BRITAIN'S King Charles has been diagnosed with a form of cancer and the 75-year-old will postpone his public duties while he undergoes treatment, Buckingham Palace said. Charles, who became king in September 2022 following the death of his mother Queen Elizabeth, is "wholly positive" about his treatment and looks forward to returning to full public duty as soon as possible, the palace said. Charles spent three nights in the hospital last month where he underwent a corrective procedure for a benign enlarged prostate. The palace said a separate issue of concern had been spotted during the hospital visit but did not give…