Thyroid nodules refer to thyroid masses formed by excessive growth of normal thyroid tissue, and the majority of cases have an unknown cause, possibly related to excessive hormonal stimulation. Women have a higher chance of developing thyroid nodules compared to men, especially middle-aged women.

When thyroid nodules become enlarged, they can protrude in the neck, giving rise to a “goiter” appearance. As the thyroid gland is located in front of the trachea, severe goiter can compress the trachea, affecting breathing. The thyroid gland may also extend to the position behind the clavicle, obstructing the entrance to the chest, leading to breathing difficulties and complications such as impeded venous blood flow from the head and neck. If a patient has multiple nodules in the thyroid gland, it is referred to as multinodular goitre.

Most thyroid nodules are benign, but it is essential for doctors to clinically differentiate between benign thyroid nodules and malignant thyroid cancer.

Blood tests: Thyroid Function Tests

Thyroid function tests evaluate the secretion of thyroid hormones in the body and can provide results through blood tests. Thyroid function tests include the measurement of triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) levels. These tests help doctors differentiate between hyperthyroidism, hypothyroidism, or normal thyroid function.

In general, patients with thyroid nodules and multinodular goitre have normal thyroid function, so blood tests for thyroid function usually come back normal. Thyroid function tests primarily assist doctors in differentiating other possible diagnoses that may cause a goiter, such as Graves’ disease.

For the diagnosis of thyroid nodules, doctors typically arrange the following three examinations:

Clinical examination

Through observation and clinical examination, doctors can inquire about the patient’s medical history, family history, relevant symptoms, etc. Clinical palpation allows doctors to determine whether the patient has thyroid swelling, whether the swelling is uniform and symmetrical, whether there are other hard masses or lymph node swelling in the neck, whether the trachea is compressed due to thyroid swelling, and so on. After initial assessment, the doctor may arrange further examinations such as thyroid ultrasound or thyroid fine-needle aspiration (FNA).

Thyroid ultrasound

Thyroid ultrasound is a non-invasive examination. During the examination, the doctor applies gel to the patient’s neck and uses an ultrasound probe to obtain real-time images of the thyroid. The doctor captures corresponding images during the examination for evaluation. Thyroid ultrasound helps the doctor assess the size of the thyroid, the size and nature of thyroid nodules, blood flow around the nodules, identification of calcifications, differentiation between thyroid cysts and nodules, evaluation of lymph node swelling in the neck, and more.

Based on the ultrasound appearance, thyroid nodules are classified into three major categories: solid nodules, cystic nodules, and mixed nodules (combining features of both solid and cystic). Solid nodules have a higher chance of being malignant and require special attention.

Pathological examination

After evaluation, the doctor may request a pathological report to provide further information for diagnosis. The most commonly used method is ultrasound-guided fine-needle aspiration (FNA). During the procedure, the doctor uses ultrasound to locate the lesion and then extracts a small amount of cells from the nodule using a fine needle (typically 21 or 23 gauge). The patient may experience mild discomfort during the procedure, and there will only be a single needle puncture wound. The extracted cells are sent to the pathology department for analysis. Pathologists examine the characteristics of the cells under a microscope to determine their type. The doctor pays special attention to features indicating the presence of cancer cells. All findings are detailed in the pathology report. In addition to recommending FNA for the thyroid nodule, the doctor may also suggest FNA for enlarged neck lymph nodes if necessary.

After the clinical examination, thyroid ultrasound, and pathological examination, the doctor can generally make a diagnosis, determine the nature of the thyroid lesion, and formulate a treatment plan for the patient.

Other examinations

Additional tests may include computed tomography (CT) scans, chest X-rays, and electrocardiograms.

Thyroid nodules or multinodular goitre are generally treated with surgery. Medication therapy is typically ineffective in these cases, and surgical intervention is necessary for a cure.

Surgical Treatment

In general, thyroid nodules or multinodular goitre can be managed through observation. However, surgery may be considered in the following situations:

1. Enlarged thyroid causing cosmetic concerns due to a noticeable neck swelling.
2. Enlarged thyroid compressing the trachea, affecting breathing.
3. Enlarged thyroid extending behind the clavicle (collarbone).
4. Presence of cancer cells in the thyroid nodules or a possibility of nodules progressing into cancer.

Depending on the number and distribution of thyroid nodules, your doctor may recommend either total thyroidectomy or hemithyroidectomy.

Both surgeries are performed under general anesthesia. The surgeon will make an incision in the patient’s neck, usually hidden within natural neck creases, to minimize the visibility of post-operative scars.

Total thyroidectomy involves removing the entire thyroid gland. Since the thyroid gland is responsible for producing thyroid hormones in our body, patients will need to take thyroid hormone replacement medication daily after the surgery. The procedure for total thyroidectomy typically takes around 2.5 hours.

On the other hand, hemithyroidectomy involves removing the side of the thyroid gland with nodules while preserving the other side. The remaining thyroid can effectively compensate for the entire thyroid’s function, so patients do not need to take medication after the surgery. The procedure for hemithyroidectomy usually takes around 1.5 hours.

Radiofrequency Ablation (RFA)

Radiofrequency Ablation (RFA) is a relatively new minimally invasive method for treating thyroid nodules. It utilizes radiofrequency energy to destroy the nodules. During the treatment, the doctor will inject a small amount of local anesthesia into the skin and then use ultrasound guidance to insert a radiofrequency needle into the nodule. The high-energy radiofrequency will burn and destroy the nodule tissue, which will be absorbed by the body over time. The entire treatment process takes a few minutes, and the advantage of this procedure is that it does not leave visible scars on the skin, making it more aesthetically pleasing compared to traditional surgery. RFA is suitable for smaller-sized thyroid nodules.