Thyroid cancer treatment is changing; why your treatment plan may be different from someone else’s

Being diagnosed with thyroid cancer does not necessarily mean that every patient will follow the same treatment path.

One person may need surgery followed by radioactive iodine. Another may need surgery but no further treatment. Some carefully selected patients with low-risk disease may be monitored rather than treated immediately. For certain patients with advanced disease, information about the tumour’s molecular characteristics may help doctors identify additional treatment options.

This increasingly individual approach to thyroid cancer care is one of the most important developments of the past decade.

The American Thyroid Association (ATA) updated its guidelines for differentiated thyroid cancer in 2025, ten years after publishing the previous guidelines. During that time, thyroid tumour classification has changed significantly, as have how doctors assess recurrence risk and how molecular information informs treatment decisions.

Understanding these changes can help patients understand why their own treatment plan may look different from that of another person with thyroid cancer.

Not all thyroid cancers behave in the same way

The term “thyroid cancer” covers tumours that can behave very differently.

Doctors have traditionally relied heavily on what a tumour looks like under the microscope. This remains fundamental, but we now have additional information that can help us understand a tumour’s likely behaviour.

The latest World Health Organisation classification incorporates molecular and genetic information alongside the tumour’s pathological features and biological behaviour. It also more clearly distinguishes between benign, low-risk, and malignant thyroid neoplasms.

NIFTP (non-invasive follicular thyroid neoplasm with papillary-like nuclear features) is one example.

Although previously viewed through a cancer lens, NIFTP is now classified as a low-risk neoplasm rather than a malignant thyroid tumour. This matters because understanding risk helps doctors avoid treating a low-risk condition as though it were an aggressive cancer.

For patients, it reinforces an important point: the name of the diagnosis is only one part of the information used to determine what happens next.

Your risk after treatment is not necessarily fixed

When cancer is diagnosed, staging helps doctors understand the extent of the disease and its prognosis.

With differentiated thyroid cancer, however, doctors can also reassess a patient’s risk according to how well they respond to treatment.

This is called dynamic risk stratification.

For example, someone who initially requires treatment but later responds well may eventually need less intensive follow-up. A patient who continues to show evidence of disease will require a different approach.

This means your follow-up plan may change over time because your medical team has more information about how your individual cancer is behaving.

For a cancer in which many patients require long-term follow-up, this is an important development.

When is molecular testing useful?

One of the areas of greatest development in thyroid cancer is our understanding of its molecular biology.

Cancer develops because of changes within cells. Different thyroid tumours can have different molecular alterations, and testing for these changes can sometimes give doctors useful additional information.

Molecular testing may help clarify a diagnosis or provide information about how a tumour is likely to behave. In selected cases, it can inform decisions about surgery, treatment after surgery, and follow-up.

However, not every patient with thyroid cancer needs molecular testing.

Whether it will be useful depends on the individual tumour and, importantly, whether the result is likely to change the patient’s management.

Molecular information becomes particularly relevant in some cases of advanced thyroid cancer.

What happens if radioactive iodine stops working?

Radioactive iodine can be an important treatment for differentiated thyroid cancer when it is indicated. However, some advanced cancers eventually stop responding. Doctors refer to this as radioactive iodine-refractory disease.

Systemic treatments are available for these patients.

In selected cases, molecular testing can also identify specific changes within the cancer, including alterations involving RET, NTRK or BRAF. Some of these can be targeted with treatments designed to act on the particular molecular change driving the tumour.

This is an example of personalised, or precision, medicine: using information about an individual cancer to identify a treatment that may be particularly relevant.

It is not appropriate or necessary for every thyroid cancer patient, but for selected patients with advanced disease it has created treatment possibilities that were not previously available.

Why might a doctor recommend monitoring rather than immediate treatment?

Perhaps one of the more surprising changes in thyroid cancer management is that immediate intervention is not always the best option.

For carefully selected patients with low-risk disease, doctors may consider active surveillance. Active surveillance does not mean ignoring the cancer.

It is a structured medical approach in which clinicians carefully select and monitor the patient. If evidence shows the disease is changing, treatment can then be considered.

This is why it is important to understand the reasoning behind a recommendation for active surveillance. Patients should know what will be monitored, how frequently follow-up will take place and what findings would prompt their medical team to reconsider the approach.

Why your treatment may be different from someone else’s

It can be confusing when two people with thyroid cancer compare their experiences and discover that their doctors have recommended very different things.

That does not necessarily mean one person is being undertreated or the other is receiving too much treatment.

Their cancers may differ in important ways.

Doctors consider the type and characteristics of the tumour, the extent of disease, the patient’s risk of recurrence and, after treatment, how well the patient has responded. In some circumstances, molecular information may provide another piece of the picture.

This is also why treatment decisions need to be made for the individual patient, rather than based on what happened to a friend, family member, or someone sharing their experience online.

If you have been diagnosed with thyroid cancer, it is important to understand why a particular approach is being recommended for you. Ask your treating team to talk you through your diagnosis, your individual risk and what they expect from treatment. Depending on your circumstances, that conversation may also include whether radioactive iodine or molecular testing is relevant, whether active surveillance is an option, and what your follow-up is likely to involve.

It is also helpful to know what could change the plan. Thyroid cancer management increasingly depends on what doctors learn about the tumour and how a patient responds over time, so the approach recommended at diagnosis is not necessarily fixed indefinitely.

Thyroid cancer care has changed considerably over the past decade. We have more information about the disease, more ways to assess risk, and, for some patients, treatment options that were not previously available.

The important part is using those advances where they can make a meaningful difference to the individual patient.