BBC news correspondent Helen Fawkes, 41, was diagnosed with an advanced form of the disease on Christmas Eve, 11 years after she was first confirmed to have cancer.
Having fought the disease twice before, Ms Fawkes revealed she may be "dead by the summer".
In an emotional entry to her blog, she said: "I have advanced cancer, the kind you can never get rid of.
"All I can do now is try to destroy each tumour every time I get one. I'm not terminally ill but I will die a lot sooner than I ever imagined.
"The crazy thing is that I feel so well and yet I might be dead by the summer."
Ms Fawkes described the moment, during a check-up with medics, how she told of a slight pain near the scars of her previous cancer operations, prompting her consultant to send the journalist for a scan.
She was then called back on December 24th and told she had ovarian cancer.