Sarah Ferguson, 64, has been diagnosed with an aggressive form of skin cancer just six months after undergoing a successful operation to treat breast cancer.The latest health battle to rock the royals comes after Fergie, 64, had several moles removed from her body, one of which tested as a malignant melanoma - the most serious form of skin cancer that can spread to other areas of the body. Despite being in "good spirits" the Duchess of York has understandably found her second cancer diagnosis within six months "distressing." A spokesman for Sarah, Duchess of York said: "Following her diagnosis with an early form of breast cancer this summer, Sarah, Duchess of York has now been diagnosed with malignant melanoma.