Actress Shannen Doherty has revealed in a heartbreaking interview that her cancer has returned.The Beverly Hills 902010 star, 48, spoke of the news on Good Morning America explaining that she had been diagnosed with stage four cancer last year and kept it hidden from the public. Shannen, who found fame in the original 90210 and supernatural series Charmed, was tearful as she explained she hadn't "properly processed" the news and that "it's a bitter pill to swallow in a lot of ways".