How Theranostics is Transforming Thyroid Cancer Treatment
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How Theranostics is Transforming Thyroid Cancer Treatment
Thyroid cancer develops when abnormal cells grow uncontrollably within the thyroid – a small, butterfly-shaped gland located at the base of the neck. The thyroid produces hormones that help regulate many important functions in the body, including metabolism, heart rate and body temperature.
There are several types of thyroid cancer, and treatment will depend on factors such as the type of cancer, its stage, whether it has spread and the individual needs of the patient.
What are the Symptoms of Thyroid Cancer?
Thyroid cancer may not cause noticeable symptoms in its early stages. As the cancer develops, signs and symptoms may include:
A painless lump or swelling in the neck
Persistent changes to the voice, including hoarseness
Difficulty swallowing or breathing
Swollen lymph nodes in the neck
Ongoing pain in the neck or throat
Many of these symptoms can also be caused by non-cancerous conditions. However, any new, persistent or unexplained changes should be discussed with a healthcare professional.
What Treatment Options are Available?
Treatment for thyroid cancer is personalised according to the type and extent of the disease. Options may include:
Surgery
Surgery is the most common treatment and may involve removing part or all of the thyroid gland. Nearby lymph nodes may also be removed if the cancer has spread.
Thyroid hormone therapy
Following thyroid surgery, patients may need to take thyroid hormone replacement medication. In some cases, this treatment can also help reduce stimulation of any remaining thyroid cancer cells.
Radioactive iodine therapy
Radioactive iodine, also known as radioiodine or I-131 therapy, may be used after surgery for certain differentiated thyroid cancers. It can help destroy remaining thyroid tissue or cancer cells and may also be used when iodine-avid cancer has spread to other parts of the body.
External beam radiation therapy
External radiation may be considered in selected cases, particularly when the cancer cannot be completely removed through surgery or has spread to nearby tissues.
Targeted therapies and other medicines
For some advanced thyroid cancers, targeted therapies or other systemic treatments may be considered. Chemotherapy has a limited role but may be used in selected circumstances.
Theranostics and Thyroid Cancer
The word theranostics combines two concepts: therapy and diagnostics. It uses a biological target to help identify disease and guide targeted treatment.
Radioactive iodine is one of the earliest and most established examples of this approach.
Thyroid cells naturally absorb iodine to produce thyroid hormones. Many differentiated thyroid cancer cells retain this ability, creating an opportunity to use radioactive forms of iodine for both imaging and treatment.
Diagnostic imaging can help identify whether thyroid tissue or cancer cells are taking up iodine and where they are located within the body. When appropriate, radioactive iodine therapy can then use the same biological pathway to deliver radiation directly to iodine-absorbing cells.
This targeted approach can help limit radiation exposure to many surrounding tissues.
How is Radioactive Iodine Treatment Administered?
Radioactive iodine is generally taken orally as a capsule or liquid. Once swallowed, it enters the bloodstream and is absorbed by thyroid cells and iodine-avid thyroid cancer cells.
I-131 emits beta radiation, which delivers treatment to nearby cells, as well as gamma radiation, which can be detected using specialised imaging equipment. Imaging after treatment may help clinicians understand where the radioactive iodine has accumulated.
Treatment may require a short period in a specially designed hospital room while radiation levels decrease. Once levels meet approved safety requirements, patients can return home with personalised instructions about limiting close contact with others for a period of time.
Before treatment, patients may undergo blood tests, imaging and preparation to increase thyroid-stimulating hormone levels. Follow-up may include blood tests, imaging and ongoing monitoring to assess treatment response.
Is Radioactive Iodine Suitable for Everyone?
Radioactive iodine is not required for every person with thyroid cancer. It is most commonly used for selected papillary, follicular and oncocytic thyroid cancers because these cancer cells may retain the ability to absorb iodine.
Some thyroid cancers, including medullary and anaplastic thyroid cancers, generally do not take up iodine and are treated using different approaches.
Eligibility depends on the cancer type, stage, risk of recurrence, previous treatment and individual clinical circumstances. A multidisciplinary healthcare team can determine whether radioactive iodine or another treatment approach is appropriate.
A Longstanding Example of Targeted Cancer Care
Radioactive iodine has been used in thyroid cancer care for decades and remains one of the clearest examples of the principles behind theranostics: using the unique biology of cancer to help detect, target and treat disease.
As molecular imaging and targeted radiopharmaceutical therapies continue to advance, this personalised approach is helping shape the future of precision cancer care.
