Don't freak out! It's not that serious.
Fortunately, the cancer has been diagnosed in its very early stages and that means it can be treated and Christina can recover fully.
Her spokesperson issued a statement saying:
"Christina Applegate was diagnosed with an early form of breast cancer. Benefiting from early detection through a doctor ordered MRI, the cancer is not life threatening. Christina is following the recommended treatment of her doctors and will have a full recovery. No further statement will be issued at this time."

We wish you lots of health and hope you'll get well really soon!