US President George W Bush will undergo a colonoscopy on Saturday as part of a routine examination, the White House said, according to dpa. Vice President Dick Cheney will assume power because Bush will be under anaesthesia during the procedure at the Camp David presidential retreat outside Washington, the White House said. Bush last underwent a colonoscopy in June 2002 and his doctors recommend he receive one every five years to check for colorectal cancer. Bush has not had any symptoms, White House spokesman Tony Snow said. Doctors removed polyps, which can be a precursor to cancer, from Bush before he became president. None were found in the 2002 examination that lasted two-and a-half hours. Snow said there is a "reasonable chance" polyps will be found this time given Bush's age and history. "If so, they'll be removed and evaluated microscopically," Snow said.
