Have eczema? It may reduce your skin cancer risk

Even an uncomfortable skin allergy has a good side to it. If we believe researchers, eczema caused by defects in the skin could reduce the risk of developing skin cancer.

According to a study, the immune response triggered by eczema could help prevent tumour formation by shedding potentially cancerous cells from the skin.

"We are excited as it establishes a clear link between cancer susceptibility and an allergic skin condition in our experimental model. It means that modifying the body's immune system is an important strategy in treating cancer," said professor Fiona Watt, director of Centre for Stem Cells and Regenerative Medicine at King's College London.

Eczema can result from the loss of structural proteins in the outermost layers of the skin, leading to a defective skin barrier.

During the study, the researchers compared the effects of two cancer-causing chemicals in normal mice and mice with the barrier defect (the "knock-out" mice).

The number of benign tumours per mouse was six times lower in "knock-out" mice than in normal mice.

The findings suggest that defects in the epidermal barrier protected the genetically engineered mice against benign tumour formation.

Researchers found that both types of mice were equally susceptible to acquiring cancer-causing mutations.

However, an exaggerated inflammatory reaction in "knock-out" mice led to enhanced shedding of potentially cancerous cells from the skin.

This cancer-protective mechanism bears similarities to that which protects skin from environmental assaults such as bacteria.

"I hope our study provides some small consolation to eczema sufferers - that this uncomfortable skin condition may actually be beneficial in some circumstances," Watt added.

This opens up new avenues for exploration while providing some comfort for those suffering from eczema, noted Mike Turner, head of infection and immunobiology at the Wellcome Trust.

The study, first to show that allergy caused by the skin defects could actually protect against skin cancer, was published in the journal eLife.