGPP1 greatly suppressed the tumor growth in vivo and epithelial mesenchymal transition process. miR-656-3p could regulate cell proliferation and chemoresistance in the colorectal cancer that associate to downstream target with SGPP1. Along with its downstream molecule, we would like to predict that the SGPP1 associated miR-656-3p could be used to develop early for early diagnostics for CRC oncogenesis.

Odds of Incomplete Colonoscopy in Colorectal Cancer Screening Based on Socioeconomic Status

The aim of this study is to investigate the association between socioeconomic status (SES) and the risk of having an incomplete colonoscopy (IC) in the Danish Colorectal Cancer (CRC) Screening Program. In this register-based study we included 71,973 participants who underwent colonoscopy after a positive fecal immunochemical test in the Danish CRC Screening Program. The main exposure, SES, was defined by income and education, and the outcome by complete or incomplete colonoscopy. Among the participants, 5428 (7.5%) had an incomplete colonoscopy. The odds ratio (OR) for ICs due to inadequate bowel preparation was 1.67 (95% CI: 1.46; 1.91) for income in the 1 quartile compared to income in the 4th quartile. ORs for income in the 2nd quartile was 1.38 (95% CI: 1.21; 1.56) and 1.17 (95% CI: 1.03; 1.33) for income in the 3rd quartile. For the educational level, an association was seen for high school/vocational education with an OR of 0.87 (95% CI: 0.79; 0.97) compared to higher education. For ICs due to other reasons, the level of income was associated with the risk of having an IC with an OR of 1.19 (95% CI: 1.05; 1.35) in the 1st quartile and an OR of 1.19 (95% CI: 1.06; 1.34) in the 2nd quartile. For the educational level, there were no significant associations. Low income is associated with high risk of having an IC, whereas educational level does not show the same unambiguous association.

Colorectal Cancer Screening within Colonoscopy Capacity Constraints: Can FIT-Based Programs Save More Lives by Trading off More Sensitive Test Cutoffs against Longer Screening Intervals?

Introduction. Colorectal cancer (CRC) prevention programs using fecal immunochemical testing (FIT) in screening rely on colonoscopy for secondary and surveillance testing. Colonoscopy capacity is an important constraint. Some European programs lack sufficient capacity to provide optimal screening intensity regarding age ranges, intervals, and FIT cutoffs. It is currently unclear how to optimize programs within colonoscopy capacity constraints. Design. Microsimulation modeling, using the MISCAN-Colon model, was used to determine if more effective CRC screening programs can be identified within constrained colonoscopy capacity. A total of 525 strategies were modeled and compared, varying 3 key screening parameters: screening intervals, age ranges, and FIT cutoffs, including previously unevaluated 4- and 5-year screening intervals (using a lifetime horizon and 100% adherence). Results were compared with the policy decisions taken in Ireland to provide CRC screening within available colonoscopy capacity. Outcomes estimated net costs, quality-adjusted life-years (QALYs), and required colonoscopies. The optimal strategies within finite colonoscopy capacity constraints were identified. Results. Combining a reduced FIT cutoff of 10 µg Hb/g, an extended screening interval of 4 y and an age range of 60–72 y requires 6% fewer colonoscopies, reduces net costs by 23% while preventing 15% more CRC deaths and saving 16% more QALYs relative to a strategy (FIT 40 µg Hb/g, 2-yearly, 60–70 year) approximating current policy. Conclusion. Previously overlooked longer screening intervals may optimize cancer prevention with finite colonoscopy capacity constraints. Changes could save lives, reduce costs, and relieve colonoscopy capacity pressures. These findings are relevant to CRC screening programs across Europe that employ FIT-based testing, which face colonoscopy capacity constraints.

Impact of COVID-19 and suspension of colorectal cancer screening on incidence and stage distribution of colorectal cancers in the Netherlands

Many countries had to suspend their colorectal cancer (CRC) screening programme as a result of the COVID-19 pandemic. This eventually may lead to postponed diagnoses of premalignant lesions and CRC, resulting in increased incidence or more advanced CRCs rates. This study aimed to assess the impact of the COVID-19 pandemic on incidence and stage distribution of CRCs in the Netherlands, by monitoring CRC diagnoses and stage distribution in the months before, during and after the first COVID-19 wave. Data on incidence and stage distribution of CRCs of individuals aged 55-75 years in 25 hospitals in the Netherlands were extracted from the Netherlands Cancer Registry. The observed incidence after the suspension (March 2020-December 2020) was compared to the expected incidence in the same period. In the period April to June 2020, we observed the largest decrease in the total incidence of CRC. We found that 48% of the decrease was due to stage I, 23% due to stage II, 23% due to stage III and 5% due to stage IV. After gradually resuming screening mid May 2020, we observed an increase in CRC diagnoses from July 2020 onwards. As of October 2020, the observed number of diagnoses was higher than the expected number. As the decrease was mainly limited to stage I CRCs, it seems that the temporary suspension of the CRC screening programme due to the COVID-19 pandemic will have a minimal long-term impact on stage distribution and CRC mortality.

Use of antibiotics and colorectal cancer risk: a primary care nested case-control study in Belgium

OBJECTIVES

To examine the association between the use of oral antibiotics and subsequent colorectal cancer risk.

DESIGN

Matched case-control study.

SETTING

General practice centres participating in the Integrated Computerised Network database in Flanders, Belgium.

PARTICIPANTS

In total, 1705 cases of colorectal cancer diagnosed between 01 January 2010 and 31 December 2015 were matched to 6749 controls by age, sex, comorbidity and general practice centre.

PRIMARY OUTCOME MEASURE

The association between the number of prescriptions for oral antibiotics and the incidence of colorectal cancer over a period of 1-10 years, estimated by a conditional logistic regression model.

RESULTS

A significantly increased risk of colorectal cancer (OR 1.25, 95% CI 1.10 to 1.44) was found in subjects with one or more prescriptions compared with those with none after correction for diabetes mellitus. No dose-response relationship was found.

CONCLUSIONS

This study resulted in a modestly higher risk of having colorectal cancer diagnosed after antibiotic exposure. The main limitation was missing data on known risk factors, in particular smoking behaviour. This study did not allow us to examine the causality of the relationship, indicating the need of further investigation.

Incidence, mortality, survival, risk factor and screening of colorectal cancer: A comparison among China, Europe, and northern America

Colorectal cancer (CRC) is one of the most common malignancies worldwide. China, Europe and northern America account for more than half of the new CRC cases and associated deaths globally. This review summarizes the current status and temporal trends of CRC in China, Europe, and northern America. The potential primary preventive strategies and latest advances in CRC screening techniques and programs are discussed. Recently, the incidence and mortality of CRC in some European and northern American countries have decreased; conversely, CRC incidence and mortality continue to increase in China. The overall 5-year relative survival rate for CRC is similar between these regions, but there is considerable heterogeneity among European countries. Implementing population-based CRC screening programs can effectively address the growing disease burden. The effectiveness of nationwide CRC screening programs in these regions has been limited by relatively low coverage and participation rate. The deployment of state-of-the-art techniques and precise risk-adapted screening strategies incorporating effective risk prediction models and screening techniques may boost screening effectiveness. Our review provides novel foundations for the development and optimization of CRC preventive strategies.

Changes in rectal cancer treatment after the introduction of a national screening program; Increasing use of less invasive strategies within a national cohort

AIM

Organ preserving treatment strategies and the introduction of a colorectal cancer-screening program have likely influenced the resection rates of rectal cancer. The aim of this study is to assess the influence of these developments on rectal cancer treatment and resection rates in the Netherlands.

METHODS

Patients diagnosed with non-metastatic rectal cancer between 2013 and 2018, were selected from the Netherlands Cancer Registry. The distribution of surgical and neo-adjuvant treatment and resection rates were analyzed and compared over time.

RESULTS

Between 2013 and 2018 22640 patients were diagnosed with non-metastatic rectal cancer. The incidence of early stage (cT1) disease increased from 141 (4%) in 2013 to 448 (12%) in 2018. The use of neoadjuvant radiotherapy and chemo-radiotherapy dropped from 39% to 21% and 34%-25%, respectively. A decrease in surgical resection rates (including TEM) was observed from 85% to 73%. The proportion of patients who underwent endoscopic resections increased from 3% to 10%. The decrease in surgical resection rates was larger in patients treated with neo-adjuvant chemo-radiotherapy.

CONCLUSION

An increase in stage I disease is noted after the introduction of the screening program. Surgical resection rates for rectal cancer have fallen over time. Endoscopic resections due to more early-stage disease probably accounts for a large part of this decline. Furthermore, a watch and wait approach after neo-adjuvant chemo-radiotherapy may play an important role as well.

Colorectal cancer incidence, mortality, tumour characteristics, and treatment before and after introduction of the faecal immunochemical testing-based screening programme in the Netherlands: a population-based study

BACKGROUND

In 2014, a population-based colorectal cancer (CRC) screening programme was stepwise implemented in the Netherlands comprising faecal immunochemical testing once every 2 years, with a cutoff value for positivity of 47 μg haemoglobin per g faeces. We aimed to assess CRC incidence, mortality, tumour characteristics, and treatment before and after introduction of this screening programme.

METHODS

We did a retrospective, observational, population-based study in the Netherlands and gathered CRC incidence data from the Netherlands Cancer Registry from Jan 1, 2010, to Dec 31, 2019, in people aged 55 years or older. Patients with a CRC diagnosis between Jan 1, 2014, and Dec 31, 2018, in the Netherlands Cancer Registry were linked with the nationwide registry of histopathology and cytopathology (PALGA) to identify mode of detection (ie, screening-detected vs clinically detected). We calculated age-standardised CRC incidence rates and used data from Statistics Netherlands to calculate CRC-related mortality in 2010-19. We compared localisation, stage distribution, and treatment of screening-detected CRCs with clinically detected CRCs diagnosed in 2014-18 in patients aged 55-75 years.

FINDINGS

Between Jan 1, 2010, and Dec 31, 2019, 125 215 CRCs were diagnosed in individuals aged 55 years or older and were included in the analyses for CRC incidence. Before the introduction of the screening programme, the age-standardised CRC incidence rate was 214·3 per 100 000 population in 2013 in people aged 55 years or older. After the introduction of the screening programme, this rate initially increased to 259·2 per 100 000 population in 2015, and subsequently decreased to 181·5 per 100 000 population in 2019. Age-standardised incidence rates for advanced CRCs (stage III and IV) were 117·0 per 100 000 population in 2013 and increased to 122·8 per 100 000 population in 2015; this rate then decreased to 94·7 per 100 000 population in 2018. Age-standardised CRC mortality decreased from 87·5 deaths per 100 000 population in 2010 to 64·8 per 100 000 population in 2019. Compared with clinically detected CRCs, screening-detected CRCs were more likely to be located in the left side of the colon (48·6% vs 35·2%) and to be detected at an early stage (I or II; 66·7% vs 46·2%). Screening-detected CRCs were more likely to be treated by local excision compared with clinically detected CRCs, and this finding persisted when stage I CRCs were analysed separately.

INTERPRETATION

After introduction of this national screening programme, a decrease in overall and advanced-stage CRC incidence was observed. In view of this observation, together with the observed shift to detection at earlier stages and more screening-detected CRCs being treated by local excision, we might cautiously conclude that, in the long-term, faecal immunochemical testing-based screening could ultimately lead to a decrease in CRC-related morbidity and mortality.

FUNDING

None.

Faecal haemoglobin concentrations in women and men diagnosed with colorectal cancer in a national screening programme

Objective

There is evidence that colorectal cancer screening using faecal haemoglobin is less effective in women than men. The faecal haemoglobin concentrations were therefore examined in women and men with screen-detected colorectal cancer.

Setting

Scottish Bowel Screening Programme, following the introduction of a faecal immunochemical test from November 2017, to March 2020.

Methods

Data were collated on faecal haemoglobin concentrations, pathological stage and anatomical site of the main lesion in participants who had colorectal cancer detected. The data in women and men were compared.

Results

For the faecal haemoglobin concentrations studied (>80 µg Hb/g faeces), the distributions indicated lower concentrations in women. Marked differences were found between women and men diagnosed with colorectal cancer. The median faecal haemoglobin concentration for women (n = 720) was 408 µg Hb/g faeces compared to 473 µg Hb/g faeces for men (n = 959) (p = 0.004) and 50.6% of the results were >400 µg Hb/g faeces in women; in men, this was 57.8%. The difference in faecal haemoglobin concentrations in women and men became less statistically significant as stage advanced from stages I–IV. For right-sided, left-sided and rectal colorectal cancer, a similar gender difference persisted in all sites. Differences in faecal haemoglobin between the genders were significant for left-sided cancers and stage I and approached significance for rectal cancers and stage II, but all sites and stages showed lower median faecal haemoglobin concentrations for women.

Conclusions

To minimise gender inequalities, faecal immunochemical test-based colorectal cancer screening programmes should evaluate a strategy of using different faecal haemoglobin concentration thresholds in women and men.

Treatment of clinical T1 rectal cancer in the Netherlands; a population-based overview of clinical practice

INTRODUCTION

Local excision is increasingly used as an alternative treatment for radical surgery in patients with early stage clinical T1 (cT1) rectal cancer. This study provides an overview of incidence, staging accuracy and treatment strategies in patients with cT1 rectal cancer in the Netherlands.

MATERIALS AND METHODS

Patients with cT1 rectal cancer diagnosed between 2005 and 2018 were included from the Netherlands Cancer Registry. An overview per time period (2005-2009, 2010-2014 and 2015-2018) of the incidence and various treatment strategies used, e.g. local excision (LE) or major resection, with/without neoadjuvant treatment (NAT), were given and trends over time were analysed using the Chi Square for Trend test. In addition, accuracy of tumour staging was described, compared and analysed over time.

RESULTS

In total, 3033 patients with cT1 rectal cancer were diagnosed. The incidence of cT1 increased from 540 patients in 2005-2009 to 1643 patients in 2015-2018. There was a significant increased use of LE. In cT1N0/X patients, 9.2% received NAT, 25.5% were treated by total mesorectal excision (TME) and 11.4% received a completion TME (cTME) following prior LE. Overall accuracy in tumour staging (cT1 = pT1) was 77.3%, yet significantly worse in cN1/2 patients, as compared to cN0 patients (44.8% vs 77.9%, respectively, p < 0.001).

CONCLUSION

Over time, there was an increase in the incidence of cT1 tumours. Both the use of neoadjuvant therapy and TME surgery in clinically node negative patients decreased significantly. Clinical accuracy in T1 tumour staging improved over time, but remained significantly worse in clinical node positive patients.

Development and validation of a novel classification scheme for combining pathological T stage and log odds of positive lymph nodes for colon cancer

AIM

Log Odds of Positive Lymph Nodes (LODDS) have a better predictive ability than N stage for colon cancer. However, the prognostic value of developing a novel prognostic classification by combining T stage and LODDS (TLODDS) for colon cancer remains unknown. Therefore, in the present study, we aimed to develop a TLODDS classification for colon cancer, and assess whether or not the novel TLODDS classification could improve survival stratification by comparing its discrimination, model-fitting, and net benefits, with the American Joint Committee on Cancer (AJCC) Tumor/Node/Metastasis (TNM) classification.

METHODS

45,558 Western colon cancers were identified in the Surveillance, Epidemiology, and End Results database as a training set. A novel LODDS stage was established and patients with similar survival rates were grouped by combining T and LODDS stages to develop a novel TLODDS classification. The TLODDS classification was further assessed in a Chinese validation set of 3,515 colon cancers and an application set of 3,053 rectal cancers.

RESULTS

We developed a novel TLODDS classification that incorporated 7 stages: stage I (T1LODDS1), IIA (T2LODDS1, T1LODDS2, T1LODDS3), IIB (T2LODDS2-3, T3LODDS1, T1LODDS4), IIC (T3LODDS2, T2LODDS4, T4aLODDS1), IIIA (T3LODDS3, T1-2LODDS5, T4bLODDS1, T4aLODDS2), IIIB (T3LODDS4-5, T4aLODDS3-4, T4bLODDS2) and IIIC (T4bLODDS3-5, T4aLODDS5). In the training set, it showed significantly better discrimination (area under the receiver operating characteristic (ROC) curve, 0.691 vs. 0.664, P < 0.001), better model-fitting (Akaike information criteria, 265,644 vs. 267,410), and superior net benefits, than the latest AJCC TNM classification. The predictive performance of the TLODDS classification was further validated in colon cancers and was successfully applied in rectal cancers with regards to both overall and disease-free survival.

CONCLUSIONS

The TLODDS classification has better discriminatory ability, model-fitting, and net benefits than the existing TNM classification, and represents an alternative to the current TNM classifications for colon and rectal cancers.

MicroRNA-301b-3p facilitates cell proliferation and migration in colorectal cancer by targeting HOXB1

Previous studies revealed that miR-301b-3p was essential to the onset and development of several cancers, but the implied functions of miR-301b-3p in colorectal cancer (CRC) remained largely unclear. The current study is aimed to exploring the potential roles and possible mechanism of miR-301b-3p in CRC. The abundance of miR-301b-3p and HOXB1 in CRC clinical specimens and cell lines was verified using RT-qPCR. The CCK-8, colony formation, wound healing and transwell assays were adopted to evaluate cell proliferation and migration. The interactivity of miR-301b-3p and homeobox B1 (HOXB1) was identified using bioinformatics analysis and dual-luciferase reporter. The results of RT-qPCR indicated that miR-301b-3p was significantly upregulated in CRC clinical specimens and cell lines. Furthermore, overexpression of miR-301b-3p speeds up CRC cell proliferation and migration. Bioinformatics analysis and dual-luciferase reporter verified that HOXB1 acted as the downstream targeted mRNA. Furthermore, silencing of HOXB1 also obviously accelerated the proliferation and migration ability of CRC cells. miR-301b-3p facilitated cell proliferation and migration in CRC, which was partly reversed by overexpressing HOXB1. In conclusion, our findings demonstrated that miR-301b-3p facilitated CRC cell growth and migration via targeting HOXB1. Our results identified that miR-301b-3p served as a significant oncogene in CRC, which may provide a novel biomarker for diagnosis and therapeutic objective for CRC.

Features of colorectal cancer in China stratified by anatomic sites: A hospital-based study conducted in university-affiliated hospitals from 2014 to 2018

OBJECTIVE

The clinical and biological characteristics of colorectal cancer have been found to differ depending on the anatomic site of the cancer. However, for Chinese patients, there is limited information on the proportion of cases at each site and the related features. In this study, we explored the location, distribution and other features of colorectal cancers at each anatomic site in Chinese patients.

METHODS

We conducted a hospital-based study using hospitalization summary reports from 10 Peking University-affiliated hospitals from 2014 to 2018; the reports covered a total of 2,097,347 hospitalizations. Incident cases were chosen as the study population, and their epidemiological features were further analyzed.

RESULTS

A total of 20,739 colorectal cancer patients were identified. Rectum was the most common location (48.3%) of the cancer, whereas the proportions of patients with distal and proximal colon cancer were 24.5% and 18.6%, respectively. Patients with rectal cancer were predominantly male and were the youngest for all anatomical sites (each P<0.001). The highest proportion of emergency admissions, the longest hospital stays and the highest hospitalization costs were found in patients with proximal colon cancer (each P<0.001). The proximal colon cancer subgroup included the highest proportions of patients with medical histories of cholecystectomy, cholecystolithiasis and/or gallbladder polyps and appendectomy (P=0.009, P<0.001 and P<0.001, respectively). The distal colon cancer subgroup included the highest proportions of patients with medical histories of diabetes and hypertension (P<0.001, respectively).

CONCLUSIONS

The patterns of colorectal cancer observed in this study differ from those reported for Western patients and show a significantly higher proportion of patients with rectal cancer. Different epidemiological features were also found based on anatomic sites. Further studies based on tumor location should be conducted to facilitate more accurate screening and treatment.