The Princess of Wales is undergoing treatment for cancer

Kate Middleton says she was diagnosed with cancer, is undergoing chemotherapy The cancer was discovered in post-operative tests after her planned surgery.

Kate, the Princess of Wales, was diagnosed with cancer and is undergoing chemotherapy, she said in a video message released Friday, two months after she underwent "major" abdominal surgery.

The type of cancer has not been disclosed. According to Kensington Palace, Kate started a course of preventative chemotherapy in late February.

The announcement sparked an outpouring of support and comes as Kate's father-in-law, King Charles III, also undergoes cancer treatment.

"This of course came as a huge shock, and William and I have been doing everything we can to process and manage this privately for the sake of our young family," Kate, 42, said in the video, which was filmed at Windsor on Wednesday. "As you can imagine, this has taken time. It has taken me time to recover from major surgery in order to start my treatment."

The cancer was discovered in post-operative tests after her planned abdominal surgery in mid-January, she said to CNN