A thyroid nodule is a small lump that emerges on the neck. They are usually benign and not of clinical concern, particularly when they are found in older adults. Nonetheless, it is important to be assessed by a doctor to determine why it appeared.
There are many tests that can confirm whether the lump is benign or to check whether there are signs of malignancy. Specific cancer tests should be ordered if other symptoms are present so that the proper treatment can be initiated.
Most thyroid nodules do not cause any symptoms, and only a lump may be palpable on the neck. However, many patients may still report additional symptoms such as:
- Sore throat
- Neck swelling
- Difficulty breathing or swelling
- Weight loss for no apparent reason
- Tremors and nervousness
- Hoarseness or voice loss
If you suspect you may have a lump on your thyroid, you should see a doctor for assessment and testing. Check out other causes of a lump on the neck and what to do.
Tests for thyroid nodules
To diagnose a thyroid nodule, the doctor will first palpate the neck to feel the lump. From there, the doctor may order lab tests, like TSH, TS3, T4 anti-TPO and calcitonin, as well as imaging tests, like an ultrasound and scintigraphy.
After evaluating the results of these tests, the doctor may opt to order a fine needle aspiration of the thyroid, which collects a small sample of the nodule for lab analysis. The cells of this specimen are evaluated for characteristics of malignancy.
Read more about the thyroid tests that your doctor may order.
When should I worry about a thyroid nodule?
Some signs may indicate whether the thyroid nodule is malignant and if cancer is present, such as:
- The lump is hard and grows rapidly
- Patient’s age is under 20 or over 60
- The nodule has irregular borders
- There are vocal changes, like hoarseness or paralysis of the vocal cords
- A positive family history of thyroid cancer
- The patient has completed radiation therapy on the head and neck
There are studies that suggest that the higher the TSH level, the morel likely the nodule may be malignant. However, most people with thyroid cancer do not present with any changes in the bloodwork or in the biopsy, and it is only diagnosed after the lump is removed.
When patients present with just one thyroid nodule measuring at less than 1 cm, the doctor may not order any treatment, as long as there are no other signs of malignancy. The doctor may just order yearly ultrasounds and bloodwork to monitor the nodule.
Types of thyroid nodules
Thyroid nodules seen on a dopplar ultrasound are described using a classification system to determine whether they are benign or malginant. Classifying them also helps to guide treatment. Classification may be:
|Lagalla and cols classification||Chammas and cols classification|
|Type I: Lack of vascularization||Pattern I: Lack of vascularization|
|Type II: Pedinodular vascularization||Pattern II: Just peripheral vascularization|
|Type III: Peri and intranodular vascularization||Pattern III: Peripheral vascularization is greater than or equal to inner vascularization|
|---||Pattern IV: Inner vascularization is greater than peripheral vascularization|
|---||Pattern V: Just inner vascularization|
The endocrinologist can also describe the thyroid nodule as:
- Hypoechogenic: The mass is less dense than bone, which means the nodule is filled with fluid or air
- Isoechogenic: The solid mass is the same density as bone and is normally a circular shape
- Hyperechnogenic: The mass has a higher density than bone, which means the thyroid nodule has undergone calcification
Nodules with a higher vascularization within them have a higher chance of being malignant tumors.
Treatment is only ordered if the patient presents with symptoms, if the nodule shows suspicious signs for cancer, or if the nodule is over 3 cm. Common treatment options include:
- Surgery: Removal is usually recommended for nodules over 3 cm in size, or if the nodule is cancerous. It can also be indicated for large benign nodules that cause difficulty breathing or swallowing.
- Medications with levothyroixine: These are used in cases in which modules are causing hormonal changes and hypothyroidism.
Following surgery, it is important to treat with hormonal replacement therapy and to continue to be monitored at least twice a year by an endocrinologist.
What causes thyroid nodules?
The causes are still not totally known, however women are most affected as well as those with a positive family history for thyroid nodules.
How can thyroid nodules affect pregnancy?
Women with thyroid nodules do not experience more difficulty than others. However a thyroid nodule during pregnancy can cause changes to hormone production, which may require treatment with medication to help regulate thyroid function. Abnormal thyroid functioning can cause cognitive or physical disabilities in babies.