WASHINGTON — (CNN) Former President Jimmy Carter had a “small mass” removed from his liver during surgery Monday, his office said.

The surgery at Emory University Hospital “proceeded without issues, and the prognosis is excellent for a full recovery,” according to a statement from the Carter Center, the Atlanta not-for-profit the former president opened after leaving the White House.

Carter, 90, is the second-oldest living president but has led an active post-presidency, recently releasing a new autobiography, “A Full Life,” and promoting it in media appearances.

The former President has experienced some health concerns before. He cut a trip short to Guyana in May because he “was not feeling well.”

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