Cowden Syndrome

Cowden syndrome is a rare inherited condition. People who have it often have many benign (noncancerous) tumor-like growths. They may also develop different kinds of early-onset cancer that may develop between the ages of 30 and 50, including:

• Breast cancer
• Endometrial (uterine) cancer
• Colorectal cancer
• Kidney cancer
• Melanoma
• Thyroid cancer, specifically follicular thyroid cancer

Experts estimate this condition may affect as many as 1 in 7,5000 people. Cowden syndrome is part of the larger syndrome PTEN hamartoma tumor syndrome (PHTS). Some experts use the terms interchangeably.

Symptoms of Cowden syndrome

The first symptom may be wart-like growths (trichilemmomas) on your face and neck. You may have rough spots on your hands. Other common symptoms are:

• A large head
• Belly pain or rectal bleeding from a noncancerous tumor (hamartoma)
• Wart-like bumps on your tongue, gums, the back of your throat and your tonsils (oral papillomatosis)

Cowden syndrome causes

A change in the PTEN gene is the most common cause. This gene normally keeps cells from multiplying. With Cowden syndrome, the changed gene gives cells instructions to grow uncontrollably. The cells can eventually form noncancerous and cancerous growths.

People may inherit the genetic change from one of their biological parents. If one of your parents has a change in the PTEN gene, there’s a 50% chance that you’ll inherit that change.

But some people have the changed gene without inheriting it from their parents. And research shows other changed genes, including PIK3CA/AKT1, SDHB-D, KLLN and SEC23B, may also cause syndrome symptoms.

The only known risk factor is inheriting the genetic change that causes the syndrome. Your provider may suspect you have this if several family members have early-onset cancer.

How do doctors diagnose Cowden syndrome?

People with this disease typically develop certain conditions. A healthcare provider may suspect you may have Cowden syndrome if you have several of these.

There are two sets of conditions that providers may refer to as major and minor criteria. The term “criteria” refers to conditions that are common in people with the syndrome:

• Two or more conditions from the major criteria list that typically affect people with the syndrome
• One condition from the major criteria list and three from the minor criteria list
• One condition from the major list
• Four or more conditions from the minor list

Conditions on the major criteria list include:

• Breast cancer
• Endometrial cancer
• Epithelial thyroid cancer, especially follicular thyroid cancer
• Large head (macrocephaly)

Conditions on the minor criteria list include:

• Adenoma, multimodal goiter and other thyroid issues
• Fibrocystic disease of the breast
• Fibromas
• Genitourinary tumors, especially renal cell carcinoma
• Hamartomatous polyps
• Intellectual disability
• Issues with the structure of your urinary or reproductive systems
• Lipomas
• Uterine fibroids

Your provider will do genetic testing if they think you have Cowden syndrome.

How is Cowden syndrome treated?

Healthcare providers treat the specific conditions the syndrome causes. They’ll recommend cancer screening if you have the syndrome but don’t have cancer signs or symptoms. Your screening schedule may depend on your family medical history.

General health screening

Your healthcare provider will ask about your health, specifically if you’ve had any conditions that are linked to Cowden syndrome. They’ll ask if any family members have had or have those conditions.

They’ll do a comprehensive annual physical exam that includes checking your thyroid. They may schedule exams to start when you turn 18.

Your provider may recommend that you have annual exams before you turn 18 if a biological family member has certain kinds of cancer. For example, if your sibling was 20 when they had breast cancer, your provider may begin annual exams when you turn 15.

They may discuss your risk of cancer and recommend resources so you can learn more about the condition.

Breast cancer screening

Your screening schedule may look like this:

• Age 18: Your provider will explain the importance of breast self-exams. Knowing what your breasts look and feel like helps make it more likely you’ll notice changes. Don’t hesitate to tell your provider about changes.
• Age 25: Your provider will do a breast exam every six to 12 months.
• Ages 30 to 35: You’ll have annual digital breast tomosynthesis (3D mammography) and breast MRI with contrast. You and your provider may talk about preventive mastectomy. 

Thyroid

You may have annual thyroid ultrasounds starting at age 7.

Kidney cancer screening

You’ll have regular imaging tests to check for kidney cancer. Your provider may recommend that you have a kidney ultrasound every year. You may also have regular CT or MRI scans.

Endometrial cancer screening

Your provider will discuss what symptoms that you should watch for, like unusual bleeding. They may recommend you have the following tests:

• After age 35: Annual endometrial cancer screening and endometrial biopsy every year to every two years.
• After menopause: Your provider may recommend that you have a transvaginal ultrasound.

You and your provider may also discuss a hysterectomy as preventive surgery or as needed to treat endometrial cancer.

Colon cancer screening

You’ll have regular colonoscopies every five years, starting at age 35. You may have more frequent checks if a colonoscopy detects a polyp or if you have colorectal cancer symptoms.

Skin

Cowden syndrome increases your risk of melanoma and other skin cancers. Your provider may recommend an annual skin exam, starting when you turn 20.

Developmental issues

People with Cowden syndrome may have developmental delays. If that’s your child’s situation, their healthcare provider may recommend tests, including;

• Brain MRI and psychomotor assessment
• Evaluation for early intervention services

What can I expect if I have Cowden syndrome?

That depends on your situation. If you have cancer, your healthcare provider is your best source of information about what you can expect. If you have the syndrome, your provider will schedule regular check-ups and cancer screening tests.

You can pass on the changed gene to your biological children. If you’re planning to have a family, you may want to work with a genetic counselor. They’ll help you understand the risk of your children inheriting the syndrome.