What we know and don't know about Kate's cancer diagnosis

Kate, the Princess of Wales, has disclosed that she has cancer and is undergoing chemotherapy — though in a video announcement Friday, she did not say what kind of cancer or reveal details of her treatment.

Here's what is known:

Kate had what was described as “abdominal surgery” on Jan. 16. The news wasn't announced until the next day, when Kensington Palace revealed that Kate was recovering from a planned operation.