Quick answer. Thyroid cancer usually appears as a painless lump or nodule in the front of the neck. Most types are very treatable, and the main treatments are surgery and, where needed, radioactive iodine.
Thyroid cancer is a growth that starts in the thyroid, the small butterfly-shaped gland at the front of the neck that helps control metabolism. It most often shows up as a painless lump or nodule in the neck. While the word cancer is always worrying, the most common types of thyroid cancer are among the most treatable, and many people do very well after treatment.
Most thyroid nodules are not cancerous, but any new or growing neck lump should be checked. This guide explains the signs of thyroid cancer, the risk factors, how it is diagnosed using ultrasound and a fine-needle biopsy, and the main treatment options. It focuses on cancer specifically, as distinct from the broader topic of thyroid nodules and goitre.
At a glance
| Step | What is involved | Purpose |
|---|---|---|
| Neck lump found | Examination by a doctor | Decide if further tests are needed |
| Ultrasound | Scan of the thyroid and neck | Look at the nodule and nearby lymph nodes |
| Fine-needle biopsy (FNA) | Thin needle samples the nodule | Check whether cells are cancerous |
| Surgery | Remove part or all of the thyroid | Main treatment for most thyroid cancers |
| Radioactive iodine | Swallowed treatment after surgery | Target any remaining thyroid tissue or cells |
What is thyroid cancer?
Thyroid cancer develops when cells in the thyroid gland grow in an abnormal, uncontrolled way and form a lump. The thyroid sits at the front of the lower neck and produces hormones that regulate metabolism. There are several types of thyroid cancer; the most common ones (papillary and follicular) are usually slow-growing and highly treatable.
It can affect adults of any age and is seen more often in women. Importantly, the great majority of thyroid lumps and nodules are not cancer – but because a small proportion are, a new or changing neck lump is worth getting assessed. When thyroid cancer is found, the outlook for the common types is generally very good.
Symptoms and signs
Thyroid cancer often causes few symptoms early on, and may be found as a painless lump. Signs to be aware of include:
- A painless lump or swelling in the front of the neck
- A lump that is growing or feels firm
- A hoarse voice that does not settle
- Difficulty swallowing or a feeling of something stuck in the throat
- Difficulty breathing in some cases
- Swollen lymph nodes in the neck
Many of these can be caused by harmless conditions, but a rapidly growing neck lump, a persistently hoarse voice or trouble swallowing should always be checked by a doctor.
Causes and risk factors
The exact cause is usually not known, but some factors are linked to a higher risk:
- Exposure to radiation, particularly to the head and neck in childhood
- A family history of thyroid cancer or certain inherited conditions
- Being female
- Certain pre-existing thyroid conditions
- Some dietary iodine factors in particular populations
Most people who develop thyroid cancer have no clear risk factor, so it is not something that can usually be predicted or prevented. The focus is on getting any suspicious neck lump assessed promptly.
How it is diagnosed
If a thyroid lump or other sign is found, the doctor will usually arrange a step-by-step assessment:
- Examination of the neck and lymph nodes
- Blood tests to check thyroid hormone levels
- Ultrasound of the thyroid and neck to look closely at the nodule and any nearby lymph nodes
- Fine-needle aspiration (FNA) biopsy – a thin needle takes a small sample of cells from the nodule to check whether it is cancerous; this is the key test
- Further scans if needed to assess whether the cancer has spread
This stepwise approach means most harmless nodules can be reassured, while the small number that are cancer are identified and treated.
Treatment options
Treatment depends on the type and extent of the cancer, but most thyroid cancers respond well. The main options are:
- Surgery – removing part of the thyroid (lobectomy) or the whole gland (total thyroidectomy), sometimes with neck lymph nodes; this is the main treatment for most cases
- Radioactive iodine therapy – a treatment swallowed after surgery that targets any remaining thyroid tissue or cancer cells
- Thyroid hormone tablets – taken to replace the gland’s function after surgery and, in some cases, to help suppress regrowth
- Other treatments such as targeted therapy or radiotherapy for less common or advanced types
Costs vary widely with the type of surgery, hospital and ward class, so a personalised estimate from your treating team is best. Treatment in public hospitals may be subsidised, and approved cancer treatments and hospital stays can draw on MediShield Life and, within limits, MediSave – confirm current details with the hospital and your insurer, as financing rules are reviewed periodically.
When to see a doctor and which specialist
See a doctor if you notice a lump in the front of your neck, especially one that is growing, or if you have a hoarse voice or difficulty swallowing that does not settle. Most lumps are not cancer, but it is important to have them checked.
See a doctor promptly for a rapidly growing neck lump, a persistently hoarse voice, or increasing difficulty swallowing. Seek urgent care or go to A&E if a neck swelling is causing breathing difficulty – and call 995 if breathing becomes severely obstructed or you are struggling to breathe.
Thyroid conditions are assessed by an endocrinologist (a hormone specialist), with a cancer specialist involved for treatments such as radioactive iodine. You can find a specialist through the Best Doctors Singapore directory of endocrinologists in Singapore or oncologists in Singapore.
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Sources
- NHS – Thyroid cancer
- Mayo Clinic – Thyroid cancer
- HealthHub Singapore – Cancer
- SingHealth – Endocrinology conditions and treatments
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