When it comes to understanding Lynch syndrome and its associated medical terms, it can feel like learning a new language. We’re here to empower you with a list of these terms and their definitions, so you and your family can navigate the complexities of this condition with confidence and clarity.
Many of us have experienced the frustration of sitting in a doctor’s office, hearing terms we don’t fully grasp, and feeling unable to ask crucial questions about our health.
To empower you and your family, we’ve compiled a list of key terms related to Lynch syndrome. By the end of this blog, you’ll have a clearer understanding of these terms so you can navigate discussions and take proactive steps for your health and your family’s well-being.
#1 – Assay
An assay is a laboratory procedure used to measure the presence, amount, or activity of a specific substance, such as a chemical compound, enzyme, or biological marker, in a sample. Assays can be performed on various sample types, including blood, urine, tissues, or other biological materials, and help healthcare professionals make informed decisions based on the results.
#2 – Autosomal dominance
Autosomal dominance refers to the way Lynch syndrome is inherited. Only one copy of a mutated gene (passed down from one parent) is necessary to cause the condition. So, if one parent carries a gene mutation associated with Lynch syndrome, there’s a 50% chance that their children will inherit the same mutation.
#3 – Cancer surveillance
Cancer surveillance refers to the regular screenings and check-ups designed to catch cancer early or identify opportunities to prevent it altogether.
For individuals with Lynch syndrome, cancer surveillance may include frequent colonoscopies, endometrial biopsies, or even imaging of other organs to monitor for early signs of cancer. By staying vigilant, individuals with Lynch syndrome can detect cancer in its early stages, when it is most treatable.
#4 – DiagMMR
Lynsight’s DiagMMR assay detects mismatch repair (MMR) deficiency using a minimally invasive, non-malignant tissue sample. This allows for early detection of Lynch syndrome-related risks before tumors develop. Unlike traditional Lynch syndrome tests, which rely on DNA sequencing, DiagMMR analyzes proteins directly from patient cells, delivering results in 4 weeks without the need for variant interpretation.
For 10 years, Lynsight has been working on perfecting DiagMMR and is now focused on making it available globally. Consult with your treatment team to see if Lynsight’s DiagMMR is available where you are.
#5 – DNA sequencing
DNA sequencing is a traditional laboratory method used to determine the order of nucleotides (the building blocks of DNA) in a person’s genetic code. This technique helps identify mutations in specific genes related to Lynch syndrome. While DNA sequencing can be a powerful tool for diagnosing genetic conditions and understanding a person’s cancer risk, it also has limitations.
DNA sequencing requires identifying the specific genetic variant or mutation, which can be time-consuming and requires additional clinical data that may not always be available. In some cases, DNA sequencing may detect variants of uncertain significance, which means the results are ambiguous and do not provide clear answers about cancer risk. Additionally, DNA sequencing may miss mutations in regions of the genome that are difficult to sequence or interpret, limiting its ability to detect all potential risk factors.
#6 – EPCAM, MLH1, MSH2, MSH6, and PMS2 genes
These five genes are essential in understanding and managing Lynch syndrome. Mutations in any one of them can lead to the development of the condition. Here’s a breakdown:
- MLH1, MSH2, MSH6, and PMS2: These genes are part of the body’s MMR system, responsible for fixing errors that occur when DNA is copied in cells. Mutations in these genes disrupt the MMR system, leading to an increased risk of cancer.
- EPCAM: Although EPCAM isn’t part of the MMR system itself, deletions in this gene can inactivate MSH2, indirectly contributing to Lynch syndrome.
#7 – Genetic predisposition
A genetic predisposition means that a person has inherited genetic factors that increase their risk of developing a disease. In the case of Lynch syndrome, individuals with mutations in the aforementioned genes have a genetic predisposition to several types of cancer, most commonly colorectal, endometrial, and ovarian cancers.
#8 – Immunohistochemistry (IHC)
IHC is a laboratory technique used to detect specific proteins in tumor tissue samples. It’s often used to check for the presence or absence of mismatch repair (MMR) proteins, helping to identify potential deficiencies that may indicate Lynch syndrome. This method aids in determining whether further genetic testing is needed.
#9 – Inconclusive test results
Inconclusive test results refer to outcomes from genetic testing or medical examinations that do not provide clear or definitive information about a diagnosis or condition. In the context of Lynch syndrome, these results indicate that the test did not identify a specific mutation associated with the condition, nor did it rule it out. This uncertainty can arise from various factors, such as insufficient genetic material or ambiguous findings, such as a VUS, making it challenging for healthcare providers to determine appropriate next steps.
#10 – Mismatch repair (MMR)
The mismatch repair (MMR) system is one of the body’s essential mechanisms for correcting errors that arise when DNA replicates during cell division. When this system is faulty due to mutations in genes like MLH1, MSH2, MSH6, or PMS2, DNA errors accumulate, leading to increased cancer risk. Identifying defects in MMR is one of the key ways doctors diagnose Lynch syndrome.
#11 – Polyps
Polyps are growths that form in the lining of organs like the colon or uterus. While most polyps are benign (non-cancerous), those associated with Lynch syndrome may have a higher risk of becoming cancerous. Regular screening and polyp removal are important for people with Lynch syndrome to reduce the risk of developing colorectal cancer.
#12 – Prophylactic surgery
Prophylactic surgery – also known as preventative surgery – involves the removal of organs or tissues that have a high risk of developing cancer. In Lynch syndrome, this may involve procedures like colectomy (removal of part or all of the colon) or hysterectomy (removal of the uterus) in women with an elevated risk of uterine cancer.
#13 – Variant of uncertain significance (VUS)
VUS is a genetic alteration discovered during testing that has unclear implications for disease risk. In Lynch syndrome, a VUS in one of the related genes (such as MLH1, MSH2, MSH6, PMS2, or EPCAM) means that its impact on increasing cancer risk is not yet fully understood, making it difficult to provide definitive answers about a patient’s risk of developing cancer.
Conclusion
Lynch syndrome can be overwhelming, but understanding its terminology can help demystify this genetic condition and what it means in real life for you and your family. Whether you’re navigating the risk of cancer for yourself or supporting a loved one, knowing these terms can help guide conversations with healthcare providers and empower you to make informed decisions.
At Lynsight, we’re here to support you every step of the way. Our accurate and comprehensive Lynch syndrome testing helps you understand your genetic risks and empowers you to make informed decisions about your health. Get more resources for you and your family here.