Familial colorectal cancer: A review

Optimizing genetic testing strategy for suspected attenuated adenomatous polyposis: effective solutions in public health systems

BACKGROUND

APC and MUTYH genes are key in hereditary attenuated adenomatous polyposis syndromes. Guidelines recommend genetic testing based on polyp count, often overlooking age despite its impact on polyp prevalence.

AIM

To enhance genetic testing strategies for suspected attenuated adenomatous polyposis by combining polyp count and age in a probability calculator.

METHODS

Retrospective study of adult patients referred to NGS genetic testing for suspected attenuated adenomatous polyposis (accumulated history of < 100 adenomas) (discovery cohort, N = 138). Data included age, adenoma count, and test results. A multivariable logistic regression model was developed to associate positive genetic test results with age and adenoma count. The model was externally validated with 259 patients from two tertiary hospitals in our region (validation cohort, N = 259).

RESULTS

In the discovery cohort, 13 (9.4%) patients had pathogenic mutations, being younger (OR:0.91, 95%CI 0.86-0.96) and having more adenomas (OR:1.08, 95%CI 1.04-1.13) compared to negative cases. The logistic regression model combining age and polyp count demonstrated an AUC of 0.92. Using a cutoff probability of 3.5%, the model achieved 100% sensitivity and 58% specificity in identifying positive cases. In the external validation, the model accurately predicted 14 out of 16 positive cases (88%). The remaining two positive cases were a patient with an AXIN2 mutation in heterozygosis, and a patient with a NTHL1 mutation in homozygosis. Performance evaluation of both hospitals yielded AUC values of 0.77 and 0.90.

CONCLUSIONS

Older individuals with fewer polyps are less likely have hereditary syndromes. Including age in genetic testing criteria can enhance patient selection and cost-effectiveness.

Colorectal Cancer: Risk Factors, Novel Approaches in Molecular Screening and Treatment

By 2040 the burden of colorectal cancer will increase to 3.2 million new cases per year and 1.6 million deaths per year. This highlights the importance of improving preventive measures and treatment strategies. This piece concisely overviews the latest therapeutic and diagnostic approaches for colorectal cancer. In 2019, factors such as low milk intake, smoking, insufficient calcium consumption, and alcohol use had a significant impact on colorectal cancer DALYs worldwide. A comprehensive search was conducted in December 2023 using keywords related to drugs, therapeutic agents, colorectal cancer, diagnostic methods, epidemiology, and novel therapeutic approaches in the PubMed and Scopus databases. Initially, 325 articles were identified based on titles, abstracts, and publication dates. After removing duplicates, 170 unique articles were included. Medications like Nimotuzumab, Cetuximab, and Panitumumab target the Epidermal Growth Factor Receptor (EGFR), which EGF activates. HER2, activated by ligands, is the focus of drugs like Trastuzumab and Pertuzumab. The PD-1/PD-L1 and CTLA-4 pathways, as the immune checkpoints, which involve T cells, are targeted by medications like Ipilimumab. Adoptive cell therapy, including CAR-T cell therapy, TCR modification, and enhancing T cell activity through tumor-infiltrating lymphocytes, is used to combat cancer cell growth. In medical advancements, adoptive cell transfer therapy (ACT) and exosomes in the tumor immune microenvironment (TME) are notable treatment methods that boost the immune system. HIF1A-AS1, CRNDE-h, NEAT1, ZFAS1, and GAS5, along with IGFBP-2, have demonstrated significant CRC diagnostic capacity. Compared to CRC patients with low HIF1A-AS1 expression, individuals with high expression levels were linked to a worse 5-year survival rate.

Whole Exome-Wide Association Identifies Rare Variants in APC Associated with High-Risk Colorectal Cancer in the Middle East

Background: Colorectal cancer (CRC) displays a complex pattern of inheritance. It is postulated that much of the missing heritability of CRC is enriched in high-impact rare alleles, which might play a crucial role in the etiology and susceptibility of CRC. Methods: In this study, an exome-wide association analysis was performed in 146 patients with high-risk CRC in the Middle East and 1395 healthy controls. The aim was to identify rare germline variants in coding regions and their splicing sites associated with high-risk CRC in the Middle Eastern population. Results: Rare inactivating variants (RIVs) in APC had the strongest association with high-risk CRC (6/146 in cases vs. 1/1395 in controls, OR = 59.7, p = 5.13 × 10-12), whereas RIVs in RIMS1, an RAS superfamily member, were significantly associated with high-risk CRC (5/146 case vs. 2/1395 controls, OR = 24.7, p = 2.03 × 10-8). Rare damaging variants in 17 genes were associated with high-risk CRC at the exome-wide threshold (p < 2.5 × 10-6). Based on the sequence kernel association test, nonsynonymous variants in six genes (TNXB, TAP2, GPSM3, ADGRG4, TMEM229A, and ANKRD33B) had a significant association with high-risk CRC. RIVs in APC-the most common high-penetrance genetic factor-were associated with patients with high-risk CRC in the Middle East. Individuals who inherited APC RIVs had an approximate 60-fold increased risk of developing CRC and were likely to develop the disease earlier. Conclusions: We identified new potential CRC predisposition variants in other genes that could play a role in CRC inheritance. However, large collaborative studies are needed to confirm the association of these variants with high-risk CRC. These results provide information for counseling patients with high-risk CRC and their families in our population.

Association of healthy diet score and adiposity with risk of colorectal cancer: findings from the UK Biobank prospective cohort study

PURPOSE

To explore the joint association of dietary patterns and adiposity with colorectal cancer (CRC), and whether adiposity mediates the relationship between dietary patterns and CRC risk, which could provide deeper insights into the underlying pathogenesis of CRC.

METHODS

The data of 307,023 participants recruited between 2006 and 2010 were extracted from the UK Biobank study. Healthy diet scores were calculated based on self-reported dietary data at baseline, and participants were categorized into three groups, namely, low, intermediate, and high diet score groups. Cox regression models with hazard ratios (HRs) and 95% confidence intervals (CIs) were used to estimate the effects of the healthy diet score on CRC incidence, adjusting for various covariates. Furthermore, the mediation roles of obesity and central obesity between the healthy diet score and CRC risk were assessed using a counterfactual causal analysis based on Cox regression model. Additionally, joint association between dietary patterns and adiposity on CRC risks was assessed on the additive and multiplicative scales.

RESULTS

Over a median 6.2-year follow-up, 3,276 participants developed CRC. After adjusting for sociodemographic and lifestyle factors, a lower risk of CRC incidence was found for participants with intermediate (HR = 0.83, 95% CI: 0.72 to 0.95) and high diet scores (HR = 0.73, 95% CI: 0.62 to 0.87) compared to those with low diet scores. When compared with the low diet score group, obesity accounted for 4.13% and 7.93% of the total CRC effect in the intermediate and high diet score groups, respectively, while central obesity contributed to 3.68% and 10.02% of the total CRC risk in the intermediate and high diet score groups, respectively. The mediating effect of adiposity on CRC risk was significant in men but not in women. Concurrent unhealthy diet and adiposity multiplied CRC risk.

CONCLUSION

Adiposity-mediated effects were limited in the link between dietary patterns and CRC incidence, implying that solely addressing adiposity may not sufficiently reduce CRC risk. Interventions, such as improving dietary quality in people with adiposity or promoting weight control in those with unhealthy eating habits, may provide an effective strategy to reduce CRC risk.

Comparative Analysis of miRNA and EMT Markers in Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the fourth most commonly diagnosed malignant condition in the world. Micro RNAs (miRNAs) as well as epithelial to mesenchymal transition (EMT) play an important role in the pathogenesis of CRC. We performed a comparative analysis of the expression of selected miRNA genes and EMT markers in bioptic samples from patients (n = 45) with primary CRC or metastatic (m)CRC to the regional lymph node using reverse transcription-quantitative PCR and IHC staining. Results: Out of all miRNA analyzed, the miR-17 expression was most significantly different and associated with lower risk of CRC spread to the lymph node. In addition, significant relationships were found between the tumor side localization and several miRNAs expressions (miR-9, miR-29b, miR-19a, miR-19b, miR-21, miR-106a, miR-20a and miR-17). In addition, of the examined EMT markers, only VEGFA expression correlated with tumor progression (tumor grade G2). In the examined set of patient samples and their matched healthy tissue, several specific molecular markers (miRNAs associated with EMT and tumor progression) were identified with a promising prognostic potential. Their further examination in larger patient cohorts is planned to validate the present data.

Family history of cancer as a potential risk factor for colorectal cancer in EMRO countries: a systematic review and meta-analysis

The current meta-analysis aims to investigate the existing articles that evaluated the implications of a positive family history of cancer on the risk of colorectal cancer (CRC) within the EMRO countries. We employed PubMed, Scopus, and Web of Science as search databases for this study. To assess the quality of the selected articles, we utilized the Newcastle-Ottawa (NCO) checklist. In comparing the impact of a family history of cancer between the case and control groups, we computed the odds ratio (OR) along with its corresponding 95% confidence interval (CI). Finally, 27 articles were selected for meta-analysis. The result of the meta-analysis showed a significant association between the presence of a family history of CRC or any cancers and CRC (OR 2.21; 95% CI 1.54-3.17; P < 0.001, OR 1.76; 95% CI 1.27-2.42; P = 0.001, respectively). Our findings underscore the critical importance of timely screening and early identification for individuals with a family history of cancer. By fostering close coordination among healthcare facilities and actively promoting the adoption of screening methods for early detection, we have the potential to significantly reduce both mortality rates and financial burdens of CRC on the general public, ultimately leading to enhanced patient outcomes.

Molecular pathology of colorectal cancer: The Saudi situation in perspective

Colorectal cancer (CRC) is one of the most common cancers worldwide, and one of the most common causes of cancer deaths. In recent times, significant advancements have been made in elucidating the molecular alterations of the disease, and the results have been an improved understanding of CRC biology, as well as the discovery of biomarkers of diagnostic, prognostic, and therapeutic significance. In this review, an evaluation is carried out of the molecular pathology research of CRC emanating from Saudi Arabia. The verdict is that the data on the molecular alterations in CRC from Saudi patients is at best modest. This dearth of molecular pathology data is aptly reflected in the paucity of molecular markers recommended for testing by the Saudi National Cancer Centre guidelines for CRC management. Large scale multi-institutional and multiregional translational studies are required to generate molecular data that would inform diagnostic, prognostic, and risk-stratification guidelines for Saudi CRC patients.

Surveillance Outcomes in Patients With a Family History of Colorectal Cancer in Both Parents

Background and Aims

A family history of colorectal cancer (CRC) in a first-degree relative is a well-established risk factor for CRC. When individuals have 2 parents with CRC, the impact on risk is uncertain, and there are no established guidelines for surveillance. We sought to define the surveillance practices and outcomes in individuals with a family history of CRC in both parents.

Methods

We identified probands with a family history of CRC in both parents from our Hereditary Gastrointestinal Cancer Database. Charts were retrospectively reviewed for colonoscopy surveillance patterns and incidence of adenomas and CRC.

Results

Sixty-six patients met the inclusion criteria. Forty-two patients (64%) had genetic testing, and no pathogenic germline mutations were identified. During a mean surveillance period of 144 ± 82.2 months and a mean surveillance interval of 33.4 ± 16.6 months, a total of 3.2 ± 8.9 adenomas were found per patient. These were small (median 6.5 mm), and 96% exhibited only low-grade dysplasia. Six patients (9%) were diagnosed with CRC at a mean age of 61.5 ± 11.3 years, corresponding to an incidence rate of 14 cases/10,000 person-years. Patients with CRC were older at first colonoscopy than those without cancer (59 vs 46 years, P = .03), and half of these cases were diagnosed at this first colonoscopy.

Conclusion

Among patients with a family history of CRC in both parents, cases of CRC were seen primarily in those who significantly delayed their first colonoscopy. Initiation of colonoscopy at age 40 should be recommended to individuals with CRC in both parents, consistent with recommendations for those with 1 first-degree relative with CRC.

Overview of microRNAs as liquid biopsy biomarkers for colorectal cancer sub-type profiling and chemoresistance

Colorectal cancer (CRC) is the third most common cancer worldwide. It has also been demonstrated that over the last ten years the incidence of CRC among younger people below the age of 50 is also increasing. Screening for colorectal cancer is of utmost importance; the rationale behind screening is to target the malignancy and reduce the incidence and mortality of the disease. Diagnostic methods to screen for incidence or relapse are therefore a requisite to detect cancer as early as possible. Scientific findings demonstrate that many deaths are due to lack of screening and therefore early identification will lead to greater survivability. In colorectal cancer, diagnostic tests include liquid biopsy biomarkers. Since the discovery of microRNAs (miRNAs), many studies have demonstrated the relationship between miRNAs and the various sub-types of CRC. Several miRNAs have been identified after analysing serum or plasma samples in patients, and such miRNAs were found to be significantly dysregulated. Such findings place the possibility of miRNAs to be at the epicentre of novel diagnostic techniques for CRC identification and sub-type stratification, including other characteristics associated with CRC development such as patient prognosis. The following review serves to underline the latest findings for miRNAs with such potential for routine diagnostic employment in CRC diagnostics and treatments.

Cannabinoids, Medical Cannabis, and Colorectal Cancer Immunotherapy

Colorectal cancer is a major public health problem. Unfortunately, currently, no effective curative option exists for this type of malignancy. The most promising cancer treatment nowadays is immunotherapy which is also called biological or targeted therapy. This type of therapy boosts the patient's immune system ability to fight the malignant tumor. However, cancer cells may become resistant to immunotherapy and escape immune surveillance by obtaining genetic alterations. Therefore, new treatment strategies are required. In the recent decade, several reports suggest the effectiveness of cannabinoids and Cannabis sativa extracts for inhibiting cancer proliferation in vitro and in vivo, including intestinal malignancies. Cannabinoids were shown to modulate the pathways involved in cell proliferation, angiogenesis, programmed cell death and metastasis. Because of that, they are proposed as adjunct therapy for many malignancies. By far less information exists on the potential of the use of cannabis in combination with immunotherapy. Here, we explore the possibility of the use of cannabinoids for modulation of immunotherapy of colon cancer and discuss possible advantages and limitations.

WRN Germline Mutation Is the Likely Inherited Etiology of Various Cancer Types in One Iranian Family

Background

Familial cancers comprise a considerable distribution of colorectal cancers (CRCs), of which only about 5% occurs through well-established hereditary syndromes. It has been demonstrated that deleterious variants at the newly identified cancer-predisposing genes could describe the etiology of undefined familial cancers.

Methods

The present study aimed to identify the genetic etiology in a 32-year-old man with early onset familial CRC employing several molecular diagnostic techniques. DNA was extracted from tumoral and normal formalin-fixed-paraffin-embedded (FFPE) blocks, and microsatellite instability (MSI) was evaluated. Immunohistochemistry staining of MMR proteins was performed on tumoral FFPE blocks. Next-generation sequencing (NGS), multiplex ligation-dependent amplification (MLPA) assay, and Sanger sequencing were applied on the genomic DNA extracted from peripheral blood. Data analysis was performed using bioinformatics tools. Genetic variants interpretation was based on ACMG.

Results

MSI analysis indicated MSI-H phenotype, and IHC staining proved no expressions of MSH2 and MSH6 proteins. MLPA and NGS data showed no pathogenic variants in MMR genes. Further analysis of NGS data revealed a candidate WRN frameshift variant (p.R389Efs*3), which was validated with Sanger sequencing. The variant was interpreted as pathogenic since it met the criteria based on the ACMG guideline including very strong (PVS1), strong (PS3), and moderate (PM2).

Conclusion

WRN is a DNA helicase participating in DNA repair pathways to sustain genomic stability. WRN deficient function may contribute to CRC development that is valuable for further investigation as a candidate gene in hereditary cancer syndrome diagnosis.

Family history of colorectal cancer and survival: a Swedish population-based study

OBJECTIVES

A family history of colorectal cancer (CRC) is an established risk factor for developing CRC, whilst the impact of family history on prognosis is unclear. The present study assessed the association between family history and prognosis and, based on current evidence, explored whether this association was modified by age at diagnosis.

METHODS

Using data from the Swedish Colorectal Cancer Registry (SCRCR) linked with the Multigeneration Register and the National Cancer Register, we identified 31 801 patients with a CRC diagnosed between 2007 and 2016. The SCRCR is a clinically rich database which includes information on the cancer stage, grade, location, treatment, complications and postoperative follow-up.

RESULTS

We estimated excess mortality rate ratios (EMRR) for relative survival and hazard ratios (HR) for disease-free survival with 95% confidence intervals (CIs) using flexible parametric models. We found no association between family history and relative survival (EMRR = 0.96, 95% CIs: 0.89-1.03, P = 0.21) or disease-free survival (HR = 0.98, 95% CIs: 0.91-1.06, P = 0.64). However, age was found to modify the impact of family history on prognosis. Young patients (<50 at diagnosis) with a positive family history had less advanced (i.e. stages I and II) cancers than those with no family history (OR = 0.71, 95% CI: 0.56-0.89, P = 0.004) and lower excess mortality even after adjusting for cancer stage (EMMR = 0.63, 95% CIs: 0.47-0.84, P = 0.002).

CONCLUSIONS

Our results suggest that young individuals with a family history of CRC may have greater health awareness, attend opportunistic screening and adopt lifestyle changes, leading to earlier diagnosis and better prognosis.

Evaluating the effects of a risk-adapted screening program for familial colorectal cancer in individuals between 25 and 50 years of age: study protocol for the prospective population-based intervention study FARKOR

BACKGROUND

Colorectal cancer (CRC) is the second most common malignant disease and the second most common cause of cancer death in Germany. Official CRC screening starts at age 50. As there is evidence that individuals with a family history of CRC have an increased risk of developing CRC before age 50, there are recommendations to start screening for this group earlier. This study aims to evaluate the clinical and economic effects of a risk-adapted screening program for CRC in individuals between 25 and 50 years of age with potentially increased familial CRC risk.

METHODS

FARKOR (Familiäres Risiko für das Kolorektale Karzinom) is a population-based prospective intervention study. All members of cooperating statutory health insurance companies between 25 and 50 years of age living in a model region in Germany (federal state of Bavaria, 3.5 million inhabitants in this age group) can participate in the program between October 2018 and March 2020. Recruitment takes place through physicians and through a public campaign. Additionally, insurances contact recently diagnosed CRC patients in order to encourage their relatives to participate in the program. Physicians assess a participant's familial history of CRC using a short questionnaire. All participants with a family history of CRC are invited to a shared decision making process to decide on further screening options consisting of either undergoing an immunological test for fecal occult blood or colonoscopy. Comprehensive data collection based on self-reported lifestyle information, medical documentation and health administrative databases accompanies the screening program. Longterm benefits, harms and the cost-effectiveness of the risk-adapted CRC screening program will be assessed by decision analytic modeling.

DISCUSSION

The data collected in this study will add important pieces of information that are still missing in the evaluation of the effects and the cost-effectiveness of a risk-adapted CRC screening strategy for individuals under 50 years of age.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS-IDDRKS00015097.

Promising Colorectal Cancer Biomarkers for Precision Prevention and Therapy

Colorectal cancer (CRC) has been ranked as the third most prevalent cancer worldwide. Indeed, it represents 10.2% of all cancer cases. It is also the second most common cause of cancer mortality, and accounted for about 9.2% of all cancer deaths in 2018. Early detection together with a correct diagnosis and staging remains the most effective clinical strategy in terms of disease recovery. Thanks to advances in diagnostic techniques, and improvements of surgical adjuvant and palliative therapies, the mortality rate of CRC has decreased by more than 20% in the last decade. Cancer biomarkers for the early detection of CRC, its management, treatment and follow-up have contributed to the decrease in CRC mortality. Herein, we provide an overview of molecular biomarkers from tumor tissues and liquid biopsies that are approved for use in the CRC clinical setting for early detection, follow-up, and precision therapy, and of biomarkers that have not yet been officially validated and are, nowadays, under investigation.

Update on Sporadic Colorectal Cancer Genetics

Our understanding of the genetics of colorectal cancer has changed dramatically over recent years. Colorectal cancer can be classified in multiple different ways. Along with the advent of whole-exome sequencing, we have gained an understanding of the scale of the genetic changes found in sporadic colorectal cancer. We now know that there are multiple pathways that are commonly involved in the evolution of colorectal cancer including Wnt/β-catenin, RAS, EGFR, and PIK3 kinase. Another recent leap in our understanding of colorectal cancer genetics is the recognition that many, if not all tumors, are actually genetically heterogeneous within individual tumors and also between tumors. Recent research has revealed the prognostic and possibly therapeutic implications of various specific mutations, including specific mutations in BRAF and KRAS . There is increasing interest in the use of mutation testing for screening and surveillance through stool and circulating DNA testing. Recent advances in translational research in colorectal cancer genetics are dramatically changing our understanding of colorectal cancer and will likely change therapy and surveillance in the near future.

Efficacy of a Telehealth Intervention on Colonoscopy Uptake When Cost Is a Barrier: The Family CARE Cluster Randomized Controlled Trial

BACKGROUND

We tested the efficacy of a remote tailored intervention Tele-Cancer Risk Assessment and Evaluation (TeleCARE) compared with a mailed educational brochure for improving colonoscopy uptake among at-risk relatives of colorectal cancer patients and examined subgroup differences based on participant reported cost barriers.

METHODS

Family members of colorectal cancer patients who were not up-to-date with colonoscopy were randomly assigned as family units to TeleCARE (N = 232) or an educational brochure (N = 249). At the 9-month follow-up, a cost resource letter listing resources for free or reduced-cost colonoscopy was mailed to participants who had reported cost barriers and remained nonadherent. Rates of medically verified colonoscopy at the 15-month follow-up were compared on the basis of group assignment and within group stratification by cost barriers.

RESULTS

In intent-to-treat analysis, 42.7% of participants in TeleCARE and 24.1% of participants in the educational brochure group had a medically verified colonoscopy [OR, 2.37; 95% confidence interval (CI) 1.59-3.52]. Cost was identified as a barrier in both groups (TeleCARE = 62.5%; educational brochure = 57.0%). When cost was not a barrier, the TeleCARE group was almost four times as likely as the comparison to have a colonoscopy (OR, 3.66; 95% CI, 1.85-7.24). The intervention was efficacious among those who reported cost barriers; the TeleCARE group was nearly twice as likely to have a colonoscopy (OR, 1.99; 95% CI, 1.12-3.52).

CONCLUSIONS

TeleCARE increased colonoscopy regardless of cost barriers.

IMPACT

Remote interventions may bolster screening colonoscopy regardless of cost barriers and be more efficacious when cost barriers are absent.