Library
All Topics
Psoriasis : peut-il se transformer en cancer ?

Can psoriasis turn into cancer?

Psoriasis is a skin disease characterised by skin covered in red patches and scales. According to some studies, individuals with psoriasis may be more likely to develop cancer. Is this really the case? This article provides some answers.

Summary
Published February 19, 2024, by Manon, Scientific Editor — 4 min read

What are the causes of the onset of psoriasis?

Psoriasis is a systemic and chronic inflammatory skin eruption. It presents itself as red and thick plaques that shed. Psoriasis is characterised by an excessive renewal and accumulation of epidermal cells, leading to local inflammation. This disease tends to affect adults, with a peak onset generally between 20 and 40 years of age. Approximately 30% of cases are said to be familial and appear during adolescence. When psoriasis appears after the age of 40, it is referred to as isolated or sporadic forms. However, it affects both sexes equally.

Skin inflammation is caused by a failure of the immune system. T lymphocytes produce inflammatory molecules (IL-17, IL-22, TNF-α, among others). These molecules stimulate the proliferation of keratinocytes. When the skin cell renewal period, which is normally about three weeks, is accelerated to just three days, this leads to an accumulation of immature keratinocytes on the skin's surface. The consequences are an increase in the thickness of the outer layer of the skin, known as the horny layer, and is referred to as hyperkeratosis.

Can psoriasis turn into cancer?

A study published in October 2019 in the journal JAMA Dermatology asserts that psoriasis increases the risk of developing cancer. The researchers found that the cancer risk rate for individuals with psoriasis is 1.18 times higher than that of healthy individuals. However, this risk can vary depending on the severity of the psoriasis. People with severe psoriasis have a 1.22 times higher risk of developing cancer compared to a population without psoriasis. On the other hand, no significant increase in cancer mortality risk was observed regardless of the severity of psoriasis. The main types of cancer developed include kidney cancer, colon cancer, liver cancer, oesophageal cancer, pancreatic cancer, and laryngeal cancer. Moreover, a severe form of skin cancer can appear, such as lymphoma or melanoma. In addition, the risk of developing basal cell carcinoma is twice as high as the risk of developing squamous cell carcinoma.

The cause of cancer development in a psoriasis patient is often associated with the treatment of the disease. This has an impact on the immune system, particularly the use of immunomodulators. They can increase the risk of cancer due to their mechanism of action which weakens the immune system. This results in a decrease in the body's ability to detect and eliminate cancer cells, promoting their multiplication. The treatment of psoriasis by phototherapy increases the risk of developing a squamous cell carcinoma or a basal cell carcinoma. Exposure to ultraviolet rays, particularly UVB rays, can damage the DNA of skin cells. When this is damaged, it can lead to genetic mutations which, in some cases, can lead to the development of cancer cells.

Note : This research is based on a collection of studies that were conducted independently and in different ways, accounting for the disparity in some of their results. Further studies are necessary to draw comprehensive conclusions about the link between psoriasis and the development of cancer.

Source

  • TRAFFORD A. M. & al. Association of psoriasis with the risk of developing or dying of cancer: A systematic review and meta-analysis. JAMA Dermatology (2019).

Diagnostic

Understand your skin
and its complex needs.