A medical breakthrough is offering hope for the thousands of people whose genes make them more likely to get cancer.

Scientists have developed a new drug called Olaparib which only kills cancer cells and does not damage healthy ones.

Most other treatments such as chemotherapy kill both cancerous and healthy cells, causing serious side effects and weakening the patient.

Some people carry a fault in their genes known as the BRCA mutation which makes them more likely to get cancer.

For men the lifetime risk of developing prostate cancer doubles from 7 per cent to more than 15 per cent.

For women it is even worse. Their risk of developing ovarian cancer jumps from 2 per cent to 60 per cent, while their chance of getting breast cancer leaps from 10 per cent, to as much as 85 per cent.

Olaparib was developed by scientists at the Institute of Cancer Research in collaboration with the Royal Marsden Hospital and AstraZeneca.

It is still being tested but initial results have scientists excited.

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