Britain’s King Charles III and Queen Camilla walk with Canon Paul Williams as they arrive to attend a Sunday church service at St Mary Magdalene Church, in Sandringham, Norfolk, England on Sunday. PA via Associated Press

In his first statement on his recent cancer diagnosis, King Charles III expressed “heartfelt thanks” for the messages of support he received, while praising British cancer charities for their work.

“As all those who have been affected by cancer will know, such kind thoughts are the greatest comfort and encouragement,” the British monarch said in a statement released Saturday evening.

Charles also said it was “heartening to hear” that going public with his illness had helped raise awareness of the disease and promote the work of cancer charities. “My lifelong admiration for their tireless care and dedication is all the greater as a result of my own experience,” he said.

Although Buckingham Palace hasn’t yet disclosed what kind of cancer Charles has, his decision to eschew the usual royal practice of secrecy around health matters has already made him one of the world’s most famous cancer patients – and led many British people to look into their own risk of developing cancer.

According to Britain’s Guardian newspaper, the cancer charity Prostate Cancer UK has seen a substantial increase in the number of people using its online risk checker for prostate cancer since Charles’s diagnosis was made public.

The charity recently posted a link to the test, along with a message wishing the king the best with his treatment.

Buckingham Palace has said that Charles does not have prostate cancer, although doctors were alerted to an issue that led to his diagnosis while he was undergoing a procedure to treat a benign prostate enlargement last month.

Palace officials also have not said what kind of treatment he is receiving or whether it includes radiation or chemotherapy.

Another U.K. cancer charity, Macmillan Cancer Support, recently said it hoped that by “sharing his diagnosis so publicly,” the king would “encourage others to reach out for support if they are concerned about cancer.” The statement was reposted by the royal family on social media with a green heart icon – commonly used to express support.