Atopic Dermatitis, also called atopic eczema, is a chronic, more severe form of eczema, which is a common skin condition.1 Both are characterized by recognizable patches of scaly dry skin, redness, itching, and inflammation.
AD is a chronic relapsing condition, which means that it tends to come and go. People with AD have ongoing periodic “flares,” when symptoms are more severe, followed by periods of relief, when symptoms are less pronounced.2
What causes atopic dermatitis?
The causes of atopic dermatitis are not fully understood, but experts believe it originates from a combination of environmental and genetic factors. Functionally, it is likely the result of an overactive immune system responding with unnecessary strength to minor irritants or triggers. This causes inflammation and an overproduction of other immune factors, which in turn cause the redness, swelling, and itching that people with atopic dermatitis commonly experience.
Is there a connection between AD and skin cancer?
Because AD involves immune system problems and because many of the treatments for AD tamp down the immune system’s overactivity in the skin, people with the condition theoretically could have higher rates of skin cancer than the general population.3 In addition, because sunlight can help reduce symptoms of AD, people with the disease often try actively to expose their skin to the sun.4 Multiple studies have therefore attempted to look at the connection between skin cancer and AD. There is some disagreement about the results, but they are starting to converge on common themes.
Patients with AD have fewer moles
A large review paper looking at the collective results of multiple studies examining the linkages between AD and skin cancer found convincing evidence that people with AD have fewer moles than the general population.5 This result was also reported in MD Magazine.4 Moles can sometimes change to become skin cancer, and people with more moles can sometimes be at higher risk for developing skin cancer.
A lower melanoma risk
Several studies have also noted a slightly reduced risk of melanoma among people with AD. Statistically, for every 100 people in the general population expected to have melanoma, only 59 cases are seen among people with AD, according to one study examining Danish patients from 1977-2006.6
The review study quoted in MD Magazine showed a risk of 77 melanoma cases among people diagnosed with AD for every 100 cases in the general public. However, the authors note that there is a lot of difference in the designs and populations of the studies they examined, so they believe the connection deserves more study.5
Higher squamous cell carcinoma risk?
Evidence for higher risk among people with AD for other types of skin cancer is more clear-cut. Studies show elevated rates of squamous cell carcinoma and basal cell carcinoma (the non-melanoma types of skin cancer). A 2018 study conducted by the Mayo Clinic confirmed these results. For every 100 skin cancer cases in the general population, their results predicted 175 among people with AD.7
It is possible that people with AD have higher rates of diagnosis of these other skin cancers because they are being treated by healthcare providers who focus on their skin. Still, the authors of the Mayo Clinic study note, “Our finding of an association between a history of AD and SCC has clinical implications. As we continue to gather more data on this possible relationship, we can begin to counsel patients with AD on the importance of skin examinations and sunscreen use at a young age.”8
What is the Difference between Eczema and Atopic Dermatitis? National Eczema Association. https://nationaleczema.org/eczema/ Accessed March 15, 2018.
Atopic Dermatitis-Eczema. The Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/atopic-dermatitis-eczema/symptoms-causes/syc-20353273. Published March 6, 2018. Accessed March 15, 2018.
Lena Hagströmer, Weimin Ye, Olof Nyrén et. al., Incidence of Cancer Among Patients
With Atopic Dermatitis. Arch Dermatol. Vol 141, Sep 2005, pages 1123-7. Available at https://jamanetwork.com/journals/jamadermatology/fullarticle/398730 Accessed July 2, 2018.
Dava Stewart. What Is the Risk of Skin Cancer in Patients with Atopic Dermatitis? MD Magazine, September 7, 2016. Accessed July 2, 2018.
Gandini S, Stanganelli I , Palli D, et. al., Atopic dermatitis, naevi count and skin cancer risk: A meta-analysis. J Dermatol Sci. 2016 Nov;84(2):137-143. doi: 10.1016/j.jdermsci.2016.07.009. Accessed July 2, 2018.
Jensen AO , Svaerke C, Körmendiné Farkas D, et al., Atopic dermatitis and risk of skin cancer: a Danish nationwide
cohort study (1977-2006). Am J Clin Dermatol. 2012 Feb 1;13(1):29-36. doi: 10.2165/11593280-000000000-00000. Accessed July 2, 2018.
Janice Cho, Association between atopic dermatitis and squamous cell carcinoma: a case–
control study. International Journal of Dermatology. https://doi.org/10.1111/ijd.13857 Accessed July 2, 2018.
Atopic dermatitis associated with higher risk of skin cancer. HealthDay. December 29, 2017. https://medicalxpress.com/news/2017-12-atopic-dermatitis-higher-skin-cancer.html. Accessed July 2, 2018.