Comparison Between Familial Colorectal Cancer Type X and Lynch Syndrome: Molecular, Clinical, and Pathological Characteristics and Pedigrees

Risk for Hereditary Neoplastic Syndromes in Women with Mismatch Repair-Proficient Endometrial Cancer

Endometrial cancer (EC) is a prevalent malignancy in women, and those who are proficient in the DNA mismatch repair (pMMR) pathway may have a family history (FH) that meets the criteria for a hereditary neoplastic condition (HNS). This study aimed to estimate the risk of HNS in women with pMMR endometrial tumors by analyzing their FH. To achieve this, we collaborated with a primary study and collected FH information by telephone. The final sample comprised 42 women who responded to the Primary Screening Questionnaire. Their family pedigrees were drawn and categorized according to internationally standardized criteria for the risk of HNS. Results showed that 26 women (61%) were found to be at risk for HNS, with Bethesda criteria being met by 23%, Amsterdam criteria by 15%, and 4% met the attenuated familial adenomatous polyposis criteria. Our results emphasize the importance of FH and the need to encourage healthcare professionals to collect and document FH more frequently, even if it is self-reported. By identifying individuals with HNS, we can improve their outcomes and reduce the burden of cancer in families with a predisposition to cancer.

Preventive strategies in familial and hereditary colorectal cancer

Colorectal cancer is a leading cause of cancer-related deaths worldwide. While most cases are sporadic, a significant proportion of cases are associated with familial and hereditary syndromes. Individuals with a family history of colorectal cancer have an increased risk of developing the disease, and those with hereditary syndromes such as Lynch syndrome or familial adenomatous polyposis have a significantly higher risk. In these populations, preventive strategies are critical for reducing the incidence and mortality of colorectal cancer. This review provides an overview of current preventive strategies for individuals at increased risk of colorectal cancer due to familial or hereditary factors. The manuscript includes a discussion of risk assessment and genetic testing, highlighting the importance of identifying at-risk individuals and families. This review describes various preventive measures, including surveillance colonoscopy, chemoprevention, and prophylactic surgery, and their respective benefits and limitations. Together, this work highlights the importance of preventive strategies in familial and hereditary colorectal cancer.

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.

Hereditary Colorectal Cancer Syndromes: Molecular Genetics and Precision Medicine

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. Hereditary CRC syndromes account for approximately 5-10% of all CRC, with a lifetime risk of CRC that approaches 50-80% in the absence of endoscopic or surgical treatment. Hereditary CRC syndromes can be phenotypically divided into polyposis and non-polyposis syndrome, mainly according to the conditions of polyps. The typical representatives are familial adenomatous polyposis (FAP) and Lynch syndromes (LS), respectively. Over the past few decades, molecular genetics enhanced the discovery of cancer-predisposing genes and revolutionized the field of clinical oncology. Hereditary CRC syndromes have been a key part of this effort, with data showing that pathogenic variants are present in up to 10% of cases. Molecular phenotypes of tumors can not only help identify individuals with genetic susceptibility to CRC but also guide the precision prevention and treatment for the development of CRC. This review emphasizes the molecular basis and prevention strategies for hereditary CRC syndromes.

New insights on familial colorectal cancer type X syndrome

Familial colorectal cancer type X (FCCTX) is a heterogeneous colorectal cancer predisposition syndrome that, although displays a cancer pattern similar to Lynch syndrome, is mismatch repair proficient and does not exhibit microsatellite instability. Besides, its genetic etiology remains to be elucidated. In this study we performed germline exome sequencing of 39 cancer-affected patients from 34 families at risk for FCCTX. Variant classification followed the American College of Medical Genetics and Genomics (ACMG) guidelines. Pathogenic/likely pathogenic variants were identified in 17.65% of the families. Rare and potentially pathogenic alterations were identified in known hereditary cancer genes (CHEK2), in putative FCCTX candidate genes (OGG1 and FAN1) and in other cancer-related genes such as ATR, ASXL1, PARK2, SLX4 and TREX1. This study provides novel important clues that can contribute to the understanding of FCCTX genetic basis.