Celiac Disease And Associated Cancers

Celiac disease is an autoimmune disease where your immune system attacks your own tissues in your gut (small intestine) when you eat gluten. This leads to damage to your gut, which prevents your body from properly absorbing nutrients from your food. 

Celiac disease can cause multiple symptoms, including diarrhoea, abdominal pain and bloating. Additionally, celiac disease has been linked to the development of several cancers. To manage the risk of associated cancers, it is important to diagnose celiac disease early and start properly managing it as soon as possible.

What is celiac disease?

Celiac disease is a serious long-term (chronic) autoimmune disorder, which causes an immune reaction to gluten, a protein found in some grains, such as wheat, barley and rye. These grains make up many staple foods of a traditional western diet, including:

• Pasta
• Cakes
• Breakfast cereals
• Most types of bread
• Some types of sauces
• Some ready meals

In addition, most beer is made with barley, wheat or rye.

If you have celiac disease, when you eat gluten, your immune system will make antibodies against it and send immune cells to destroy gluten. These immune cells and antibodies will attack the tiny, hairlike projections, called villi, that line the small intestine, damaging it.¹ This damage then impairs your ability to absorb nutrients from food and can lead to nutrient deficiencies. These nutrient deficiencies can then lead to other conditions, like microcytic anaemia caused by iron deficiency or macrocytic anaemia caused by folic acid and/or vitamin B12 deficiency.¹

Symptoms of celiac disease

Symptoms vary a lot between people, which makes it hard to identify it as celiac disease. Some people might experience gastrointestinal symptoms after eating gluten, but other will only start experiencing symptoms after developing nutritional deficiency.¹ Gastrointestinal symptoms include:

• Stomach pain
• Bloated stomach
• Gas
• Constipation
• Diarrhoea
• Fatty stools

Non-gastrointestinal symptoms include:

• Dermatitis herpetiformis
• Fatigue, or feeling tired
• Joint or bone pain
• Mental health issues, like depression or anxiety
• Neurological symptoms, like headaches, balance issues, seizures, or peripheral neuropathy
• Reproductive problems in people assigned female at birth, such as infertility, delayed start of or missed menstruation, or repeated miscarriages
• Symptoms involving the mouth, such as mouth sores, a dry mouth, or a red, smooth, shiny tongue

How many people have celiac disease?

It is estimated that celiac disease affects around 1% of people worldwide, however, only around 30% of those are actually diagnosed. Because the symptoms are so broad and are associated with several other disorders affecting the gut, many cases are not diagnosed.

In recent years, there has been an increase in the number of people diagnosed with celiac disease. This could be because of advances in diagnosing this disease. However, it is also thought that it could be caused by increased consumption of gluten in western diets, as well as the quality of gluten itself.¹

What causes celiac disease?

Celiac disease is considered to be a genetic disease, mainly linked to two genes: human leukocyte antigen (HLA) DQ2 and DQ8.² However, it has also been linked to multiple other non HLA genes.¹ 

If your close relative, such as a parent or sibling, has celiac disease, there is 10-15% chance that you will too. What’s more is if your identical twin has it, there is a 49%–83% chance that you will have it too. 

This suggests strong genetic link but that also environmental factors must also play a role as identical twins share the same genes, but not 100% get the celiac disease.³

Treatment for celiac disease

Unfortunately, the only effective treatment for celiac disease is a strict and lifelong gluten-free diet. This means avoiding all foods that contain wheat, barley, and rye, which can be a significant lifestyle adjustment. You might also need to take supplements to treat any nutritional deficiencies, or specific medications to treat conditions such as dermatitis herpetiformis.

Celiac disease and cancer

Celiac disease and increased risk of cancer

Celiac disease has been associated with an increased risk of developing certain cancers. Celiac disease is associated with chronic inflammation.⁴ Chronic inflammation can cause cell mutation and promote development of cancer.⁵ Therefore, chronic inflammation can be one of the ways that celiac disease promotes development of cancer. Additionally, celiac patients have a reduced number of natural killer cells, which are immune cells that kill cancer cells, compared to healthy individuals.⁴

It appears that the risk of cancer increases more when celiac disease is diagnosed later.⁶ The risk of developing cancer is highest in people diagnosed with celiac disease after age 60.⁷

Celiac disease and associated cancers

Celiac disease is associated with multiple cancers, such as⁴:

• Small intestine adenocarcinoma – this is a cancer that starts in the glandular epithelial cells (glands) lining your small intestine. Small intestine cancers are rare, but adenocarcinomas are the most common type of small intestine cancers. The risk of small intestine adenocarcinoma increases because of the inflammation in the small intestine, caused by the immune system reacting to gluten.
• Lymphomas – lymphomas are cancers of the lymphatic system that includes the lymph nodes (lymph glands), spleen, thymus gland and bone marrow. It can affect any area or organ in the body. People with celiac disease have a higher risk of developing a lymphoma, in particular, people with untreated CD have a higher risk of developing enteropathy-associated T-cell lymphoma (EATL). Adhering to a gluten free diet effectively reduces the risk of developing EATL.
• Oropharyngeal cancer – this is a cancer that affects your oropharynx in the middle section of your throat. It is relatively rare. Several studies found that the risk of oropharyngeal cancer is increased in people with celiac disease. However, the reason behind this increase is not well understood.
• Oesophageal cancer – it is the 10^th most common cancer in the world. It is a cancer of your oesophagus, which is a long tube that connects your mouth to your stomach so that food can be moved into the stomach. People with celiac disease have an increased risk of developing oesophageal cancer. When celiac disease is not treated, it can increase the risk of gastroesophageal reflux. Gastroesophageal reflux causes the acid from the stomach to travel up the oesophagus, damaging its tissues. The constant damage from the acid can lead to cell proliferation and ultimately cancer.
• Colorectal cancer – it is the 3^rd most common cancer in the world. It is estimated that 10% of all cancer cases worldwide are colorectal cancer. It affects the colon (large intestine) or rectum. Some studies have shown that people with celiac disease also have an increased risk of colorectal cancer.⁸ However, other studies did not identify an increased risk of colorectal cancer.⁹ Therefore, it is not conclusive if celiac disease increases the risk of colorectal cancer. It has been noticed that people with celiac disease have a reduced Bifidobacterium count in their faeces, which has anticancer properties, which could be a potential link between celiac disease and colorectal cancer.⁴

Can the associated cancers be prevented?

Luckily, strict adherence to gluten-free diet leads to complete healing of small intestine tissues in a large number of people with celiac disease.⁴ Several studies have indicated that following a strict gluten-free diet has a protective role against cancer and reduces the risk of developing associated cancers.⁴ 

On the other hand, it appears that if people do not follow a strict gluten-free diet, it can increase the risk of developing associated cancers.⁴ This is one of the reasons why it is important to stick to the gluten-free diet if you have celiac disease.

Summary

Celiac disease is a chronic autoimmune disease, in which your immune system has a bad reaction to consuming foods containing gluten. Your immune system produces antibodies against gluten and sends off cells to destroy it. However, it is the lining of your small intestine that gets destroyed. This affects your ability to absorb nutrients from food and can lead to deficiencies and deficiency associated conditions, such as anaemia. 

Celiac disease can cause multiple symptoms, however, people will experience different ones. Some will experience gastrointestinal symptoms, such as bloating and stomach pain, while others will experience non-gastrointestinal symptoms, such as fatigue and mouth sores. Celiac disease has been associated with an increased risk of multiple cancer, such as small intestine adenocarcinoma, lymphoma, oropharyngeal cancer, oesophageal cancer and colorectal cancer. The best way to reduce your risk of developing cancers associated with celiac disease is by adhering to a strict gluten-free diet.