Is Hashimoto’s Thyroiditis Linked to Thyroid Cancer? Here’s What You Need to Know 

Hashimoto’s thyroiditis is an autoimmune condition where immune cells attack your thyroid gland. As the most common cause of hypothyroidism, Hashimoto’s affects up to 7.5% of the population, with a particularly high prevalence among women.  

If you have been diagnosed with this condition, you might be wondering – can Hashimoto’s Thyroiditis lead to thyroid cancer? While there is no definitive link, the imbalance of thyroid hormones can increase the risk of thyroid cancer.  

Thankfully, early detection and timely treatment can mitigate this risk. In this article, we will explore what Hashimoto’s Thyroiditis is, its link to thyroid cancer, and the key preventive steps to protect your thyroid health.  

What Is Hashimoto’s Thyroiditis? 

Hashimoto’s thyroiditis, also known as chronic lymphocytic thyroiditis, is an autoimmune disorder where the immune system attacks the thyroid gland. The thyroid is a small butterfly-shaped organ near the base of the neck which produces hormones essential for metabolism. 

Chronic inflammation from the immune attack eventually disrupts thyroid function, meaning there are fewer thyroid hormones produced (hypothyroidism). This leads to various symptoms including: 

  • Enlarged thyroid (goiter) 
  • Fatigue and weakness 
  • Unexplained weight gain 
  • Increased sensitivity to cold 
  • Muscle aches and joint pain 
  • Dry skin and brittle nails 
  • Hair loss 
  • Impaired memory  
  • Depression  

If left untreated, it can cause complications like heart problems, infertility, and mental health issues. If you notice swelling in the neck or difficulty swallowing, consult a healthcare professional as soon as possible.  

Can Hashimoto’s Thyroiditis Cause Cancer? 

Hashimoto’s Thyroiditis can increase the risk of thyroid cancer, where 11-36% of thyroid cancer patients also have Hashimoto’s thyroiditis. 

Some studies described Hashimoto’s Thyroiditis as a double-edged sword. In the early stages, the inflammation from Hashimoto’s Thyroiditis can kill the cancer cells, providing some protection against cancer progression. Individuals with HT also tend to have less extrathyroidal extension, a condition where cancer cells grow beyond the thyroid gland. 

However, as inflammation persists, cancer cells adapt by gaining mutation to bypass inflammation-induced death and proliferate continuously, forming papillary thyroid cancer. This is the most common form of thyroid cancer, which begins in the follicular cells that produce thyroid hormones (T4 and T3) 

Several mechanisms may explain the increased risk of thyroid cancer among Hashimoto’s Thyroiditis patients: 

  • Hashimoto’s Thyroiditis leads to hypothyroidism, where lower thyroid hormones are produced. Normally, a high T4 level will signal the pituitary gland to stop producing thyroid-stimulating hormone (TSH). With hypothyroidism, this inhibition is lost, resulting in higher TSH levels that stimulates the body to create more thyroid cells, which can eventually lead to tumour formation.  
  • Chronic inflammation creates a favourable environment for cancer cells to survive and proliferate. For instance, it generates reactive oxygen species (ROS), which can cause DNA damage and mutations. This cause the cells to act abnormally, leading to cancer formation. 
  • A metastudy suggested that HT patients tend to have oncogenes, which are genetic mutations that cause cells to continuously divide. 

 

Warning Signs That Require Screening 

It can be difficult to distinguish Hashimoto’s Thyroiditis with cancer. However, any of these symptoms are abnormal and require medical attention as soon as possible: 

  • A lump or swelling in the neck region 
  • Persistent hoarseness or voice changes 
  • Difficulty swallowing or breathing 
  • Fatigue 
  • Unexplained weight gain 
  • Puffy face 
  • Muscle weakness and joint pain 
  • Irregular menstrual cycle 

While thyroid issues can happen to anyone, some risk factors can increase the odds of developing thyroid cancer from Hashimoto’s Thyroiditis: 

  • Sex: Women are more commonly affected by Hashimoto’s thyroiditis. For every man affected, about 7 to 10 women have HT as well. This could be due to iron deficiency when women reach menopause. Pregnancy could also affect the immune system, leaving women more vulnerable to autoimmune inflammation. 
  • Age: The incidence increases with age, with most cases diagnosed between 45 and 55 years old.  
  • Family history of thyroid cancer 
  • Previous history of goiters (enlarged thyroid) 

Early detection is key to timely treatment. If you experience a combination of the symptoms above or have a history of thyroid problems, consult a medical professional as soon as possible. 

 

Importance of Cancer Screening for Hashimoto’s Patients 

Early detection of thyroid cancer dramatically improves treatment outcomes and survival rates. This is especially important for patients with Hashimoto’s thyroiditis given their heightened risk.   

 There are several thyroid screening methods available: 

Blood Tests 

Thyroid function blood tests are typically the first step in screening. These tests help identify hormonal imbalances and detect the presence of autoimmune thyroid conditions. 

  • Thyroid-stimulating hormone (TSH): Produced by the pituitary gland, TSH signals the thyroid to produce thyroid hormones, which in turn suppresses TSH levels. Low levels of TSH could indicate hyperthyroidism, while high levels indicate hypothyroidism. 
  • Thyroxine (T4) and triiodothyronine (T3): T4 is a hormone that includes 4 iodine molecules. Once it is released into the bloodstream, the hormones lose one iodine to form T3, which regulates metabolism. Higher T4/T3 levels are signs of hyperthyroidism, while low levels indicate hypothyroidism. 
  • Thyroid antibodies: Elevated levels could indicate autoimmune conditions like Graves’ disease and Hashimoto’s Disease. 

 

Ultrasound scan 

Thyroid check

It is a non-invasive procedure that uses sound waves to obtain images of the thyroid, which helps to determine the size and appearance of any nodules. During the examination, you will lie on your back with your neck extended slightly backwards. A gel will be applied to the skin over the neck region to allow the transmission of sound waves. A transducer, which is a device that emits sound waves, will move gently over the neck region to capture images of the thyroid gland. The whole process will last from 15 to 30 minutes. 

 

Ultrasound-guided biopsy 

Also known as a thyroid fine-needle aspiration (FNA) biopsy, it uses ultrasound to guide a fine needle towards the thyroid to extract a small tissue sample of a suspicious thyroid nodule (larger than 1cm). FNA uses a finer needle than a normal biopsy, making it less invasive. 

No fasting is required before the procedure, though you may be advised to avoid blood thinners a few days before to reduce the risk of bleeding. Local anaesthetic may be given to minimise any discomfort. Like the ultrasound scan, a transducer is placed on the skin over the thyroid gland, showing an ultrasound image on a monitor that helps the doctor guide the biopsy needle towards the thyroid. A syringe is attached to the needle to extract a small tissue from a detected nodule, which is sent for lab analysis to determine if the nodule is benign or cancerous. 

 

How to Reduce Cancer Risk 

While we cannot prevent cancer risk completely, certain steps can lower the risk and protect your overall health: 

  • Exercise: Regular exercise 150 minutes per week. Be it taking the stairs or going on 5 minutes walks in between working hours goes a long way in strengthening your cardiovascular health. However, if you have a thyroid condition, consult your doctor first as certain thyroid medications may cause an extremely high heart rate. 
  • Minimise intake of processed foods or raw vegetables: They contain goitrogens that can disrupt balanced thyroid hormone production. If you have thyroiditis, cut down on gluten-rich foods like grains. Instead, focus on a mediterranean diet consisting of fruits, vegetables, beans, seafood, and nuts. 
  • Iodine-rich diet: Iodine helps the thyroid produce hormones. Adults are recommended to take 150 micrograms of iodine per day. Good sources include seafoods like tuna, as well as dairy products e.g. eggs and milk.  
  • Regular check-ups with an endocrinologist, especially if you have other thyroid abnormalities.  

 

Conclusion & Call to Action 

Hashimoto’s Thyroiditis causes inflammation, creating a favourable environment for cancer cells to grow. Hence, regular checkups on your thyroid is key to detecting early signs of tumour growth.   

Early detection saves lives – take control of your thyroid health by understanding the risks and staying aware of any changes in your body. If you suspect there is something wrong with your thyroid, book your thyroid screening with us today! 

 

Safeguard Your Health Today 

At Centre for Screening and Surgery, we prioritise delivering quality and comfortable early cancer screening and treatment using minimally invasive procedures. If you are concerned about your thyroid and are looking for a thyroid screening, call us to book an appointment today! 

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