LONDON -- Kate, the Princess of Wales, said Friday she has cancer and is undergoing chemotherapy.
The came after weeks of speculation spread on social media about her whereabouts and health since she was hospitalized in January for an unspecified abdominal surgery.
"At the time, it was thought that my condition was non-cancerous," she said in the video. "The surgery was successful. However, tests after the operation found cancer had been present. My medical team therefore advised that I should undergo a course of preventative chemotherapy and I am now in the early stages of that treatment."
Kate, 42, hadn't been seen publicly since Christmas until video surfaced this week of her with her husband, Prince William, heir to the throne, walking from a farm shop near their Windsor home.
Kensington Palace had given little detail about Kate's condition beyond saying it wasn't cancer-related, the surgery was successful, and recuperation would keep the princess away from public duties until April.
The news is another shock for the royal family since the announcement last month that King Charles III was being treated for an unspecified type of cancer that was caught while undergoing a procedure for a benign enlarged prostate.
Charles, 75, has withdrawn from public duties while he has cancer treatment, though he's appeared frequently in photos carrying on meetings with government officials and dignitaries and was even seen going to church.
Kate, on the other hand, had been out of view, leading to weeks of . Attempts to put rumors to bed by releasing a photo of her on Mother's Day in the U.K. surrounded by her three smiling children backfired when the Associated Press and other news agencies retracted the image because it had been manipulated.
Kate the next day acknowledging she liked to "experiment with editing" and apologizing for "any confusion" the photo had caused. But that did little to quell the speculation.
Even the footage published by The Sun and TMZ that appeared to show Kate and William shopping sparked a new flurry of rumor-mongering, with some armchair sleuths refusing to believe the video showed Kate at all.
Earlier this week, a British privacy watchdog said it was investigating a report that staff at the private London hospital where she was treated tried to snoop on her medical records while she was a patient for .
The former Kate Middleton, who married William in a fairy-tale wedding in 2011, has boosted the popularity and appeal of the British monarchy worldwide more than any royal since Princess Diana.
The princess is the oldest of three children brought up in a well-to-do neighborhood in Berkshire, west of London. The Middletons have no aristocratic background, and the British press often referred to Kate as a "commoner" marrying into royalty.
Kate attended the private girls' school Marlborough College and then University of St. Andrews in Scotland, where she met William around 2001. Friends and housemates at first, their relationship came to be in the public eye when they were pictured together on a skiing holiday in Switzerland in 2004.
Kate graduated in 2005 with a degree in art history and a budding relationship with the prince.