Lesion removed from McCain's nose malignant

Doctors said John McCain's lesion was "the earliest form of melanoma."

PHOENIX, Arizona (CNN) -- The lesion removed from Sen. John McCain's nose was malignant, the Arizona Republican's press secretary said Tuesday.

After the surgery late Monday afternoon, McCain had said it was a "non-malignant melanoma." The press secretary, Nancy Ives, said he "misspoke."

According to the American Academy of Dermatology, there is no such thing as "nonmalignant melanoma" -- melanoma by definition is malignant.

However, McCain's doctors at the Mayo Clinic Hospital in North Phoenix said the lesion was "in situ," meaning it hadn't spread beyond the original site where it was found. They called it "the earliest form of melanoma."

When melanoma is caught at its earliest stage, it has a 96 percent cure rate, according to the American Cancer Society.

McCain is to have plastic surgery this evening to "cover the defect left by the incision," his doctors said.

He is expected to be hospitalized overnight and released Wednesday.