Papillary Thyroid Cancer (PTC)

What is papillary thyroid cancer (PTC)?

Papillary thyroid cancer begins in the follicular cells in your thyroid that produce thyroglobulin (a protein). It’s the most common type of thyroid cancer.

Your thyroid is a small, butterfly-shaped gland located at the front of your neck under your skin. It’s a part of your endocrine system and controls many of your body’s important functions by producing and releasing (secreting) certain hormones.

PTC tends to grow very slowly and usually develops in only one lobe of your thyroid gland.

There are several subtypes of papillary thyroid cancers. Of these, the follicular subtype (also called mixed papillary-follicular variant) is the most common. Other subtypes of papillary cancer aren’t as common and tend to grow and spread more quickly. They include:

• Columnar.
• Tall cell.
• Insular.
• Diffuse sclerosis.

Papillary thyroid cancer is also called papillary thyroid carcinoma.

Who does papillary thyroid cancer affect?

Papillary thyroid cancer can affect anyone, but it most commonly occurs in middle-aged adults. Women and people assigned female at birth (AFAB) are more likely to develop PTC than men and people assigned male at birth (AMAB).

Although PTC is rare in children, it’s still the most common pediatric thyroid cancer.

How common is papillary thyroid cancer?

Thyroid cancer is fairly common, and papillary thyroid cancer is the most common type. It accounts for 80% to 85% of all thyroid cancer cases.

Is papillary thyroid cancer serious?

While all cancer types are serious in that they require medical treatment and have the potential to spread to other parts of your body (metastasize), papillary thyroid cancer has the best overall prognosis of all thyroid cancer types.

PTC can often be treated successfully and is rarely fatal.

Where does papillary thyroid cancer spread first?

Papillary thyroid cancer is most likely to spread (metastasize) to the lymph nodes in your neck first. Lymph nodes are small bean-shaped structures that are part of your body’s lymphatic system and immune system.

How often does papillary thyroid cancer spread?

Even though papillary thyroid cancer grows slowly, PTC often spreads to the lymph nodes in your neck.

About 30% of people have metastatic papillary thyroid cancer (that has spread to other parts of their body) at diagnosis.

What are the symptoms of papillary thyroid cancer?

The main sign of papillary thyroid cancer is a painless lump or nodule on your thyroid gland. PTC usually doesn’t cause any other symptoms.

In rare cases, you may experience pain in your neck, jaw or ear from PTC. If the nodule is large enough to compress your windpipe or esophagus, it may cause difficulty with breathing or swallowing.

What causes papillary thyroid cancer?

Scientists still don’t know the exact cause of papillary thyroid cancer, but they have identified risk factors that increase your risk of developing PTC, including radiation exposure and certain genetic conditions.

Radiation exposure and papillary thyroid cancer

The rates of papillary thyroid cancer are higher in people who have a history of exposure to significant ionizing radiation. This exposure could be due to:

• High-dose external radiation treatments to your neck, especially during childhood, used to treat cancer or some noncancerous conditions.
• Radiation exposure from nuclear plant disasters. The Chernobyl nuclear accident in 1986 led to a 3- to 75-fold increase in PTC cases in fallout regions.

Genetics and papillary thyroid cancer

A few genetic (inherited) conditions are associated with PTC, including:

• Familial adenomatous polyposis (Gardner syndrome): Familial adenomatous polyposis (FAP) is a rare hereditary condition in which a person develops several precancerous polyps in their large intestine (colon and rectum). People with FAP are also at an increased risk of developing tumors in other areas of their body, including their thyroid. Gardner syndrome and FAP are due to an inherited mutation in the APC gene.
• Werner syndrome: Werner syndrome is a rare condition that’s characterized by the appearance of unusually accelerated aging (progeria). People with Werner syndrome have an increased predisposition to cancers. The most common cancers in Werner syndrome are thyroid cancers. More than 80 different mutations of the WRN gene have been identified in people with this condition.
• Carney complex type 1: Carney complex is a condition characterized by an increased risk of several types of tumors, including thyroid tumors. Mutations in the PRKAR1A gene cause most cases of Carney complex.

Only 5% of all papillary thyroid cases are associated with these genetic conditions.

How is papillary thyroid cancer diagnosed?

Papillary thyroid cancer usually presents as a lump or nodule on your thyroid gland. You may notice it, or your healthcare provider may discover it during a routine neck examination. Sometimes, the nodule is discovered incidentally (accidentally) by imaging tests you get for other medical reasons.

Your healthcare provider will likely order the following tests to help diagnose PTC:

• Imaging tests: Your provider may order imaging tests to identify the nodule on your thyroid. These tests might include thyroid ultrasound, CT (computed tomography) scan and/or magnetic resonance imaging (MRI).
• Fine needle aspiration (needle biopsy): Your provider will likely want to take a small tissue sample, called a biopsy, from the nodule on your thyroid using a very thin needle. A pathologist will look at the tissue under a microscope to see if there are cancer cells and, if so, what type of thyroid cancer it is.

Your healthcare provider may also recommend genetic counseling to see if you have a genetic condition that may have caused PTC and may cause other types of tumors.

How is papillary thyroid cancer treated?

Treatments for papillary thyroid cancer depend on the tumor size and whether the cancer has spread (metastasized).

Surgery is the most common treatment for PTC. Depending on the tumor’s size and location, your surgeon may remove part of your thyroid gland (lobectomy) or all of your gland (thyroidectomy). If you have cancer present in the lymph nodes of your neck, your surgeon may remove the affected lymph nodes at the time of the initial thyroid surgery or as a second procedure.

If you have a total thyroidectomy, you’ll need to take thyroid hormone replacement medication for the rest of your life.

Additional treatments for PTC include:

• Radioiodine (radioactive iodine) therapy: Thyroid cells and papillary thyroid cancer cells absorb iodine, a mineral found in some food. Because of this, healthcare providers sometimes use a radioactive form of iodine to destroy all remaining normal thyroid tissue and potentially destroy residual cancerous thyroid tissue after a thyroidectomy.
• Radiation therapy: Radiation kills cancer cells and stops them from growing. External radiation therapy uses a machine to deliver strong beams of energy directly to the tumor site. Internal radiation therapy (brachytherapy) involves placing radioactive seeds in or around the tumor.
• Chemotherapy: Intravenous (IV) or oral chemotherapy drugs kill cancer cells and stop cancer growth. Very few people diagnosed with thyroid cancer will ever need chemotherapy.

What are the possible side effects and complications of papillary thyroid cancer treatment?

Permanent hypothyroidism (low thyroid hormone levels) is an expected side effect of thyroidectomy and radioiodine therapy. Because of this, you’ll need to take replacement thyroid hormone medication for the rest of your life if you undergo either or both of these treatments.

Possible complications of thyroid surgery include:

• Infection.
• Accidental removal of or damage to your parathyroid glands, which help regulate your blood calcium levels.
• Damage to your recurrent laryngeal nerve, which runs behind your thyroid gland, resulting in hoarseness and a weak voice.

Potential side effects of radioactive iodine therapy include:

• Nausea and vomiting.
• Sialadenitis (swollen salivary gland).
• Transient thyrotoxicosis (excess thyroid hormone in your body).
• Pulmonary fibrosis (a lung disease that happens when lung tissue becomes damaged and scarred).
• Infertility.
• Small risk of leukemia, breast or bladder cancer.

Can papillary thyroid cancer be prevented?

Most people with thyroid cancer have no known risk factors, so it’s not possible to prevent most cases of papillary thyroid cancer.

Radiation exposure, especially in childhood, is a known PTC risk factor. Because of this, healthcare providers no longer use radiation to treat less serious diseases. Imaging tests, such as X-rays and CT scans, also expose children to radiation, but at much lower doses. It’s not clear how much they might increase the risk of PTC.

If you have a family history of thyroid cancer, you may want to get genetic counseling to see if you have any inherited conditions that put you at a higher risk of developing PTC. If this is the case, your healthcare provider may recommend getting preventive (prophylactic) surgery to remove your thyroid gland before cancer develops.

What is the prognosis (outlook) of papillary thyroid cancer?

Overall, the prognosis of papillary thyroid cancer is excellent, especially if you’re younger than 40 at diagnosis and have a small tumor. PTC can often be treated successfully and is rarely fatal, even if it has spread to lymph nodes in your neck.

Factors that may lead to a worse prognosis include:

• Being older than 55 years at diagnosis.
• Having a large tumor.
• If the cancer has spread to distant parts of your body.
• If you have a rare subtype of PTC, which are typically more aggressive, including the tall cell variant, diffuse sclerosis variant or solid variant.

Can you survive papillary thyroid cancer?

The survival rate for papillary thyroid cancer is excellent. More than 90% of adults with PTC survive at least 10 to 20 years after treatment.

When should I see my healthcare provider about papillary thyroid cancer?

If you’ve been diagnosed with papillary thyroid cancer, you’ll need to see your healthcare team regularly to monitor your treatment progress. You’ll also need long-term monitoring every six to 12 months to look for cancer recurrence (when it comes back) for at least five years.

If you had your thyroid removed and/or had radioactive iodine therapy as part of treatment, you’ll need to take thyroid hormone medication for the rest of your life. Your healthcare provider will want to monitor your thyroid hormone levels throughout your life to make sure your medication dosage is working for you.

A note from Cleveland Clinic

Receiving a cancer diagnosis is unsettling, regardless of the type. The good news is that papillary thyroid cancer (PTC) often has an excellent prognosis. Your healthcare team will work with you to determine the best treatment plan for you.