Expert Reviewed By: Dr. Brandon Colby MD
Colorectal cancer is the third most common cancer worldwide, affecting millions of people every year. While many cases are sporadic, meaning they occur without any known genetic predisposition, a significant proportion of cases are hereditary. One such hereditary form of colorectal cancer is non-polyposis colorectal cancer (NPCC), which can be further classified into Lynch syndrome and other forms of NPCC. In this article, we will explore the role of genetic testing in understanding, diagnosing, and managing non-polyposis colorectal cancer.
Understanding Non-Polyposis Colorectal Cancer
Non-polyposis colorectal cancer is a hereditary form of colorectal cancer that is characterized by the absence of numerous polyps in the colon. It is important to differentiate between Lynch syndrome, which is caused by mutations in specific mismatch repair genes, and other forms of NPCC that may be caused by different genetic mutations. Recent studies have shed light on the genetic basis of these conditions and have paved the way for the development of genetic testing strategies to identify at-risk individuals and guide clinical management.
A germline homozygous mutation in the base-excision repair gene NTHL1 causes adenomatous polyposis and colorectal cancer
This study identified a germline mutation in the NTHL1 gene as a cause of adenomatous polyposis and colorectal cancer. This finding has important implications for the diagnosis and management of NPCC, as it suggests that genetic testing for NTHL1 mutations may be useful in identifying individuals at risk for this condition.
Diagnosing Non-Polyposis Colorectal Cancer
Identifying individuals with hereditary non-polyposis colorectal cancer is crucial for early detection and prevention of cancer. Genetic testing plays a key role in the diagnostic process, allowing clinicians to identify mutations associated with NPCC and Lynch syndrome. Several approaches have been proposed to improve the cost-effectiveness and accuracy of genetic testing for these conditions.
Diagnostic application of hMLH1 methylation in hereditary non-polyposis colorectal cancer 1
This article proposes a cost-effective screening strategy for Lynch syndrome using methylation tests combined with microsatellite instability or pathological analysis. By implementing this approach, clinicians can more accurately diagnose Lynch syndrome and differentiate it from other forms of NPCC, allowing for tailored management strategies.
Using Genetic Testing to Guide Management of Non-Polyposis Colorectal Cancer
Once a diagnosis of NPCC or Lynch syndrome has been established, genetic testing can be used to guide clinical management, including cancer risk assessment, surveillance, and treatment. Understanding the specific genetic basis of an individual's condition can provide valuable information to inform these decisions.
Cancer risk and overall survival in mismatch repair proficient hereditary non-polyposis colorectal cancer, Lynch syndrome and sporadic colorectal cancer
This study compares clinical, morphological features, tumor KRAS status, and overall survival in mismatch repair proficient hereditary non-polyposis colorectal cancer (MSS-HNPCC), Lynch syndrome, and sporadic colorectal cancer. By understanding the differences between these conditions, clinicians can better tailor management strategies to the specific needs of each patient.
Lynch syndrome (hereditary non-polyposis colorectal cancer): Current concepts and approaches to management
This article discusses current concepts and management approaches for Lynch syndrome, a hereditary non-polyposis colorectal cancer. With advances in genetic testing and a growing understanding of the genetic basis of this condition, clinicians can better identify at-risk individuals and implement appropriate surveillance and treatment strategies to improve patient outcomes.
In conclusion, genetic testing plays a crucial role in understanding, diagnosing, and managing non-polyposis colorectal cancer. By identifying the specific genetic mutations associated with these conditions, clinicians can better tailor their approach to each patient, ultimately improving outcomes and reducing the burden of colorectal cancer.
About The Expert Reviewer
Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of and the author of Outsmart Your Genes.
Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC)