US President George W. Bush had five polyps removed during a "routine" colon cancer check on Saturday, but the White House said there was no cause for concern and that he had resumed power after a brief handover to Vice President Dick Cheney.
"None appeared worrisome," White House spokesman Scott Stanzel said of the five growths that were removed during the approximately half-hour long procedure, adding that "all of them were small."
The polyps -- each described as less than 1cm in size -- are being sent for routine microscopic examination and the results are expected in 48 to 72 hours, or tomorrow at the earliest.
The results will determine the final diagnosis and recommendations for future treatment, the spokesman said.
Stanzel said the procedure was a preplanned, "routine surveillance colonoscopy" and that doctors were not surprised by what they found.
"They did indicate they were all small, some very small and I would say that is why surveillance ... has become a part of the colorectal cancer screening process," he said, adding that the procedure was scheduled "out of an abundance of caution."
The 61-year-old president, who has twice before had non-cancerous growths removed from his colon, was "in good humor and will resume his normal activities at Camp David," he said.
The president ate breakfast, played with his dogs and went for a walk after the procedure and also planned to go for a bike ride later in the afternoon, Stanzel said.
The White House released a photograph taken after the procedure showing Bush in a jacket and blue jeans walking on Camp David grounds together with his chief of staff Joshua Bolten and his dog.
Bush was sedated during the procedure, in what Stanzel described as "conscious sedation."
"Bush was asleep but responsive during the colon check," Stanzel said.
"It would be accurate to describe him as `under' but this was not a general anaesthetic," adding that the sedation, which used propofol, has a "rapid awakening effect."
After the operation, Bush spoke by phone to his wife, Laura, who is in Texas celebrating her mother's birthday, Stanzel added.
In all, Cheney was in charge of the country for two hours and five minutes.
Cheney, 66, spent that time at his residence on Maryland's eastern shore in what Stanzel described as a "routine Saturday morning."
It was only the third time in US history that a president made use of the Constitution's transfer of power to a vice president, a move that is possible under the 25th amendment.
The only other times were when Ronald Reagan underwent surgery for colon cancer on July 13, 1985, and when Bush underwent a previous colonoscopy on June 29, 2002, White House officials said.