Muir Torre Syndrome

A rare genetic disorder that significantly increases the risk for multiple types of cancer is called Muir-Torre syndrome (MTS). Commonly, people with MTS develop skin tumors along with one or multiple tumors in the internal organs (in most cases, colorectal cancer).

In other words, MTS is characterized by malignant (cancerous) or benign (noncancerous) skin tumors that appear along with one or multiple internal cancers. Generally, there are about 200 cases of MTS. Most of them are among the white populations of Western nations. Furthermore, it also affects approximately 9% of people with HNPCC.

What Are The Symptoms of Muir-Torre Syndrome?

The primary symptoms of MTS are skin lesions and other cancer-related symptoms. Typically, these lesions appear before, with, or after cancerous tumors. While skin lesions appear quickly, cancer symptoms may appear over time. Check some types of skin lesions that often appear in people with MTS below:

Sebaceous adenomas – These are one of the most common skin lesions that appear in people with MTS. They appear in about 80% to 99% of people. Commonly, sebaceous adenomas are noncancerous, and they develop in the sebaceous glands. While they often develop on the head or neck, they may also appear on the trunk, including the pelvic area, back, chest, or abdomen.
Sebaceous carcinoma – This is a cancerous tumor that looks very similar to a sebaceous adenoma, but it frequently spreads quickly. In most cases, it develops on the eyelids and bleeds or secretes a crusty discharge.
Keratoacanthoma – This type of skin tumor appears in hair follicles on the head, neck, trunk, or arms. It can be cancerous or noncancerous and looks like a dome-shaped bump with visible blood vessels. Usually, this tumor grows quickly, but then it slowly diminishes over a few months or years. People with MTS may develop multiple keratoacanthomas.
Fordyce spots – Usually, MTS causes tumors in the sebaceous glands, but sometimes, doctors may look for ectopic sebaceous glands (also known as Fordyce spots) as a symptom. They often appear as enlarged and raised sebaceous glands in hairless areas on the skin (usually around the mouth). According to some research, Fordyce spots appear more commonly in people with MTS.

Causes

This is a genetic condition that occurs due to a mutation in one of your genes. The term “mutations” means changes to the DNA that occur during cell division when they make more copies of themselves. An abnormal DNA gives cells different instructions that cause them to reproduce without control. When these abnormal cells become too numerous, they form a mass called a tumor.

Most of the time, MTS is inherited from the biological parents during pregnancy. Approximately 60% of diagnosed cases are hereditary. However, not everyone who gets the abnormal gene is diagnosed with MTS. In rare cases, this syndrome occurs due to an original genetic mutation in people without a family history of the disease. Moreover, some people may have a mild MTS without any symptoms or knowledge of the condition. This form of the disease may become active when the immune system weakens. It often occurs in people who administer immunosuppressants or receive a solid organ transplant. However, there are other health conditions that can weaken your immune system.

Types of Muir-Torre Syndrome

Physicians have divided this disorder into 2 categories based on the gene mutation. For example:

Type 1 MTS – In such cases, MTS occurs due to a change (mutation) in one of the mismatch repair genes, which are responsible for fixing errors in the DNA. When it occurs, abnormal cells begin to build up in the tissues. While in 90% of cases there is a change in the MSH2 gene, a mutation in the MLH1, MSH6, and PMS2 genes could also play a role. Furthermore, this type of MTS occurs in an autosomal dominant pattern, which means only one abnormal gene that passes from biological parents to their biological children causes the disease. There is a 50% chance of getting the abnormal gene if only one parent has it.
Type 2 MTS – This type of MTS occurs due to a mutation in the MUTYH gene. It is responsible for repairing oxidative damage to the DNA. It occurs in about 30% of people with MTS. Abnormal cell production occurs when oxidation causes changes to the DNA. The second type of MTS is an autosomal recessive disorder, in which both parents have the same gene mutation.

How to Prevent Muir-Torre Syndrome?

Unfortunately, there is no way to prevent MTS because it is often present at birth. Moreover, physicians do not know what exactly causes genetic mutations that lead to MTS. In any case, you can perform some genetic tests before pregnancy to make sure you do not have any abnormal genes (including those that cause MTS) that could be passed to your children.

Diagnosis

When physicians suspect MTS, they will perform a physical examination to check for irregularities linked to the disease. They may also ask some questions about your family history and symptoms. However, to confirm or rule out MTS, physicians often perform genetic tests. They involve blood samples that are examined by doctors for the abnormal genes that cause MTS. Additionally, all people who develop MTS should have regular cancer screenings. These include:

Colonoscopy
Pelvic, prostate, and skin examinations
Upper endoscopy
Urine cytology
Liver function tests
Mammogram
Pap smear
Chest X-ray

What Cancers Are Linked to Muir-Torre Syndrome?

This genetic disease can cause multiple types of cancer that affect the whole body. Check the most common of them below:

Colorectal cancer – This is one of the most common types of cancer that is often associated with MTS. Approximately 50% of people with MTS develop it. It often appears in the lining of the colon or rectum. People with this type of cancer often experience the following symptoms. These include rectal bleeding, poop changes, bloating, and stomach pain.
Stomach cancer – This is another common cancer that occurs in people with MTS. While some symptoms are similar to colorectal cancer (including blood in the stool and stomach pain), it may also cause other symptoms, such as appetite changes, nausea, and indigestion.
Urinary cancer – In such cases, the tumor develops in the urothelium (a tissue that lines the urinary system).
Endometrial cancer – This type of cancer affects the endometrium, and it usually causes the following symptoms. For example, lower abdominal pain or pelvic pain, vaginal discharge, or bleeding.

However, there are other types of cancer that may also occur in people with MTS. These include:

Penile cancer
Liver cancer
Small intestine cancer
Testicular cancer
Ovarian cancer
Adrenal cancer
Lung cancer
Breast cancer
Bone cartilage cancer
Salivary gland cancer
Laryngeal cancer and others

For more details, discuss it with your doctor.

Treatment

The treatment is often different for people with MTS because it involves finding and treating cancer when it happens. That’s why doctors will perform regular cancer screenings and biopsies of any suspicious tissues. While the primary treatment is surgery to remove the tumor, doctors may also recommend a combination of the following options. These include:

Radiation therapy
Hormone therapy
Bone marrow transplant
Targeted therapy
Immunotherapy
Chemotherapy

Furthermore, your doctor may also prescribe an oral retinoid medicine (such as Isotretinoin) to prevent the development of new skin tumors.

Frequently Asked Questions

Is Muir-Torre syndrome the same as Lynch syndrome?

Generally, MTS is most of the time a variant of Lynch syndrome. It is a group of genetic disorders that significantly increases the risk of developing cancer. Sometimes, it is called by doctors hereditary non-polyposis colorectal cancer (HNPCC).

What is the survival rate for Muir-Torre syndrome?

Usually, the 5-year survival rate for people with MTS who get treatment is about 50%.

At what age does Muir-Torre syndrome typically appear?

Most diagnosed cases are in people around 50 years old. However, it still may occur at any age. If you have additional questions, ask your healthcare provider.