Sarah Ferguson, Duchess of York, has been diagnosed with skin cancer. The 64-year-old author – who has daughters Princesses Beatrice and Eugenie with ex-husband Prince Andrew – has had several moles on her body removed, with tests finding one to be a malignant melanoma, just six months after she was treated for breast cancer. The duchess will now face “further investigations” to determine if the cancer has been caught early, but she is said to be “in good spirits”. Her spokesperson told The Sun: “Following her diagnosis with an early form of breast cancer this summer, Sarah, Duchess of York ha…