Hereditary cancer syndromes in Latino populations: genetic characterization and surveillance guidelines

A comprehensive characterization of the spectrum of MUTYH germline pathogenic variants in Latin America

MUTYH-Associated Polyposis (MAP) is caused by biallelic pathogenic germline variants in the MUTYH gene. However, individuals harboring monoallelic MUTYH pathogenic variants in the presence of a positive family history have been reported to have a twofold increased risk of colorectal cancer (CRC) and extra colonic cancers. Our aim was to characterize the spectrum of monoallelic and biallelic germline MUTYH pathogenic variants in Latin American patients and to describe their clinical and genetic characteristics. Patients were identified from eight high-risk genetic cancer centers of five Latin American countries. Statistical analysis was performed using the two-sided P test using the Vassarstats statistical tools. Statistical significance was set at a p value ≤ 0.05. Of the 105 unrelated patients with cancer or colorectal polyposis, 84.8% and 15.2% carried pathogenic monoallelic and biallelic MUTYH variants, respectively. The most common pathogenic variants were p.Gly396Asp and p.Tyr179Cys (55% and 23%, respectively). The mean age at first diagnosis was 48.29 years (range 31-71) and 49.90 years (range 27-87) in biallelic and monoallelic MUTYH patients, respectively. CRC was the only cancer diagnosed in patients with biallelic MUTYH pathogenic variants (75%), while breast cancer (46.1%) was more common than CRC (24.7%) in individuals with monoallelic MUTYH pathogenic variants. We reported a high frequency of European founder variants in our diverse population. Some phenotypic differences from current studies were identified, such as a higher breast cancer burden in monoallelic carriers and a complete absence of extra-colon tumors in biallelic patients.

Breast Cancer Risk Perceptions Among Underserved, Hispanic Women: Implications for Risk-Based Approaches to Screening

BACKGROUND

Understanding factors that shape breast cancer risk perceptions is essential for implementing risk-based approaches to breast cancer detection and prevention. This study aimed to assess multilevel factors, including prior screening behavior, shaping underserved, Hispanic women's perceived risk for breast cancer.

METHODS

Secondary analysis of survey data from Hispanic women (N = 1325, 92% Spanish speaking, 64% < 50) enrolled in a large randomized controlled trial. Analyses were performed in two cohorts to account for the role of age on screening guideline recommendations (< 50 and 50 +). For each cohort, we examined differences in three common measures of perceived risk of breast cancer (percent lifetime, ordinal lifetime, comparative) by participant factors with chi-square or Kruskal-Wallis tests, as appropriate. Multivariate analyses examined the association between mammography history with percent perceived lifetime risk (outcome > 10 vs ≤ 10%).

RESULTS

Overall, 75% reported a lifetime risk between 0 and 10%, 96% rated their ordinal risk as "not high," and 50% rated their comparative risk as "much lower." Women < 50 with a family history of breast cancer reported significantly higher levels of perceived risk across all three measures. Among women 50 + , those reporting lower levels of perceived risk were significantly more likely to be Spanish speaking. No significant association was observed between mammography history and percent lifetime risk of breast cancer.

CONCLUSION

Factors shaping breast cancer risk perceptions differ by age. Prior screening may play less of role in constructing risk perceptions. Research is needed to develop culturally and linguistically appropriate strategies to improve implementation of risk-based screening.

Role of microRNA in colorectal carcinoma (CRC): a narrative review

MicroRNAs (miRNAs) are short non-coding RNAs that play a critical role in regulating gene expression by binding to target messenger RNAs (mRNAs). They were first discovered around 8 years after the identification of the first miRNA in 1993, and since then, there has been a significant increase in miRNA-related research and discoveries. MiRNAs have been implicated in various biological processes, including cancer, particularly in colorectal cancer (CRC). In CRC, miRNAs act as either oncogenes or tumor suppressors, influencing essential cellular functions such as cell proliferation, apoptosis, angiogenesis, and metastasis. The dysregulation of miRNAs in CRC can arise from different factors, leading to abnormal expression levels of their target mRNAs and subsequently affecting protein production. Consequently, miRNAs may directly target oncogenes or tumor suppressor genes, thereby contributing to cancer initiation and progression. Notably, tumors often exhibit reduced expression of mature miRNAs. In CRC research, miRNAs offer potential as diagnostic biomarkers and therapeutic targets. Specific miRNA profiles could serve as non-invasive tools for early CRC detection and risk assessment. Additionally, miRNA-based therapies present a promising approach for targeted cancer treatment by modulating miRNA expression. However, challenges related to delivery systems and long-term safety must be addressed to fully harness their therapeutic potential.

Identification of a novel CNV at the APC gene in a Chinese family with familial adenomatous polyposis

Introduction: Familial adenomatous polyposis (FAP) is the second most commonly inherited colorectal cancer (CRC) predisposition caused by germline mutations within the adenomatous polyposis coli (APC) gene. The molecular defects and clinical manifestations of two FAP families were analyzed, and individual prevention strategies suitable for mutation carriers in different families were proposed. Methods and results: The pathogenic gene mutations were identified among the two families using whole-exome sequencing and verified with Sanger sequencing or quantitative polymerase chain reaction (qPCR). One novel (GRCh37:Chr5: 112145676-112174368, del, 28,692 bp) and a known (c.C847T:p.R283X) mutation in the APC gene were pathogenic mutations for FAP, according to the sequencing data and tumorigenesis pattern among the family members. The two mutations led to a premature translational stop signal, synthesizing an absent or disrupted protein product. Conclusion: Our findings expand the known germline mutation spectrum of the APC gene among the Chinese population. This reaffirms the importance of genetic testing in FAP. Genetic consultation and regular follow-ups are necessary for the individualized treatment of cancer-afflicted families with APC expression deficiency. Additional work is required to develop safe and effective chemotherapy and immunotherapy for FAP based on the mutation type.

Increased prevalence of the founder BRCA1 c.5309G>T and recurrent BRCA2 c.1310_1313delAAGA mutations in breast cancer families from Northerstern region of Morocco: evidence of geographical specificity and high relevance for genetic counseling

BACKGROUND

Inherited mutations in the breast cancer susceptibility genes BRCA1 and BRCA2 (BRCA1/2) confer high risks of breast and ovarian cancer. Because the contribution of BRCA1/2 germline mutations to BC in the Northeastern population of Morocco remains largely unknown, we conducted this first study to evaluate the prevalence and the phenotypic spectrum of two BRCA1/2 pathogenic mutations (the founder BRCA1 c.5309G>T and BRCA2 c.1310_1313delAAGA). This choice was also argued by the presence of an apparent specific geographical connection of these mutations and the Northeastern region of Morocco.

METHODS

Screening for the germline mutations c.5309G>T and BRCA2 c.1310_1313delAAGA was performed by sequencing on a total of 184 breast cancer (BC) patients originated from the Northeastern region of Morocco. The likelihood of identifying a BRCA mutation is calculated using the Eisinger scoring model. The clinical and pathologic features were compared between the BRCA-positive and BRCA-negative groups of patients. Difference in survival outcomes was compared between mutation carriers and non-carriers.

RESULTS

BRCA1 c.5309G>T and BRCA2 c.1310_1313delAAGA are responsible for a significant proportion of all BC cases (12.5%) and at least 20% of familial BC. The screening of BRCA1/2 genes by NGS sequencing confirmed that there are no additional mutations detected among positive patients. The clinicopathological features in positive patients were in accordance with typical characteristics of BRCA pathogenic mutations. The mean features in the carriers were the early onset of the disease, familial history, triple negative status (for BRCA1 c.5309G>T) and worse prognosis in terms of overall surviving. Our study indicates that the Eisinger scoring model could be recommended to identify patients for referral to BRCA1/2 oncogenetic counseling.

CONCLUSION

Our findings suggest that BRCA1 c.5309G>T and BRCA2 c.1310_1313delAAGA mutations may have a strong founder and/or recurrent effect on breast cancer among the Northeastern Moroccan population. There contribution to breast cancer incidence is certainly substantial in this subgroup. Therefore, we believe that BRCA1 c.5309G>T and BRCA2 c.1310_1313delAAGA mutations have to be included in the array of tests aimed at revealing cancer syndrome carriers among subjects of Moroccan origin.

Approach to Familial Predisposition to Colorectal Cancer

The traditional approach of one-size-fits-all for colorectal cancer has been replaced by personalized interventions to an individual's unique genetic, molecular, and environmental profile, seeking to identify high-risk individuals who would benefit from individualized screening and surveillance. This change in approach is due, in part, to emerging technologies, such as next-generation DNA sequencing.

Disparities in Cancer Genetic Testing and Variants of Uncertain Significance in the Hispanic Population of South Texas

PURPOSE

Racial and ethnic disparities have included a lack of access to both genetic testing and research, resulting in poor understanding of the genomic architecture in under-represented populations. The South Texas population is primarily of Hispanic background and has been largely devoid of genetic services. We extended access to this underserved population and uncovered genetic variants previously not observed, emphasizing the need to continually improve both genomic databases and clarification of variant significance to provide meaningful patient counseling.

METHODS

This study consisted of a retrospective cohort review of patients seen through a cancer genetics education and service program across 24 counties in South Texas. In total, 1,595 individuals were identified as appropriate for cancer genetic counseling and 1,377 completed genetic testing.

RESULTS

Eighty percent of those receiving genetic counseling self-identified as Hispanic, 16% as non-Hispanic White (NHW), 3% as African American, and 1% as other race/ethnicity. Of reported variants, 18.8% were pathogenic and 13.7% were reported as a variant of uncertain significance (VUS). VUS was reported in 17.2% of the Hispanic individuals compared with 9% NHW (P = .005).

CONCLUSION

Individuals of Hispanic ethnicity were significantly more likely to harbor a VUS compared with NHW. The extended reach into our regional communities revealed a gap in the ability to accurately interpret genomic variation with implications for advising patients on screening, prevention, and management strategies. A higher percentage of VUS also emphasizes the challenge of continued follow-up amid existing barriers that led to disparities in access. As understanding of the variants develops, hopefully gaps in knowledge of the genomic landscape will be lessened with increased clarity to provide accurate cancer risk assessment and recommendations for implementing prevention initiatives.

Germline mutations of the adenomatous polyposis coli (APC) gene in Algerian familial adenomatous polyposis cohort: first report

BACKGROUND

Familial adenomatous polyposis (known also as classical or severe FAP) is a rare autosomal dominant colorectal cancer predisposition syndrome, characterized by the presence of hundreds to thousands of adenomatous polyps in the colon and rectum from an early age. In the absence of prophylactic surgery, colorectal cancer (CRC) is the inevitable consequence of FAP. The vast majority of FAP is caused by germline mutations in the adenomatous polyposis coli (APC) tumor suppressor gene (5q21). To date, most of the germline mutations in classical FAP result in truncation of the APC protein and 60% are mainly located within exon 15.

MATERIAL AND METHODS

In this first nationwide study, we investigated the clinical and genetic features of 52 unrelated Algerian FAP families. We screened by PCR-direct sequencing the entire exon 15 of APC gene in 50 families and two families have been analyzed by NGS using a cancer panel of 30 hereditary cancer genes.

RESULTS

Among 52 FAP index cases, 36 had 100 or more than 100 polyps, 37 had strong family history of FAP, 5 developed desmoids tumors, 15 had extra colonic manifestations and 21 had colorectal cancer. We detected 13 distinct germline mutations in 17 FAP families. Interestingly, 4 novel APC germline pathogenic variants never described before have been identified in our study.

CONCLUSIONS

The accumulating knowledge about the prevalence and nature of APC variants in Algerian population will contribute in the near future to the implementation of genetic testing and counseling for FAP patients.

Identification of Eleven Novel BRCA Mutations in Tunisia: Impact on the Clinical Management of BRCA Related Cancers

Background

Breast cancer is the world's most common cancer among women. It is becoming an increasingly urgent problem in low- and middle-income countries (LMICs) where a large fraction of women is diagnosed with advanced-stage disease and have no access to treatment or basic palliative care. About 5-10% of all breast cancers can be attributed to hereditary genetic components and up to 25% of familial cases are due to mutations in BRCA1/2 genes. Since their discovery in 1994 and 1995, as few as 18 mutations have been identified in BRCA genes in the Tunisian population. The aim of this study is to identify additional BRCA mutations, to estimate their contribution to the hereditary breast and ovarian cancers in Tunisia and to investigate the clinicopathological signatures associated with BRCA mutations.

Methods

A total of 354 patients diagnosed with breast and ovarian cancers, including 5 male breast cancer cases, have been investigated for BRCA1/2 mutations using traditional and/or next generation sequencing technologies. Clinicopathological signatures associated with BRCA mutations have also been investigated.

Results

In the current study, 16 distinct mutations were detected: 10 in BRCA1 and 6 in BRCA2, of which 11 are described for the first time in Tunisia including 3 variations that have not been reported previously in public databases namely BRCA1_c.915T>A; BRCA2_c.-227-?_7805+? and BRCA2_c.249delG. Early age at onset, family history of ovarian cancer and high tumor grade were significantly associated with BRCA status. BRCA1 carriers were more likely to be triple negative breast cancer compared to BRCA2 carriers. A relatively high frequency of contralateral breast cancer and ovarian cancer occurrence was observed among BRCA carriers and was more frequent in patients carrying BRCA1 mutations.

Conclusion

Our study provides new insights into breast and ovarian cancer genetic landscape in the under-represented North African populations. The prevalence assessment of novel and recurrent BRCA1/2 pathogenic mutations will enhance the use of personalized treatment and precise screening strategies by both affected and unaffected North African cancer cases.

Cancer genetic testing in marginalized groups during an era of evolving healthcare reform

BACKGROUND

The Affordable Care Act and subsequent reforms pose tradeoffs for racial-ethnic, rural, and sex-related groups in the United States experiencing disparities in BRCA1/2 genetic counseling and testing and colorectal cancer screening, calling for policy changes.

METHODS

A working group of the American Public Health Association Genomics Forum Policy Committee engaged in monthly meetings to examine ongoing literature and identify policy alternatives in the coverage of cancer genetic services for marginalized groups. 589 items were collected; 408 examined. Efforts continued from February 2015 through September 2020.

RESULTS

African Americans and Latinos have shown 7-8 % drops in uninsured rates since the Exchanges opened. The ACA has increased BRCA1/2 test availability while several disparities remain, including by sex. Rural testing and screening utilization rates have improved. Medicaid expansion and the inclusion of Medicare in the ACA have resulted in mixed improvements in colorectal cancer screening rates in marginalized groups.

CONCLUSION

Cancer genetic testing and screening to date have only partially benefited from healthcare reforms. Sensitivity to cost concerns and further monitoring of emerging data are needed. A reduction in disparities depends on the availability of private insurance, Medicaid and Medicare to the marginalized. Attention to value-based design and the way cancer benefits are translated into actual testing and screening are crucial.

POLICY SUMMARY

The findings suggest the need for further benefits-related health agency interpretation of and amendments to the ACA, continued Medicaid and innovative Medicare expansion, and incorporation of cancer services values-based considerations at several levels, aimed at reducing group disparities.

Breast Cancer Health Disparities in Hispanics/Latinas

Purpose of the review

Breast cancer incidence and mortality rates are lower in some Hispanic/Latino subpopulations compared to Non-Hispanic White women. However, studies suggest that the risk of breast cancer-specific mortality is higher in US Hispanics/Latinas. In this review we summarized current knowledge on factors associated with breast cancer incidence and risk of mortality in women of Hispanic/Latino origin.

Recent findings

Associative studies have proposed a multiplicity of factors likely contributing to differences in breast cancer incidence and survival between population groups, including socioeconomic/sociodemographic factors, lifestyle choices as well as access to and quality of care. Reports of association between global genetic ancestry overall as well as subtype-specific breast cancer risk among Hispanic/Latinas suggest that incidence and subtype distribution could result from differential exposure to environmental and lifestyle related factors correlated with genetic ancestry as well as germline genetic variation.

Summary

Hispanic/Latino in the United States have been largely underrepresented in cancer research. It is important to implement inclusive programs that facilitate the access of this population to health services and that also include education programs for the community on the importance of screening. In addition, it is important to continue promoting the inclusion of Hispanics/Latinos in genomic studies that allow understanding the biological behavior of this disease in the context of all human genetic diversity.

Genetics and Genomics of Breast Cancer: update and translational perspectives

In the recent years the rapid scientific innovation in the evaluation of the individual's genome have allowed the identification of variants associated with the onset, treatment and prognosis of various pathologies including cancer, and with a potential impact in the assessment of therapy responses. Despite the analysis and interpretation of genomic information is considered incomplete, in many cases the identification of specific genomic profile has allowed the stratification of subgroups of patients characterized by a better response to drug therapies. Individual genome analysis has changed profoundly the diagnostic and therapeutic approach of breast cancer in the last 15 years by identifying selective molecular lesions that drive the development of neoplasms, showing that each tumor has its own genomic signature, with some specific features and some features common to several sub-types. Several personalized therapies have been (and still are being) developed showing a remarkable efficacy in the treatment of breast cancer.

Education on cancer risk assessment and genetic counseling to address cancer health disparities among racial/ethnic groups and rural populations: Implementing culturally tailored outreach through community health educators

While significant progress is being made in cancer prevention and treatment, opportunity exists to make a difference for populations bearing an uneven burden of the disease. Research indicates that increased inherited risk and more-aggressive forms of cancer among underserved racial/ethnic (R/E) groups (e.g., African American/Black, American Indian/Alaska Native, Asian, Hispanic/Latino, and Native Hawaiian/Other Pacific Islander) and rural populations may explain the cancer incidence and mortality disparities these populations experience. These racial and ethnic (R/E) categories reflect the standard naming convention for the classification of federal data on race and ethnicity. One method by which progress can be made for these underserved populations is to expand knowledge of, access to, and uptake of two existing and impactful preventive oncology tools-cancer screening and genetic counseling and risk assessment (GCRA). Individuals from these populations who have cancer may benefit by learning about treatment options, risk projections for secondary cancers, and clinical trial participation. Effecting change in community beliefs and behaviors regarding these preventive tools and yielding the aforementioned benefits will see greater success if shepherded by individuals accepted and trusted in the respective communities. This was the charge taken on and embraced by Community Health Educators in the National Cancer Institute (NCI) Center to Reduce Cancer Health Disparities' (CRCHD) National Outreach Network (NON) and U54 Comprehensive Partnerships to Advance Cancer Health Equity (CPACHE) programs. The NCI CRCHD integrated into the work of these CHEs an emphasis on cancer genetic education. As part of their undertaking, NON and CPACHE CHEs detail education and outreach strategies that may be helpful to increase GCRA awareness and uptake in R/E groups and rural populations and, in turn, bring positive change for those with or at risk for heritable cancers.

Clinical characterization and mutation spectrum in patients with familial adenomatous polyposis in China

BACKGROUND AND AIM

Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. Patients with FAP are screened for germline mutations of two genes, APC and MUTYH. However, limited data exist on the clinical characterization and genotypic spectrum of FAP in China. This study was aimed to determine APC and MUTYH mutational status in a small cohort of FAP probands in China and to characterize the genotype-phenotype correlation in mutated patients.

METHODS

Mutation screening of 46 unrelated probands was performed using multigene panels by next-generation sequencing. Clinical data of the index were used to assess genotype-phenotype correlations.

RESULTS

Overall, 42 out of 46 (91.30%) unrelated probands found mutations, including 35 (76.09%) with APC mutations, 3 (6.52%) with MUTYH mutations, and 4 (8.70%) with both APC and MUTYH mutations. Ten APC genetic alterations variants were novel. The hereditary pattern of the family with both APC and MUTYH mutations was autosomal dominant inheritance. Upper gastrointestinal polyp was the most common extracolonic manifestations. The onset time for patients with both APC and MUTYH mutations was earlier than MUTYH mutation carriers and similar to APC mutation carriers. But the age of carcinogenesis for patients with both APC and MUTYH mutations was later than APC mutation carriers and similar to MUTYH mutation carriers.

CONCLUSION

In this study, we show the importance of using multigene panels that allow for a parallel comprehensive screening. We suggest that genetic testing of patients with suspected adenomatous polyposis syndromes should include APC and MUTYH gene mutation analyses simultaneously.

Colorectal cancer knowledge and screening adherence among low-income Hispanic employees

Hispanics have the lowest colorectal cancer (CRC) screening rates of all racial/ethnic groups and comprise the largest proportion of low-income manual laborers in the nation. We partnered with businesses to implement a community health worker (CHW)-led intervention among Hispanic workers in service-related and manual labor occupations, which often pay low wages and do not provide health insurance. CHWs measured knowledge, screening adherence and perceptions of CRC risk before and after educational interventions via interview. CHWs provided fecal immunochemical tests (FITs) to participants aged ≥50 years. Chi-square tests and logistic regression identified pre-intervention predictors of CRC knowledge of all participants and adherence among eligible participants. Adherence among participants increased from 40% (n = 307) pre-intervention to 66% post-intervention. Knowledge about CRC was associated with age ≥50 years (OR = 8.90 [95% CI = 2.61-30.35]; ref = 18-30) and perceived personal risk for CRC (Likely, OR = 3.06 [95% CI = 1.40-6.67]; ref = Not likely). Insurance status was associated with screening adherence pre-intervention (OR = 3.00 [95% CI 1.10-8.12]; ref = No insurance). Improvement in adherence post-intervention was associated with income between $25 000 and ≥$55 000 (OR = 8.49 [95% CI 1.49-48.32]; ref = $5000-<$10 000). Community-based health programs can improve CRC screening adherence among Hispanic workers in service-related and manual labor positions, but lowest-income workers may need additional support.

Association of genetic ancestry with colorectal tumor location in Puerto Rican Latinos

Background

Colorectal cancer (CRC) is the first cause of cancer deaths among Puerto Ricans. The incidence and mortality of CRC in Puerto Rico continue to be on the rise. The burden of CRC in Puerto Rico is higher than among US Hispanics and is second only to African Americans, thus supporting the importance of studying this CRC health disparity. The genetic background of the Puerto Rican population is a mix of European, African, and Amerindian races, which may account, in part, for the differences observed in the CRC mortality rates among Puerto Ricans. The objective of the study was to assess the role of genetic ancestry in CRC risk and its association with clinicopathological features of CRC tumors in Puerto Ricans.

Results

We used a validated panel of 105 ancestry informative markers (AIMs) to estimate genetic ancestry in 406 Puerto Rican CRC cases and 425 Puerto Rican controls. We examined the association of genetic ancestry with CRC risk and tumor clinicopathological characteristics.

Conclusions

The mean ancestry proportions in the study population were 61% European, 21% African, and 18% Amerindian. No association was observed between genetic ancestry and risk of CRC. However, African ancestry was associated with an increased risk of developing rectal tumors (OR = 1.55, 95% CI 1.04–2.31). Additional studies are needed to fully elucidate the role of African ancestry in CRC carcinogenesis.

Frequency of Mismatch Repair Protein Deficiency in a Puerto Rican Population with Colonic Adenoma and Adenocarcinoma

BACKGROUND/AIM

Microsatellite instability (MSI) results from genetic alterations involving the mismatch repair (MMR) genes MLH1, PSM2, MSH2, and MSH6. MSI has been implicated in both sporadic CRC and Lynch syndrome. The aim of the study was to assess the frequency of alterations in MMR protein expression in both primary colorectal cancer and precursor lesions among Puerto Rican patients.

PATIENTS AND METHODS

A retrospective study of 84 Puerto Rican patients was performed to assess the frequency of MMR protein expression alterations in both primary CRC and precursor lesions using tissue microarray and immunohistochemistry.

RESULTS

The loss of expression of both MLH1 and PMS2 proteins was present in 6.3% of adenomas, 9.1% of adenomas with high-grade dysplasia and 9.4% of colon adenocarcinomas. Negative nuclear staining for both MSH2 and MSH6 proteins was found in 2.4% of colon adenocarcinomas.

CONCLUSION

When compared to prior reports, this study suggests a lower frequency of MSI among the Puerto Rican population. The higher prevalence of MLH1 mutations correlates with previous studies of protein expression among the Hispanic community including Colombian, Uruguay and Brazilian populations.

Identification of a mutL‑homolog 1 mutation via whole‑exome sequencing in a Chinese family with Gardner syndrome

Gardner syndrome (GS), a variant of familial adenomatous polyposis, is a rare genetic disorder with autosomal dominant inheritance, characterized by the presence of multiple intestinal polyps, multiple osteomas, dental abnormalities and soft tissue tumors. To date, only a few gene mutations have been demonstrated to be responsible for GS. To explore potential unknown mutations responsible for GS, the present study used whole‑exome sequencing of two affected individuals from a family with GS to identify a candidate mutation in mutL‑homolog (MLH)1. The two patients with GS were diagnosed based on a combination of clinical features, family history, physical examinations and cone‑beam computed tomographic imaging. Through whole‑genome sequencing, the present study subsequently identified a missense mutation in MLH1 (NM_000249.3:p.Tyr379Ser/c.1136A>C), which was further confirmed by Sanger sequencing. Furthermore, the amino acid residue p.Tyr379 was identified to be highly conserved among different species through sequence alignment with ClustalW2. In conclusion, the results identified for the first time a MLH1 missense mutation (NM_000249.3:​p.Tyr379Ser/c.1136A>C) in a Chinese family with GS, thus broadening the range of mutated genes associated with GS. This highlights the value of whole‑exome sequencing in identifying disease mutations in a family.

Breast Cancer Incidence and Risk Reduction in the Hispanic Population

Breast cancer is the most common non-skin cancer amongst women worldwide and is the fifth leading cause of cancer-related mortality overall. It is also the foremost reason for cancer-related mortality in Hispanic females in the United States (US). Although the current incidence of breast cancer is significantly lower in Hispanics compared to that of non-Hispanic Whites (NHW) and Blacks, (91.9, 128.1, and 124.3 per 100,000, respectively, annually), this may increase if Hispanics develop similar lifestyle behaviors to other American women, in categories such as weight management, age at first birth, number of children, and breastfeeding habits. Stage-for-stage mortality for Hispanics is similar to NHWs, but the mortality rate is not declining as rapidly in this ethnic group. Hispanic women share many of the same risk factors for developing breast cancer as NHWs and Blacks. This suggests that many of the risk reduction strategies used in other racial populations may also benefit this group. Providing education about breast cancer and implementing risk reduction strategies in culturally-aware environments could help keep incidence low and reduce cancer-related mortality. Since Hispanics are the largest minority group in the US, this could have a significant impact on the incidence and mortality nationally.

Breast cancer genetics in young women: What do we know?

Breast cancer (BC) in young women, generally defined in oncology as women who are 40 years of age or younger, represents 2 out of 10 BC cases in developing countries. Several research studies, including genetic cancer panel tests, genome-wide association studies, expression analyses and polymorphisms reports, have found that young women with BC exhibit a higher genetic susceptibility and specific genomic signature compared to postmenopausal women with BC. Thus, international guidelines recommend genetic counseling for this age population. This review presents the current state of the art of genetics and genomics with regards to young women with BC.

Hereditary factors are unlikely behind unusual pattern of early - Onset colorectal cancer in Egyptians: A study of family history and pathology features in Egyptians with large bowel cancer (cross-sectional study)

BACKGROUND

Colorectal cancer in Egypt has a higher incidence in young patients compared to western countries, where the disease is more prevalent in the old age group. This difference has been attributed to higher incidence of hereditary cancers in young Egyptian patients. The aim of this study is to compare the family history criteria and pathology features of tumors in young (≤40 years) and old (>40 years) Egyptian patients with adenocarcinoma of the colon and rectum.

MATERIALS AND METHODS

This is the analysis of our prospectively collected data on the pathology features of tumors in 313 consecutive patients (133 young, 180 old) with colorectal cancer presenting to the Department of Surgery within an eight-year period. A detailed family history was obtained from 258 patients (112 young, 146 old).

RESULTS

41 young and 48 old patients reported family history of cancer, the difference was not statistically significant. Ten young patients (9%) reported a family history of colorectal cancer in a first degree relative (3 fitting into Amsterdam criteria, 7 fitting into less strict criteria) which was not significantly different from the old age group. The pathologic features of tumors in both groups resembled sporadic rather than hereditary cancer and there was no significant difference between groups in tumor location, degree of differentiation, mucin production, synchronous and metachronous colorectal tumors or polyps and grossly stricturing or ulcerating tumors. Extracolonic tumors developed in one young and two old patients.

CONCLUSION

The characteristics of large bowel cancer in young Egyptian patients do not differ significantly from those in older patients. Despite the high incidence of large bowel cancer in young Egyptian patients, family history and pathologic features of tumors do not support a hereditary origin of colorectal cancer in this age group in Egypt.