The 75-year-old monarch began his cancer treatment Monday.
King Charles III, 75, has been diagnosed with a form of cancer, Buckingham Palace says.
“During The King’s recent hospital procedure for benign prostate enlargement, a separate issue of concern was noted,” Buckingham Palace said in a statement.
The statement did not say what type of cancer was found.
The 75-year-old monarch has been advised by doctors to postpone his public engagements. “Throughout this period, His Majesty will continue to undertake State business and official paperwork as usual,” the statement read.
Dr. David Berlach, Chair of the Radiation Oncology Division at Maimonides Medical Center in New York, spoke with Inside Edition about the case.
"Anyone of King Charles' age who is diagnosed with cancer, you always get concerned, but hopefully it is a curable form of cancer and that he'll be able to beat it," Berlach says.
Prince Harry is reportedly preparing to return to the United Kingdom to be at his father's side.
King Charles was released from the London Clinic last week after spending three nights at the hospital. He begins his cancer treatment on Monday.
"The word is shock. The word is devestation. The word is also sadness depending on who you speak to," CBS News foreign correspondent Ramy Inocencio says. "People are saying that even though this is the king of the United Kingdom, he's also a father. He's also a grandfather and that anyone who has a diagnosis of cancer will be received with sympathy, with empathy here."
The statement from the palace says King Charles, “Has chosen to share his diagnosis to prevent speculation and in the hope it may assist public understanding for all those around the world who are affected by cancer.”
The extended absence of King Charles leaves the royal family with few members to handle public duties. Princess Kate is recovering from her recent surgery, leaving Queen Camilla and Prince William, who will resume his public schedule on Wednesday.
