Breakthrough on skin cancer: one simple jab

SCIENTISTS have developed a simple blood test to detect the most deadly form of skin cancer.

The test for melanoma, which would be conducted in GPs’ surgeries, could save thousands of lives.

At the moment patients have to rely on the judgment of doctors to decide whether or not a mole looks cancerous. If they think it is suspect, the patient is sent for a biopsy, where a small chunk of the mole is removed and examined for cancerous cells under a microscope. But doctors sometimes miss a melanoma, as it can be very difficult to distinguish a malignant mole from a benign one.

Now the company Oxford BioDynamics, a ‘spin-out’ from Oxford University, has come up with a way of testing if a patient has melanoma or not by taking a small blood sample from their arm.

Many people are diagnosed too late, when it has already spread to other organs. Melanoma kills three times more people than all other forms of skin cancer put together.

The firm’s test looks for changes in the way DNA is ‘packaged’ in particular skin cells, which signifies the presence of melanoma. These are cells called melanocytes, which create the skin pigment melanin. Some of them end up floating freely in blood, which are picked up in the 20ml test sample. The shape of their DNA is then analysed to look for patterns indicating melanoma, called ‘epigenetic signatures’.

The firm’s chief scientific officer Dr Alexandre Akoulitchev explained: ‘In the case of melanoma, there is a constant spread of invasive melanocytes from the primary cancer site. This test picks up traces of abnormality in the peripheral blood.’

The researchers first identified 15 signatures which were relevant by looking at 600 Australian patients, some of whom had melanoma and others who did not.

They then tested their approach with the help of doctors at the highly regarded Mayo Clinic in the US by looking at 119 American patients. Half these patients were known to have melanoma. Of the other half, 20 were known to be totally healthy; 20 had benign skin lesions like age-related spots; and 20 had non-melanoma skin cancers, which tend to be less deadly.

The firm’s testing method, called EpiSwitch, correctly spotted individuals with melanoma more than 80% of the time.

Dr Akoulitchev believes the test could save lives. He said: ‘Melanoma is one of the cancers where early diagnosis is essential.

‘Surgical intervention is one of the most effective ways of preventing the spread of melanoma to other parts of the body, if carried out early enough.’

However, he said there had been little interest from fellow companies or organisations like the NHS in developing it further.

‘For melanoma, early diagnosis is essential’