A new hereditary colorectal cancer network in the Middle East and eastern mediterranean countries to improve care for high-risk families

Cancer Genetics in the Arab World

Cancer remains a major global health burden, with incidence rates rising globally. The Arab world, which is often regarded as an underrepresented population in literature, shows distinct patterns in cancer incidences, genetics, and outcomes in comparison with Western populations. This review aims to highlight key genomic studies conducted in the Arab world. We describe the epidemiological and genetic landscape of cancer in the Arab populations, focusing on lung, breast, and colorectal cancers, given their prominence and distinctive patterns in the region. We utilised data from GLOBOCAN 2022 and published genomic studies to assess subregional incidence trends, identify significant mutations, and explore hereditary and early-onset cancers profiles. Breast, lung, and colorectal cancers dominate the cancer profile in the region, with disparities in genetic alterations when compared to global trends. Variation in EGFR mutation frequencies in lung cancer across diverse ethnicities in the MENA region is representative of the extreme heterogeneity in the Arab region. Variations in BRCA1/2 mutation frequency, and unique founder mutations highlight breast cancer's particular regional genetic traits. Similarly, colorectal cancer studies show variations in mutational profiles, such as a low incidence of BRAF mutations and distinct epigenetic characteristics that represent region-specific disease pathways. Early-onset cancers, particularly breast and colorectal cancers, occur at higher rates than in Western populations and often diverge from the typical germline mutation patterns reported globally. The review emphasises the importance of conducting localised genetic studies in improving personalised medicine and public health strategies. Despite these efforts, significant gaps remain, particularly in understanding early-onset cancers and hereditary cancer genetic disorders, which are overrepresented in the region. Further research on the genetic basis of cancer in Arab populations is essential for advancing personalised treatment and improving cancer outcomes in these under-researched groups.

"There should be one spot that you can go:" BRCA mutation carriers' perspectives on cancer risk management and a hereditary cancer registry

Individuals who carry BRCA1 or BRCA2 pathogenic variants are recommended to have extensive cancer prevention screening and risk-reducing surgeries. Uptake of these recommendations is variable, and there remains room for improvement in the risk management of BRCA carriers. This paper explores female BRCA carriers' experiences with the current model of care and their perspectives on (and interest in) an inherited cancer registry. Findings can inform the development of a dedicated high-risk screening and management program for these patients. Quantitative and qualitative data were gathered through a provincial descriptive survey and semi-structured qualitative interviews to assess BRCA carriers' opinions toward risk management services in the province of Newfoundland and Labrador (NL), Canada. Survey (n = 69) and interview data (n = 15) revealed continuity and coordination challenges with the current system of care of high-risk individuals. Respondents suggested an inherited cancer registry would help identify high-risk individuals and provide a centralized system of risk management for identified carriers. Respondents identified concerns about the privacy of their registry data, including who could access it. Findings suggest BRCA carriers see great value in an inherited cancer registry. Specifically, participants noted it could provide a centralized system to help improve the coordination of burdensome, life-long risk management. Important patient concerns about protecting their privacy and their health data confidentiality must be addressed in patient and public information and informed consent documents about a registry.

Colorectal Cancer Screening in the Middle East: What, Why, Who, When, and How?

The incidence of colorectal cancer (CRC) in the Middle East is increasing, especially among those younger than 50 years. Risk factors including obesity, sedentary lifestyle, and dietary changes are associated with the epidemiologic shift and are a result of socioeconomic changes happening in the region. Worldwide, CRC screening is associated with decreased incidence and mortality of CRC, but screening uptake is still low in the Middle East because of cultural barriers and lack of awareness; in addition, most countries do not have national screening programs. Knowledge of CRC screening and participation rates vary among different countries, but overall they are low. Both primary and secondary prevention approaches are needed in the Middle East, and cost-effectiveness is important in choosing screening modalities. Although colonoscopy is considered the most robust screening method, stool-based testing may be an acceptable screening strategy in resource-limited settings, and focusing on high-risk individuals such as those with hereditary CRC might be the most cost-effective strategy. In addition to financial limitations in many countries in the Middle East, human displacement places an extra toll on cancer control strategies in the region.

High prevalence of MUTYH associated polyposis among minority populations in Israel, due to rare founder pathogenic variants

BACKGROUND

Autosomal recessive conditions are common in consanguineous populations. Since consanguinity is common in the Israeli Arab population, we evaluated the rate of MUTYH polyposis (MAP) among polyposis patients in this population and studied Pathogenic Variants (PVs) spectrum.

METHODS

We reviewed health records of all Arab and Druze polyposis patients referred for counseling during 2013-2020 who fulfilled the Israeli Genetic Society criteria for MUTYH/APC testing, in a tertiary center in Northern Israel and four additional gastro-genetic clinics in Israel.

RESULTS

The Northern cohort included 37 patients from 30 unrelated families; 8(26.6%) carried bi-allelic MUTYH PVs. The major variant p.Glu452del was detected in 6/8 Druze and Muslim families who shared the same haplotype. Other PVs detected in both cohorts included p.Tyr56Ter, p.His57Arg, c.849+3A>C, p.Ala357fs, and p.Tyr151Cys. Among bi-allelic carriers, 88% reported consanguinity, and 100% had positive family history for polyposis or colorectal cancer (CRC). Generally, the age of CRC was 10 years younger than reported in the general MAP population.

CONCLUSIONS

MAP accounted for 27% of polyposis cases in the Arab population of Northern Israel. PVs spectrum is unique, with high frequency of the founder variant p.Glu452del. Our results may inform the genetic testing strategy in the Israeli Arab population.

A Focused Clinical Review of Lynch Syndrome

Lynch syndrome (LS) is an autosomal dominant condition that increases an individual's risk of a constellation of cancers. LS is defined when an individual has inherited pathogenic variants in the mismatch repair genes. Currently, most people with LS are undiagnosed. Early detection of LS is vital as those with LS can be enrolled in cancer reduction strategies through chemoprophylaxis, risk reducing surgery and cancer surveillance. However, these interventions are often invasive and require refinement. Furthermore, not all LS associated cancers are currently amenable to surveillance. Historically only those with a strong family history suggestive of LS were offered testing; this has proved far too restrictive. New criteria for testing have recently been introduced including the universal screening for LS in associated cancers. This has increased the number of people being diagnosed with LS but has also brought about unique challenges such as when to consent for germline testing and questions over how and who should carry out the consent. The results of germline testing for LS can be complicated and the diagnostic pathway is not always clear. Furthermore, by testing only those with cancer for LS we fail to identify these individuals before they develop potentially fatal pathology. This review will outline these challenges and explore solutions. Furthermore, we consider the potential future of LS care and the related treatments and interventions which are the current focus of research.

The associations between interleukin-17 single-nucleotide polymorphism and colorectal cancer susceptibility: a systematic review and meta-analysis

Background

Numerous case-control studies have reported associations between interleukin-17 (IL-17) polymorphisms and colorectal cancer; however, the results were inconsistent. The aim of this meta-analysis was to further clarify the effects of IL-17 polymorphisms on colorectal cancer susceptibility.

Materials and method

Relevant studies were extracted from the electronic databases PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CMB) up to April 2021. The odds ratio and 95% confidence interval were used to estimate the strength of the associations.

Results

Ten articles including 2599 cases and 2845 controls were enrolled in our research after strict literature screening. Highly significant associations between the IL-17A rs2275913 polymorphism and increased colorectal cancer susceptibility were observed in all five gene models (allelic, dominant, recessive, homozygous, and heterozygous models), and subgroup analysis based on ethnicity revealed that these associations existed not only in the Asian population but also in the Caucasian population. However, the results showed no significantly elevated colorectal cancer risk correlated with the IL-17F rs763780 polymorphism, and a slightly lower colorectal cancer susceptibility for the Caucasian population was discovered in the recessive and homozygous models of this mutation.

Conclusion

The IL-17A rs2275913 polymorphism may be an independent risk factor contributing to colorectal cancer susceptibility, while the IL-17F rs763780 polymorphism may decrease susceptibility to colorectal cancer. Future studies with large-scale samples are warranted to identify these associations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02586-2.

Identification and management of Lynch syndrome in the Middle East and North African countries: outcome of a survey in 12 countries

BACKGROUND

Lynch syndrome (LS), the most common inherited form of colorectal cancer (CRC), is responsible for 3% of all cases of CRC. LS is caused by a mismatch repair gene defect and is characterized by a high risk for CRC, endometrial cancer and several other cancers. Identification of LS is of utmost importance because colonoscopic surveillance substantially improves a patient's prognosis. Recently, a network of physicians in Middle Eastern and North African (ME/NA) countries was established to improve the identification and management of LS families. The aim of the present survey was to evaluate current healthcare for families with LS in this region.

METHODS

A questionnaire was developed that addressed the following issues: availability of clinical management guidelines for LS; attention paid to family history of cancer; availability of genetic services for identification and diagnosis of LS; and assessment of knowledge of LS surveillance. Members of the network and authors of recent papers on LS from ME/NA and neighbouring countries were invited to participate in the survey and complete the online questionnaire.

RESULTS

A total of 55 individuals were invited and 19 respondents from twelve countries including Algeria, Azerbaijan, Cyprus, Egypt, Iran, Jordan, Kuwait, Lebanon, Morocco, Palestine, Tunisia, and Turkey completed the questionnaire. The results showed that family history of CRC is considered in less than half of the surveyed countries. Guidelines for the management of LS are available in three out of twelve countries. The identification and selection of families for genetic testing were based on clinical criteria (Amsterdam criteria II or Revised Bethesda criteria) in most countries, and only one country performed universal screening. In most of the surveyed countries genetic services were available in few hospitals or only in a research setting. However, surveillance of LS families was offered in the majority of countries and most frequently consisted of regular colonoscopy.

CONCLUSION

The identification and management of LS in ME/NA countries are suboptimal and as a result most LS families in the region remain undetected. Future efforts should focus on increasing awareness of LS amongst both the general population and doctors, and on the improvement of the infrastructure in these countries.