WASHINGTON - Former US President Jimmy Carter announced Wednesday he has cancer, which was discovered during surgery last week to remove a mass in his liver.

Carter, 90, underwent the procedure Aug. 4 at Emory University Hospital in Atlanta, Georgia, according to media reports. “Recent liver surgery revealed that I have cancer that now is in other parts of my body,” he said Wednesday in a statement posted to the Carter Center website. “I will be rearranging my schedule as necessary so I can undergo treatment by physicians at Emory Healthcare. A more complete public statement will be made when facts are known, possibly next week.

Carter is the second-oldest living U.S. president behind George H.W. Bush, who is about four months older. Bush dealt with a broken neck vertebra in July. Carter’s surgery follows the publication of his book, “A Full Life: Reflections at 90,” which was described by a reviewer as a warm memoir of Carter’s youth alongside an assessment of the issues he tackled as the 39th president of the United States.

In his retirement, Carter has maintained good health and traveled regularly.

So far this year he has visited places in the Middle East and South America, although he cut a May trip to Guyana short due to feeling ill.