A study published in the journal Cancer Discovery has found that a blood test may be able to detect early on whether patients with advanced melanoma are relapsing. The work comes from scientists at the Cancer Research UK Manchester Institute, where the DNA shed by tumours into the bloodstream (circulating tumour DNA) was being studied from blood samples of advanced melanoma patients. It was found that tracking the levels of circulating tumour DNA could show whether a patient was relapsing. In addition to this, they discovered that new mutations in genes such as NRAS and PI3K could be the cause of the relapsing by allowing the tumour to become resistant to treatment.

Most melanoma patients respond to treatment at first but their cancer can become resistant within a year. It is hoped that these approaches will allow doctors to use circulating tumour DNA to tailor treatment for individual patients to get the best result.