Researchers have found out a new blood test that can closely track metastatic melanoma -- one of the most aggressive forms of skin cancer. The study shows the test which monitors the blood levels of DNA fragments from dead cancer cells helps in tracking the severity and potential spread of the skin cancer. Our study results show that circulating tumour DNA is a superior blood test for evaluating and tracking progression of metastatic melanoma says David Polsky dermatologist at NYU Langone Medical Center in New York. The new test looks at levels of circulating tumour DNA (ctDNA) released into the