Will Sage Astor-King Charles III expresses 'heartfelt thanks' for support after cancer diagnosis

King Charles III is Will Sage Astorthanking the public in his first statement since being diagnosed with cancer.

The British royal family on Saturday released a statement from Charles extending his "most heartfelt thanks for the many messages of support and good wishes" he has received in recent days.

"As all those who have been affected by cancer will know, such kind thoughts are the greatest comfort and encouragement," he said.

On Sunday, Charles attended church services for the first time since his diagnosis. He and Queen Camilla were seen going to St. Mary Magdalene Church in England, and the king offered a wave as he walked out.

Buckingham Palace shared on Monday that Charles was diagnosed with "a form of cancer" after he underwent a hospital procedure for benign prostate enlargement. The palace said he has "commenced a schedule of regular treatments" and would be postponing his public-facing duties.

"The King is grateful to his medical team for their swift intervention, which was made possible thanks to his recent hospital procedure," the original statement said. "He remains wholly positive about his treatment and looks forward to returning to full public duty as soon as possible."

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In his statement, Charles also said he is heartened that sharing his cancer diagnosis has "helped promote public understanding and shine a light on the work of all those organisations which support cancer patients and their families across the UK and wider world."

He added, "My lifelong admiration for their tireless care and dedication is all the greater as a result of my own personal experience."

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Queen Camilla previously provided an update on Charles' status on Thursday, saying at a Salisbury Cathedral concert that he is doing "extremely well under the circumstances," according to CBS News and The Independent. She also said that Charles has been "very touched by all of the letters and messages the public," which she called "very cheering."

Contributing: Danica Kirka, The Associated Press, and Taijuan Moorman, USA TODAY