Follicular thyroid cancer symptoms & treatment

Follicular thyroid cancer, or follicular thyroid carcinoma, is one of two primary types of thyroid cancer, the other being papillary thyroid cancer.

Both involve the growth of cancerous cells within the thyroid gland, situated at the base of your neck. However, there are notable differences between follicular thyroid cancer and papillary thyroid cancer. These differences include the specific cells targeted by the cancer, their appearance when examined under a microscope and the likelihood of these cells spreading to other parts of the body.

What is follicular thyroid cancer?

Follicular thyroid cancer arises from the outer layer of cells in the thyroid gland, which are responsible for producing and releasing thyroid hormones, namely T3 and T4.

While produced in tiny amounts, T3 thyroid hormones are important to regulating metabolism and cellular function. Conversely, T4 is released in larger quantities and helps with your heart rate and body temperature.

A characteristic of follicular carcinoma is the formation of small follicles or hollow round structures within the thyroid tissue. These cancer cells can invade nearby tissues and spread to distant sites, notably the lymph nodes, lungs and bones.

What are the differences between papillary and follicular thyroid cancer?

Papillary thyroid cancer is more widespread, constituting 80% of all thyroid cancer cases, whereas follicular thyroid cancer comprises about 15% of all diagnoses.

While both cancers originate in thyroid cells, their microscopic appearance differs significantly. Papillary thyroid cancer cells resemble tiny finger-like projections, whereas follicular thyroid cancer cells look like follicles or solid structures.

And there’s a difference in who gets each type. Papillary thyroid cancer tends to emerge at a younger age and disproportionately affects women. On the other hand, follicular thyroid cancer typically occurs in older individuals and impacts men and women the same.

Follicular thyroid cancer symptoms

You might not have any symptoms, especially in the early stages. However, as the cancer advances, you may experience symptoms such as:

• A painless lump on the front of your neck, or a thyroid nodule
• An enlarged thyroid gland
• Breathing difficulties
• Hoarseness or voice changes
• Pain in the neck
• Swollen lymph nodes

Many of these symptoms may be caused by noncancerous conditions affecting the thyroid gland, such as inflammation. Schedule an appointment with your provider if you notice any of these symptoms. Early detection is crucial to increasing the success of treatments.

Diagnosing follicular thyroid cancer

Your doctor will evaluate your medical history, inquire about any family history of thyroid cancer and perform a physical exam of your thyroid gland. During the exam, they’ll check for the presence of a goiter, which is a noticeable enlargement of the thyroid gland, or a lump.

If your doctor suspects follicular thyroid cancer, they may recommend additional tests, which can include:

• Digital imaging tests: Your doctor may recommend an MRI or CT scan to obtain detailed images of the thyroid gland.
• Biopsy: This procedure involves the removal of a small piece of thyroid tissue for microscopic evaluation to determine if cancerous cells are present.
• Fine needle aspiration biopsy: A thin needle is inserted into the lump on your neck to extract cells to identify cancerous cells under the microscope.
• Core needle biopsy: If the fine needle aspiration biopsy results are inconclusive, your doctor may opt for a core needle biopsy, which involves using a larger needle.

Once follicular thyroid cancer is diagnosed, additional tests may be conducted to determine the stage of the cancer and plan appropriate treatment. These tests may include blood tests, further imaging studies and sometimes surgery to remove the thyroid gland for both diagnosing follicular thyroid cancer and treating it.

Follicular thyroid cancer treatment 

Your treatment approach for follicular thyroid cancer depends on several factors, including the cancer's stage, your overall health and preference of treatment.

Typically, the primary treatment for most types of thyroid cancer, including follicular cancer, involves a thyroidectomy. A partial thyroidectomy removes part of the thyroid gland, whereas a full thyroidectomy is the removal of the entire thyroid gland.

Your surgeon may also remove affected lymph nodes during your thyroidectomy if the cancer has spread to them, depending on the size and location of the tumor.

Following surgery, radioactive iodine ablation is often performed to eradicate any residual thyroid tissue. This procedure entails injecting radioactive iodine into the thyroid tissue. Since the thyroid absorbs iodine, the radiation effectively destroys the remaining tissue.

If you undergo partial or total thyroid removal, you’ll need thyroid hormone replacement therapy. Your doctor will prescribe thyroid hormone pills to supply your body with the necessary thyroid hormones. These pills not only fulfill your body's thyroid hormone needs but also help prevent the growth and recurrence of any remaining cancer cells by reducing the level of thyroid-stimulating hormone.

In cases of more advanced follicular thyroid cancer, treatment may involve nonsurgical options such as chemotherapy or radiation therapy to target and combat the cancer cells.

How treatable is follicular thyroid cancer?

Follicular thyroid cancer is typically highly treatable, especially when diagnosed early. The success of treatment depends on a range of factors, including the cancer's stage upon diagnosis, whether it has spread, your age, your overall health and the characteristics of the cancer cells.

Compared to more aggressive thyroid cancers such as anaplastic thyroid cancer, follicular thyroid cancer tends to progress more slowly. Consequently, early detection significantly improves your chances of successful treatment.

It's important to disscuss treatment options with your multidisciplinary care team at Aurora Health Care. Your care team may consist of endocrinologists, surgeons, oncologists and radiation oncologists. By working together, they can craft a personalized treatment plan tailored to your needs to maximize the effectiveness of your treatment.