Carter, 90, is scheduled to hold a news conference at 10 am local time at the Carter Center in Atlanta. Carter announced August 12 that liver surgery found cancer that has spread to other parts of his body.
The three-sentence statement did not identify the cancer or say where it originated. Doctors not involved in treating Carter have said those characteristics could determine Carter's options for treating the cancer.
His father, brother and two sisters died of pancreatic cancer. His mother also had the disease. Carter's health has been closely watched this year.
He cut short an election monitoring trip to Guyana in May. A spokeswoman said he did not feel well and Carter later said he had a bad cold.
The center announced Carter had a small mass removed from his liver August 3. Nine days later, Carter said that surgery revealed the cancer.
Carter was the nation's 39th president, advancing as a virtual unknown on the national stage to defeat President Gerald Ford in 1976.
But several foreign policy crises, in particular the Iran hostage crisis, crushed his bid for re-election and Ronald Reagan swept into the White House.