Republican Sen. John McCain announced on Monday that he had had a small patch of skin removed from his right cheek and biopsied as part of a routine dermatological checkup.

Mr. McCain, 71, who has had four melanomas, a possible fatal form of skin cancer, informed reporters on a presidential campaign visit to an oil rig that the procedure had been performed on Monday morning in Arizona and that his dermatologist said that he was doing well.

At first, John McCain had a small bandage on his upper right cheek, close to his temple, but he had taken it off by the afternoon, uncovering a small, dark spot. However, the left side of his face continues to be swollen and scarred in consequence of the surgery he has suffered eight years ago in order to remove the cancer and lymph nodes.

The senator recommended people to avoid the sun as much as possible and use sunscreen, especially during the summer. “But I want to again urge all Americans to wear sunscreen, particularly this summer, stay out of the sun as much as possible and if you ever have any slight discoloration, please go to your dermatologist or your doctor and get it checked up on,” Mr. McCain said, as quoted by the New York Times.

John McCain said that the biopsy results would be complete on Tuesday. Asked whether voters should be concerned about his health conditions, Mr. McCain declared in an interview with CNN’s Larry King Live that there is no reason of worry, as reported by the Associated Press.

The campaign also released a statement from Michael Yardley, the chairman of public affairs at the Mayo Clinic in Scottsdale, Arizona, who explained that the biopsy was requested as a safety measure and “is a routine minor procedure.”