Association of Hashimoto’s and Cancer. Does Hashimoto’s Increase the Chance for Cancer?
Inside: Association of Hashimoto’s and cancer, thyroid dysfunction with cancer. Why does Hashimoto’s increases the risk of cancer? Research-Backed Analysis of association of Hashimoto’s and Thyroid cancer, and Hashimoto’s and breast cancer!
Hypothyroidism is a common condition that has been affecting middle-aged females for ages now. But what has been changing with hypothyroidism over the course of several years is the cause of hypothyroidism.
Changing Causes of Thyroid Dysfunction
Initially, the major cause of hypothyroidism was iodine deficiency. In early 1900’s iodine was being linked to thyroid functioning. And it was determined that thyroid has very high concentrations of iodine in it, and that regions which have low iodine in their environment had higher prevalence of hypothyroidism.
So then there was worldwide initiatives of adding iodine to food so combat this hypothyroidism. Especially majority of the countries have iodized salt which gave people enough iodine in their diet and we thought we have conquered the major reason for hypothyroidism.
But since the addition of iodine to our food is the thyroid dysfunction gone? No! actually the incidence of thyroid dysfunction is increasing at a rapid rate.
This increase in Hyporthyrodism is now mainly because of the autoimmune thyroid condition called Hashimoto’s thyroid.
The incidence of Hashimoto’s thyroid condition is increasing at a rapid rate and it is estimated that its incidence is between 2 to 15 % in the general population.
The problem is that often Hashimoto’s disease is gone undiagnosed.
Even now the majority of the patients that come to see me have never had a test done to see if their hypothyroidism is due to Hashimoto’s or for another reason.
The reason being conventional medicine doesn’t have any specific treatment for Hashimoto’s disease.
The only treatment available is to wait till the inflammation in Hashimoto’s disease has destroyed the thyroid gland and then give people thyroid hormone for support.
But the underlying cause of Hashimoto’s Thyroiditis is never looked into and the chronic inflammation continues to destroy the thyroid gland and the medicine dosage keeps on increasing.
But the worst part is that even after taking the thyroid medicine often the symptoms don’t improve.
Hashimoto’s and Cancer
Most people think that having Hashimotos is just limited to having low thyroid hormone condition and taking levothyroxine as medicine will be enough.
But what people don’t understand is that — Hashimoto disease is an autoimmune condition, and once a person has one autoimmune condition there is a high chance of having another autoimmune disease too.
There have been studies that show that people with Hashimoto’s are at high risk for diabetes, lupus, RA and other conditions (references at the bottom of the article)
These studies looked into Thyroid Antibodies as markers to associate Hashimoto’s and Cancer. Since, presence of Thyroid Antibodies is a sure signal of Hashimoto’s.
But what is more concerning is that Hashimoto’s disease increases the risk of cancer development.
Having Hashimoto’s disease doesn’t only increase the risk of having thyroid cancer but it also increases the risk of having other cancers too.
Let’s look at the research studies that have looked into the association of thyroid antibodies (which indicate presence of Hashimoto’s Thyroiditis) and Cancer.
Thyroid antibodies and Thyroid Cancer
There are different kinds of thyroid antibodies like thyroglobulin antibodies ( Tgab), thyroid peroxidase antibodies ( TPO antibody), whose presence indicates positive Hashimoto’s thyroiditis. There have been several studies and one meta-analysis was done to summarize the findings from all of these studies.
The results showed that there is a strong association with the presence of thyroglobulin antibodies and having thyroid cancer.
In other words Hashimoto’s and cancer have a strong association.
So they did conclude that presence of TgaB antibody is an independent risk factor for thyroid cancer. TPO antibody also showed a similar association with thyroid cancer, but the association was not as strong as the TbAg antibodies.
There was another study done which was looking at people who had a biopsy done of the thyroid nodule to see if it was malignant or not.
In people where the results were indeterminate ( it means they were not clear), and they underwent surgery for removal of thyroid — it was seen that people with thyroid antibodies had a significantly higher risk for cancer as compared to people who didn’t have antibodies.
And it was also seen that people with thyroid antibodies had cancer which was more aggressive.
So these two studies clearly state that there is a higher risk of thyroid cancer in people with Hashimoto’s disease.
This increase in the risk of thyroid cancer among people with autoimmune thyroid disease is because of the inflammatory cells.
It has been seen that thyroid cancer particularly papillary thyroid cancer has inflammatory cell infiltrates. These include lymphocytes, macrophages, dendritic cells, and mast cells. And these similar cells are also hallmarked for the autoimmune thyroid disease, which is Hashimoto’s Thyroiditis.
So this immune dysfunction is thought to be contributing to thyroid cancer.
In other words Immune Dysfunction because of increased antibodies during Hashimoto’s increases risk of Thyroid Cancer.
Thyroid Autoimmunity and Breast Cancer
Breast cancer incidence is also increasing rapidly in the last decade. But is there a correlation between thyroid and breast cancer?
There was a study done on 867 breast cancer patients, and their thyroid status was checked.
The results showed a significant correlation in the presence of thyroid autoimmunity (Hashimoto’s) and breast cancer.
There has been some hypothesis that the link between the thyroid autoimmunity and breast cancer could be because of some shared similar antigens between the two glands, and also that breast cancer could be propagated by immune cells which might have been modified in case of thyroid autoimmune diseases.
Similar to thyroid cancer there have been studies that show that breast cancer also has immune cells present.
And so it’s not a surprise that the inflammatory autoimmune thyroid disease (like Hashimoto’s) increases the risk of breast cancer too.
This association between thyroid disorder and cancer means that inflammation does play a huge role in cancer development.
In fact, new cancer research is focusing on developing immunomodulator medicines to modify this inflammation and see if it can help with cancer treatment.
Summary of Does Hashimoto’s Increase the Chance for Cancer?
The takeaway message is that just treating people with levothyroxine to support their thyroid might not be enough when it comes to long term prevention of cancer caused by Hashimoto’s.
As the real issue that we are dealing with is — inflammation.
The underlying cause of inflammation can be different in different people but they need to be identified and worked on to reduce the occurrence of cancer.
So people with Hashimoto’s disease should focus on reducing inflammation and not just taking thyroid replacement through a pill.
Related Read to Hashimoto’s And Cancer:
Xiao Y, Zhou Q. Positive thyroid antibodies and risk of thyroid cancer: A systematic review and meta-analysis.Mol Clin Oncol. 2019 Sep;11(3):234-242. doi: 10.3892/mco.2019.1886. Epub 2019 Jun 21.
Adhami M, Michail P,Anti-Thyroid Antibodies and TSH as Potential Markers of Thyroid Carcinoma and Aggressive Behavior in Patients with Indeterminate Fine-Needle Aspiration Cytology.World J Surg. 2020 Feb;44(2):363-370. doi: 10.1007/s00268-019-05153-1.
Resende de Paiva C, Grønhøj C. Association between Hashimoto’s Thyroiditis and Thyroid Cancer in 64,628 Patients.Front Oncol. 2017 Apr 10;7:53. doi: 10.3389/fonc.2017.00053. eCollection 2017.
Rahman S1, Archana A2,Molecular Insights Into the Relationship Between Autoimmune Thyroid Diseases and Breast Cancer: A Critical Perspective on Autoimmunity and ER Stress.Front Immunol. 2019 Mar 1;10:344. doi: 10.3389/fimmu.2019.00344. eCollection 2019.