Source: Bang ShowbizSarah Harding fears she has skin cancer. The Girls Aloud star has reportedly undergone tests after having three potentially cancerous moles removed last Wednesday (17.10.12) - just two days before the group announced their greatest hits album 'Ten' and comeback tour - at a London Hospital and is now anxiously awaiting the results this week.Although the blonde beauty is "stressing" over the situation she has been reassured that things are looking very hopeful and that doctors believed they have removed the blemishes in time and do not think she will need any further treatment.A source told The Sun newspaper: "This is an incredibly stressful time for her. It's early days and the doctors are very positive - but the word 'cancer' is terrifying to hear and Sarah is naturally stressing about it."Luckily for the 30-year-old pop star she has been able to rely on the support of her Girls Aloud bandmates - Cheryl Cole, Kimberley Walsh, Nadine Coyle and Nicola Roberts.The four girls have told Sarah not to worry too much about the tests and instead try and focus on their tour. The source added: "The girls are completely behind her. Some of the fans have suggested she hasn't been enthusiastic about the tour, but the girls have told her not to stress because she'll only run herself down and make herself sick."In October 2011, Sarah checked into rehab to be treated for alcoholism and a dependence on sleeping pills.