Is there a general link between autoimmune disease and cancer?
Yes, but the overall effect is modest. A massive 2021 study of nearly 480,000 people in the UK found that having an immune-mediated disease was associated with an 8% higher risk of developing any cancer over the follow-up period [1]. This means that while the risk is real, it's not a dramatic increase for everyone. Another large Finnish study confirmed this pattern, showing that the risk of cancer was about twice as high in the first year after an autoimmune diagnosis, but this dropped to only a 5% increased risk ten years or more after diagnosis [6]. This suggests that some of the early risk might be due to increased medical surveillance (finding cancers that were already there) or the active inflammation itself.
The key takeaway is that the link is not uniform. The type of autoimmune disease and the specific cancer matter enormously. For instance, while the overall risk is small, certain autoimmune diseases carry a very high risk for specific cancers, as detailed in the next section.
Which autoimmune diseases carry the highest cancer risk?
The link is strongest when the autoimmune disease directly affects the organ where the cancer develops. The large UK Biobank study found that autoimmune hepatitis was associated with a 21-fold higher risk of liver cancer, and celiac disease with a nearly 7-fold higher risk of small intestine cancer [1]. Similarly, primary biliary cholangitis, an autoimmune disease of the bile ducts, was linked to a 42-fold higher risk of liver cancer [1]. This pattern strongly suggests that chronic inflammation in a specific organ can directly drive cancer formation in that same tissue.
Other autoimmune diseases are linked to a broader range of cancers. For example, the same study found that idiopathic thrombocytopenic purpura (ITP), a bleeding disorder, was associated with a nearly 7-fold higher risk of liver cancer and a 12-fold higher risk of liver cancer in a separate analysis [1]. Rheumatoid arthritis (RA) has been linked to a 21% increased risk of bladder cancer in a genetic study [2], and psoriasis was associated with a 31% higher risk of anal cancer in a study of the elderly [3]. These findings show that the effects can extend beyond the primary organ system.
What causes the increased cancer risk?
The reasons are complex and likely involve a combination of factors. The most obvious is chronic inflammation. The immune system's constant, misguided attack on the body's own tissues creates an environment of cellular stress and repair that can lead to DNA damage and cancer. This is supported by the strong link between organ-specific autoimmune diseases and cancers in the same organ [1].
However, it's not just the disease itself. The treatments used to manage autoimmune diseases, which often suppress the immune system, can also increase cancer risk. A 2025 study analyzing drug safety reports found that several immunosuppressive drugs, including TNF inhibitors and interferon beta-1a, were associated with increased reports of breast cancer in women with autoimmune diseases [4]. This highlights a difficult balance: controlling the autoimmune disease may inadvertently raise the risk of certain cancers.
Finally, there may be shared genetic or environmental factors that predispose someone to both an autoimmune disease and cancer. A 2023 study using genetic analysis found that while some autoimmune diseases like rheumatoid arthritis and multiple sclerosis appear to causally increase bladder cancer risk, others like lupus and type 1 diabetes did not show a clear genetic link [2]. Another study found no strong genetic evidence for a causal link between several autoimmune diseases and breast cancer [5], suggesting that shared genetics may not be the primary driver for all cancer types.
About These Sources
This answer is built on 6 peer-reviewed studies — published from 2021 to 2025, 2 from 2024 or later, 5 in Q1 journals, collectively cited 143 times — selected as the most relevant from 15 studies that passed quality screening, drawn from 52 papers retrieved from a database of over 500 million.
Sources used in this answer
Immune-Mediated Diseases Associated With Cancer Risks
In a large UK cohort (n=478,753), having an immune-mediated disease was associated with an 8% higher risk of total cancer, with much higher risks for organ-specific cancers (e.g., autoimmune hepatitis with a 21-fold risk of liver cancer).
Autoimmune diseases and the risk of bladder cancer: A Mendelian randomization analysis
A Mendelian randomization study found genetic evidence that rheumatoid arthritis and multiple sclerosis causally increase the risk of bladder cancer (by 21% and 10%, respectively).
Abstract B008: Autoimmune disease and the risk of anal cancer in the U.S. elderly population
A US case-control study of the elderly found that having any autoimmune condition was associated with a 12% increased risk of anal squamous cell carcinoma, with the strongest links for sarcoidosis (2-fold) and lupus (1.9-fold).
Bridging pharmacovigilance and genetic insight: investigating drugs and indications for breast cancer risk in women with autoimmune diseases
An analysis of the FDA Adverse Event Reporting System found that several immunosuppressive drugs (e.g., interferon beta-1a, natalizumab) were associated with increased reports of breast cancer in women with autoimmune diseases.
Investigation of the causal relationship between breast cancer and autoimmune diseases: A bidirectional mendelian randomization study
A Mendelian randomization study found no strong genetic evidence for a causal relationship between several autoimmune diseases (e.g., Graves' disease, psoriasis) and breast cancer risk in a European population.
Abstract 29: Autoimmune diseases and the risk of cancer
A Finnish population-based study found that cancer risk was doubled in the first year after an autoimmune disease diagnosis, but remained elevated (5% higher) even 10 years later for conditions like lupus and Crohn's disease.