Vitamin D levels may affect body's response to cancer treatment: Study

Vitamin D levels may be key in determining the human body's response to anti-cancer immunotherapy, especially among people with advanced skin cancer, according to a study.

The findings, published online in the peer-reviewed journal CANCER, showed that for patients with advanced melanoma, it may be important to maintain normal vitamin D levels when receiving immunotherapy medications called immune checkpoint inhibitors.

Vitamin D has many effects on the body, including regulation of the immune system.

To see whether levels of vitamin D might impact the effectiveness of immune checkpoint inhibitors, the team analysed the blood of 200 patients with advanced melanoma both before and every 12 weeks during immunotherapy treatment.

A favourable response rate to immune checkpoint inhibitors was observed in 56.0 per cent of patients in the group with normal baseline vitamin D levels or normal levels obtained with vitamin D supplementation, compared with 36.2 per cent in the group with low vitamin D levels without supplementation.

Progressionafree survival -- the time from treatment initiation until cancer progression -- in these groups was 11.25 and 5.75 months, respectively.

"Of course, vitamin D is not itself an anti-cancer drug, but its normal serum level is needed for the proper functioning of the immune system, including the response that anti-cancer drugs like immune checkpoint inhibitors affect," said lead author Lukasz Galus, from Poznan University of Medical Sciences, in Poland.

"In our opinion, after appropriately randomised confirmation of our results, the assessment of vitamin D levels and its supplementation could be considered in the management of melanoma."

Melanoma is a disease in which malignant (cancer) cells form in melanocytes (cells that colour the skin). Melanoma can occur anywhere on the skin. Unusual moles, exposure to sunlight, and health history can affect the risk of melanoma.

A previous study, published in Melanoma Research earlier this year, showed that people who took vitamin D regularly were less likely to have had melanoma in the past or currently. They were also deemed by dermatologists to be less likely to develop melanoma in the future.