Thyroid Nodules, Cancer & RFA: 20 Questions Answered

Lightly edited for readability from the live webinar on 30 September 2026. Presented by Dr Ebrahim Yusuf.

Part 1 — The thyroid, nodules & goitre

Do I have a thyroid? People ask me this all the time — often meaning it as a disease. But everyone has a thyroid. It is a small, butterfly-shaped gland at the front of the neck, just below the Adam's apple. Its hormones travel throughout the body and affect almost every organ: mood, memory and concentration; heart rate and blood pressure; digestion, bowel habit and weight; fluid and salt balance; and menstruation and fertility. It is a small organ, but a very important one.

What is a thyroid nodule? A nodule is a lump, or an overgrowth of tissue, within the thyroid. There are several types: cystic nodules contain fluid; solid nodules are made of thyroid tissue; and mixed nodules contain both. You may have one nodule or several. The key thing to remember is that not all nodules are cancer.

How common are thyroid nodules? They are very common. Only a few can be felt or seen — about 5%. On ultrasound, some studies find nodules in up to half of people; so out of twenty people here, ten might have one. Most people diagnosed are women — roughly fifteen of those twenty. Ultrasound is the most sensitive way to find a nodule.

Why do thyroid nodules develop? Colloid nodules — which contain fluid — are the most common. You may also have a multinodular goitre, a nodule that turns out to be a cancer, or nodules from inflammation, as in Hashimoto's thyroiditis or Graves' disease.

What is a goitre, and how is it different from a nodule? People ask whether they have a goitre or a nodule — and often the answer is both. Goitre is simply an umbrella term meaning the thyroid is enlarged. It may be enlarged by a single nodule, by multiple nodules (a multinodular goitre), or diffusely with no distinct nodules, as in Hashimoto's thyroiditis or Graves' disease. With a nodule, the thyroid may work normally, or it may over-produce hormone — a toxic adenoma.

Do nodules or goitre cause symptoms? Often there are no symptoms at all. Many nodules are found by chance — on a scan done for another reason, or when a spouse notices the neck looks fuller. Symptoms tend to appear as a nodule enlarges: a visible swelling or cosmetic concern, a feeling of a lump or pressure, difficulty swallowing, a hoarse or changed voice from pressure on the nerves, or difficulty breathing if it presses on the windpipe.

Part 2 — Investigating a nodule

How do you diagnose a thyroid nodule? Usually the nodule has already been seen on a scan. From there it is important to go through a proper assessment. First a blood test, to see whether the thyroid is over- or under-producing hormone. Then a thyroid ultrasound, where we carry out a risk assessment — does this nodule look suspicious? That guides whether a biopsy is needed: a fine-needle aspiration, or a core-needle biopsy, which takes a little more tissue.

What does a thyroid ultrasound actually tell us? We look at the nodule's composition — solid, or containing fluid? Its brightness, or echogenicity — is it darker than normal thyroid? Its shape — taller or wider? Its margins — smooth or ragged? Any bright spots, which we call calcifications. The blood flow within it and the surrounding tissue. And we check the neck for any lymph nodes that might point to something more serious.

What makes a nodule look suspicious? A simple nodule has smooth, well-defined edges. Ragged or irregular edges raise suspicion a little. A nodule taller than it is wide raises it further. Bright spots begin to point towards something more suspicious, such as cancer. No single feature is decisive — it is the combination that matters.

Does every thyroid nodule need a biopsy? During the ultrasound we place each nodule into a scoring system — the ACR TI-RADS score, from the American College of Radiology. It runs from TR1 (benign) and TR2 (not suspicious), through TR3 (mildly suspicious, which may or may not need a biopsy), to TR4 and TR5, which usually do. For TR1 and TR2 we usually don't biopsy; we follow up with a repeat ultrasound, or consider a minimally invasive treatment.

How accurate is a thyroid biopsy? A biopsy does not stand alone — thyroid nodules need the ultrasound, the examination, the history and the biopsy together. A fine-needle aspiration (FNAC) collects cells to examine under the microscope; a core-needle biopsy takes a slightly larger piece of tissue. Results may be non-diagnostic (often when a cystic nodule yields only fluid), benign, intermediate, suspicious, or malignant. Both the ultrasound and the biopsy have limitations.

What are the chances a nodule is cancer? Roughly 5 out of 100 thyroid nodules are cancer. The risk varies with age, sex, family history, previous radiation to the neck — for example after treatment for head and neck tumours — and how the nodule looks on ultrasound. My job is not to assume every nodule is cancer, but to find the small minority that need closer attention.

Part 3 — Thyroid cancer

What is thyroid cancer? Thyroid cancer starts in thyroid cells, and it is not a single disease. Papillary thyroid cancer is the most common; it usually grows slowly, has an excellent outlook, and can often be cured. Follicular cancer is less common but also has good outcomes. Medullary thyroid cancer is rare, can run in families, and may occur with other tumours. The rarest and most aggressive is anaplastic thyroid cancer.

How is thyroid cancer treated? It starts with making the correct diagnosis — in fact over 90% of nodules removed at surgery turn out not to be cancer. We determine the type, the size, and whether it has spread. Treatment usually means removing the thyroid, followed in some papillary and follicular cancers by radioactive iodine, and then keeping the TSH a little lower than normal, which helps prevent the cancer from growing.

Part 4 — Radiofrequency ablation (RFA)

What is radiofrequency ablation (RFA)? For a long time surgery was the only option; now there is another. Radiofrequency ablation is a minimally invasive treatment that has been available for over 26 years in South Korea and more than 10 years in Egypt, among other countries, and is now being offered in Kenya. Under ultrasound guidance, a thin electrode delivers a controlled amount of heat into the nodule; the cells die and the body gradually clears them, and the nodule shrinks. The aim is not to remove the thyroid, but to relieve symptoms — cosmetic concern, pressure, difficulty breathing, a voice change — while preserving the gland. It is used mainly for nodules that are not cancer, though it has recently been approved for certain selected papillary thyroid cancers.

How does RFA make a nodule shrink? It is not cutting the nodule out. The heat treats the tissue, and the body slowly breaks it down and clears it over the following months — with up to 90–95% reduction in size by around three, six and twelve months.

Am I a candidate for RFA? First we confirm the nodule is not cancer, using fine-needle aspiration and core-needle biopsy. Good candidates have pressure in the neck, difficulty swallowing, or a cosmetic concern from an enlarged nodule; a nodule that is progressively enlarging; or simply a wish to avoid a cut, general anaesthesia, a hospital stay and the recovery of surgery.

Is RFA safe? Every procedure carries risk, but with radiofrequency ablation the risk of injury to nearby structures is under 2%, reduced further by careful patient selection and an experienced operator. We work under ultrasound guidance to avoid the airway, the nerves to the vocal cords and the blood vessels, and we can inject fluid to separate the nodule from the surrounding structures — making the procedure much safer. The goal is shrinkage, not removal.

Successful cases: before and after RFA In our own patients you can see the difference: a man with a thyroid nodule, and the effect a month later; a young woman with a nodule on the side of the neck; and others — each keeping their thyroid and going home the same day. Results do vary, and not every nodule shrinks this much.

Part 5 — When to get checked

When should you see a doctor about your thyroid? If you notice a thyroid nodule, or someone points one out, the next step is to see a doctor and have an ultrasound and risk assessment. Get your neck checked if you have difficulty swallowing or breathing, a changing voice, abnormal thyroid blood tests, or a family history of thyroid cancer. The message tonight: if you have a thyroid nodule, don't panic — but don't ignore it either. Get it assessed properly, and treated.