Definition

Lynch syndrome is a hereditary genetic disorder that increases the risk of developing cancer at a later stage of life. HNPCC, sometimes referred to as Hereditary Nonpolyp Colorectal Cancer, is the predominant hereditary variant of colorectal (colon) cancer.

This terminology is used to describe families with a very strong history of colon cancer. Doctors commonly discover the presence of an inherited gene within a family responsible for cancer development. Due to its heredity, this condition is transmitted from parents to children. During pregnancy, genetic mutations are inherited.

People who are diagnosed with this syndrome are at higher risk of developing cancer before age 50. Data from the United States indicates that Lynch syndrome affects 1 in every 279 individuals. Lynch syndrome is associated with an increased risk of developing various types of cancer, including colon cancer and uterine cancer (endometrium). An estimated 4,000 cases of colorectal cancer and 1800 cases of endometrial cancer are diagnosed annually as a result of Lynch syndrome.

We have a colorectal cancer article that you can read here.

Causes

Lynch syndrome results from a hereditary genetic mutation transmitted from parents to children. DNA, a collection of genetic material that encodes instructions for all chemical processes in the body, consists of genes. This disruptive DNA is capable of inducing a variety of somatic disorders.

Mutations manifest in genes that correct defects during DNA replication, specifically the MLHL, MSH2, MSH6, PMS2, and EPCAM genes, in individuals with Lynch syndrome. Due to genomic mutations, DNA copies may contain several defects. The injured cells cannot be removed; instead, they proliferate, resulting in cancer.

Lynch syndrome is inherited as autosomal dominant, indicating that if one parent has the gene mutation that causes Lynch syndrome, the child has a 50% chance of inheriting the same mutation.

Risk factor

The family history of Lynch syndrome is the most significant risk factor. People with specific cancers, especially at a younger age, are also at higher risk. Children have a fifty percent probability of inheriting Lynch syndrome from parents with similar conditions.

Symptoms

The symptoms of Lynch syndrome may vary among individuals due to its severity. The following symptoms are most frequently observed in individuals with colorectal cancer:

• Changes in faecal size and blood in the feces
• Chronic constipation
• Abdominal pain or cramps
• Excessive fullness and bloating
• Nausea or vomiting
• Diarrhea
• Fatigue
• Weight loss for no apparent reason

Not everyone will experience symptoms of malignancy until it has advanced. If you experience any of these symptoms, please consult a doctor.

Diagnosis

Typically, patients seek medical attention at a health center only when encountering several medical problems. The doctor will inquire extensively regarding the following:

• Age
• Chief and additional complaints
• Medical history
• Familial predisposition, particularly the cancer history
• Lifestyle, physical activity, and dietary intake

Following that, the doctor may conduct a comprehensive physical assessment by evaluating essential indicators such as blood pressure, pulse rate, body temperature, and respiratory rate. 

Further examinations include genomic, blood, and urine analyses. Lynch syndrome is confirmed through tumor screening or genomic analysis.

• Genomic test

Your doctor might advise that you undergo genetic testing for certain genes that have been related to the disorder. Genetic testing may produce the following results:

Positive: The presence of the Lynch syndrome-associated mutation is indicated if the genetic variant is detected.

Negative: In this case, the Lynch syndrome-causing genetic variant has not been identified.

Variant of Unknown Significance (VUS): The causal relationship between a genetic mutation identified in one of the genes associated with Lynch syndrome and the growth of cancer remains uncertain.

• Tumor screening

Upon diagnosis of colorectal or endometrial cancer, the tissue of the tumor is typically analyzed to figure out whether Lynch syndrome could be the underlying cause.

Based on the severity of the symptoms, doctors may also perform further examinations, such as an ultrasound, endoscopy, or biopsy.

Management

A curative medication for this condition remains unknown. Individuals diagnosed with Lynch syndrome are frequently screened for early-stage malignancies. The probability of successful treatment increases when cancer is detected in its early stages. Cancer may be prevented through the surgical removal of certain organs before the malignant transformation. The immune system and the severity of their symptoms may determine the patient’s outcome.

It is strongly recommended that patients see medical professionals for an accurate diagnosis. Doctors from different backgrounds will collaborate to treat Lynch syndrome due to its effects on several organs and systems. An increased risk of cancer recurrence following surgical removal is associated with the genetic characteristics of the disease.

Due to an increased risk of cancer, individuals with Lynch syndrome may receive surgical procedures such as a hysterectomy (removal of the uterus), an oophorectomy (removal of ovaries), or a colectomy (removal of the intestine).

Complications

The diagnosis of Lynch syndrome may lead to several concerns regarding health and complications, including:

• Privacy

You might be concerned about the potential impacts on your company or insurance provider. A genetics expert may provide guidance on legal protections.

• Hereditary

The children of an individual with Lynch syndrome are at risk of inheriting a similar condition. The doctor may help you develop a strategy to explain this to your children. It may specify when and how to notify them and when they need to consider conducting an examination.

Most significantly, malignancy is an absolute complication of Lynch syndrome. Inadequate treatment of the malignancy may result in a decrease in quality of life or mortality.

Prevention

Since Lynch syndrome is a hereditary condition, it is not preventable. Patients with Lynch syndrome are advised to start lifelong cancer screening to detect the disease earlier. Nevertheless, maintaining a healthy lifestyle through adequate sleep and nutritious foods is strongly recommended.

When to see a doctor?

Everyone with Lynch syndrome should visit the doctor once a year for general checkups. It may help set up regular screenings to identify cancer in its early stages.

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