Sarah Ferguson, Duchess of York, diagnosed with malignant ...

Sarah Ferguson, the Duchess of York, has been diagnosed with skin cancer just months after she battled breast cancer, her spokesperson confirmed Sunday. 

Ferguson, widely known as Fergie, announced she'd beaten breast cancer in a New Year's Eve post to social media. The new malignant melanoma diagnosis was detected when a dermatologist was removing and analyzing several moles while Ferguson was undergoing reconstructive surgery following her mastectomy, her spokesperson said. One of the moles was identified as cancerous.

Her spokesperson did not specify when the Duchess of York was diagnosed.

"She is undergoing further investigations to ensure that this has been caught in the early stages," her spokesperson said. "Clearly, another diagnosis so soon after treatment for breast cancer has been distressing but the Duchess remains in good spirits."

Ferguson emphasized the importance of checking the size, shape, color and texture of new moles for signs of melanoma, her spokesperson said.

Melanoma can be treated successfully if it is found early, according to the Mayo Clinic. However, it is one of the most dangerous forms of skin cancer. Melanoma accounts for just 1 percent of skin cancer cases, but the majority of skin cancer deaths, according to the American Cancer Society.

Ferguson, who used to be married to Prince Andrew, is mother to Princesses Beatrice and Eugenie of York.

She and her daughters have previously worked with the Teenage Cancer Trust. Princess Beatrice is patron of the British Skin Foundation and has worked with skin cancer patients.

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