Microbiome modification mooted as a future treatment for metastatic melanoma

Dermatologists from Germany and the UK have called for more research into the so called “obesity paradox” in melanoma survival. Studies have shown that obesity at the onset of systemic treatment of metastatic melanoma is associated with improved survival rates in males compared to patients with a ‘normal’ BMI. 

In a letter to the editor of the British Journal of Dermatology (BJD), the dermatologists have suggested that the gastrointestinal microbiome, the microorganisms in the gut, which amongst other things break down food and protect us from germs, may be an important mechanism behind this apparent paradox. Several recent studies have reported that the gut microbiome may influence a patient’s response to immunotherapy, improving the effectiveness of treatment. 

Twin studies have shown in the past that obesity is associated with a reduced overall gastrointestinal bacterial diversity. Subsequently the gut microbiome has been reported to potentially play an important role in the development of metabolic syndrome* and chronic inflammatory skin diseases, including psoriasis. 

If the link can be proven then it opens up the possibility of modifying the microbiome of individual metastatic cancer patients to improve their response to immunotherapies, thus increasing survival rates. 

Dr Ewan Langan, one of the authors of the letter, said, 

“At this stage, we are working with limited data; long-term, prospective data is lacking. However, this is an intriguing field of study, and more research should be done to solve this “obesity paradox” in melanoma survival. If it can be solved then perhaps the answer can open up new approaches for the treatment of cancer.”