LONDON (Reuters) - Britain's King Charles on Wednesday said his cancer diagnosis had been an experience that showed him "the very best of humanity", in a personal message celebrating the work of cancer support groups and charities.

Buckingham Palace said in February 2024 that Charles had been diagnosed with an unspecified form of cancer, detected in tests after a corrective procedure for an enlarged prostate.

He has been receiving treatment since and returned to public duties a year ago. Although updates on his condition have been rare, a Buckingham Palace source said in December that the treatment had been moving in a positive direction.

Charles used a message to attendees at a reception dedicated to the work of the cancer community to share his experiences of the disease.

"Each diagnosis, each new case, will be a daunting and at times frightening experience for those individuals and their loved ones," he said in the message published by the palace.

"But as one among those statistics myself, I can vouch for the fact that it can also be an experience that brings into sharp focus the very best of humanity."

Charles, 76, thanked charities for their work to raise funds for research, and reflected on the value of the human connection they offer patients in times of need.

"It has certainly given me an even deeper appreciation of the extraordinary work undertaken by the remarkable organisations and individuals gathered here this evening, many of whom I have known, visited and supported over the years," Charles said.

"And it has reinforced what I have long observed during these visits - that the darkest moments of illness can be illuminated by the greatest compassion."

(Reporting by William James, editing by Ed Osmond)