Understanding Metastatic Papillary Thyroid Cancer

Understanding Metastatic Papillary Thyroid Cancer

When papillary thyroid cancer spreads to other remote areas of your body, such as your bones or lungs, it is referred to as metastatic thyroid cancer.

Treatment for metastatic papillary thyroid carcinoma, commonly known as papillary thyroid cancer, is more challenging than for cancer that is restricted to the thyroid gland or surrounding tissue.

The majority of patients with early-stage papillary thyroid cancer respond well to surgery that involves the removal of all or part of the thyroid gland.

Individuals who have metastatic papillary cancer may require supplementary therapies, like targeted therapy or radiation therapy.

Continue reading to find out more about metastatic papillary thyroid cancer, including its prognosis and course of treatment.

What is metastatic papillary thyroid cancer?

The most prevalent kind of thyroid cancer is called papillary thyroid cancer. It accounts for 80–85% of cases. Its name originates from the appearance of projections that resemble fingers, known as papillae, which originate from cancer cells.

Most patients have the illness in the thyroid gland or surrounding tissue when they are diagnosed.

In the United States, just 2.1% of patients identified between 2011 and 2020 had metastatic illness at the time of diagnosis.

malignancies that spread through the blood or lymphatic systems to distant tissues from the primary organ are referred to as "metastatic" malignancies. Metastases are the new places affected by cancer.

The following are the most typical sites of metastases from papillary thyroid cancer:

• lungs

bones, such as the:

• sternum
• femur
• ribs
• pelvis
• vertebrae

Is metastatic papillary thyroid cancer curable?

Treatment for metastatic papillary thyroid cancer is more challenging than for papillary malignancies that have not metastasized. But compared to most other forms of metastatic cancer, it has a higher likelihood of recovery.

About 75% of those with metastatic papillary thyroid cancer survive for at least five years after receiving their diagnosis, compared to those without thyroid cancer.

What stage of cancer is metastatic papillary thyroid cancer?

Stage 4 or stage IV papillary thyroid carcinoma is another name for metastatic thyroid cancer.

The term "Stage 4" refers to the TNM system used by the American Joint Committee of Cancer (AJCC) to stage cancer, which is determined by three factors:

• T: the size of the tumor
• N: how many lymph nodes in the area it has spread to
• M: metastatic status, or if the cancer has moved to other organs

Papillary thyroid cancer by stage

The AJCC's TNM system provides a concise summary of the differences between papillary thyroid carcinoma stages:

• Stage 1: If the patient is under 55 years old, the malignancy is limited to the thyroid gland or the surrounding lymph nodes.
• Stage 2: In a person under 55, the cancer has migrated to distant tissues or surrounding lymph nodes.
• Stage 3: In an individual over 55, the cancer has progressed well beyond the thyroid gland and into adjacent lymph nodes, but it hasn't reached distant regions.
• Stage 4: Only those above 55 are permitted to participate in this level. At this point, the cancer has progressed to far-off tissues within or far beyond the thyroid gland, affecting the spine or important blood vessels.

 

How is metastatic papillary thyroid cancer treated?

Iodine is a necessary mineral that your thyroid gland needs to produce thyroid hormone. Whether iodine uptake by papillary thyroid cancer cells affects the malignancy's course of treatment.

The following therapies are used for iodine-absorbing metastatic papillary thyroid cancers:

• total thyroidectomy, or the thyroid gland removed entirely
• radiation treatment with radioactive iodine, in which the radiation kills cancer cells
• hormone treatment to stop the thyroid from producing hormone that stimulates the thyroid

For non-iodine-absorbing metastatic papillary thyroid tumours, the following treatments are available:

• total thyroidectomy
• surgery for metastases
• external-beam radiation therapy
• hormone therapy
• Using tyrosine kinase inhibitors for targeted therapy

Clinical studies for various therapies, such as:

• targeted therapy
• immunotherapy
• chemotherapy

What is the prognosis for a patient with papillary thyroid carcinoma that has spread?

Physicians frequently gauge a cancer patient's chance of survival using the 5-year relative survival rate. This statistic compares the number of cancer patients who survive five years after diagnosis to that of non-patients.

The 5-year relative survival rate for papillary thyroid carcinoma in the US from 2012 to 2018 is shown below:

Stage	5-year relative survival rate
localized (contained to the thyroid)	greater than 99.5%
regional (contained to nearby tissues)	99%
distant (metastatic)	74%
all stages	greater than 99.5%

Researchers discovered in a 2021 study that individuals in the US diagnosed with metastatic thyroid cancer between 1975 and 2016 had a worse chance of surviving if the illness had spread to more than one organ or the brain.

Thyroid cancer patients under 40 typically have better prognoses.

Takeaway

Treatment for metastatic papillary thyroid carcinoma is more challenging than for cancer that hasn't progressed to other distant areas of the body. Its prognosis is still better than that of many other cancer forms, though.

The standard course of treatment for metastatic papillary thyroid cancer is thyroid gland excision. Additional therapies like targeted therapy or radioactive thyroid therapy might be administered to you as well.

Seeking medical attention as soon as feasible could enhance your prognosis.