Washington  - Republican presidential candidate John McCain on Monday said his dermatologist had removed skin from his cheek in a routine check for skin cancer.

Questions have been circulating about McCain's health, in particular his apparent risk for skin cancer, since he secured the Republican party nomination for president.

"As I do every three months, (I) visited my dermatologist this morning," McCain said after discussing his support for off-shore drilling and nuclear power at a campaign event in sunny Bakersfield, California Monday. "She said that I was doing fine, took a small little nick from my cheek, as she does regularly ... just to make sure that everything is fine."

The Arizona senator has also suffered repeated cases of skin cancer that have been surgically removed four times since 1993, according to a statement from the Mayo Clinic in Arizona, which has been involved in McCain's treatment since 1992.

McCain carries a visible scar on the left side of his face from an invasive melanoma - a potentially serious form of skin cancer - that was removed in 2000. The other three cases of melanoma were non- invasive, and none of the four cases have recurred since they were removed.

The sample McCain's dermatologist took will undergo a biopsy, he said, taking the opportunity to warn listeners about the danger of sun- exposure.

"I want to, again, urge all Americans to wear sunscreen, particularly this summer. Stay out of the sun as much as possible," McCain said. "And if you ever have any slight discoloration, please go to your dermatologist or your doctor and get it checked up on."

McCain added that melanoma is a preventable occurrence of sun damage, but that damage people receive from the sun when they're young sometimes comes back later in life.

"And that's the end of my lecture from the American Dermatology Association today," he joked before leaving the event. (dpa)