David Goldman, Associated Press
FILE - In a Sunday, Aug. 23, 2015 file photo, former President Jimmy Carter teaches Sunday School class at Maranatha Baptist Church in his hometown, in Plains, Ga. Former President Carter said Sunday, Dec. 6, 2015, that no cancer was detected in his latest scan.

ATLANTA — Jimmy Carter confirmed that his most recent brain scan showed no signs of cancer.

The former president said in a statement that he will continue to receive doses of Keytruda, a recently approved auto-immune drug to help his body seek out cancer cells in his body.

Carter says the scan showed no signs of the original cancer "spots" or any new ones.

Carter, 91, announced in August that he had been diagnosed with melanoma that spread to his brain. Doctors removed a portion of his liver and found four small tumors on his brain.

He received a round of radiation targeted at those tumors and regular doses of Keytruda. Carter has remained active during treatment, continuing his humanitarian work and volunteering with Habitat for Humanity.

Jimmy Carter's grandson said Sunday that no cancer was detected the last time the former president underwent a scan.

Jason Carter told The Associated Press in a text message that his grandfather on Friday "told me that the doctors couldn't find any cancer in his most recent scan."

In August, the 91-year-old Carter announced that he had been diagnosed with melanoma that spread to his brain. Doctors removed a portion of his liver and found four small tumors on his brain.

Carter received a round of targeted radiation at the tumors and also received doses of Keytruda, a newly approved auto-immune drug to help his body seek out any cancer cells appearing anywhere else in his body.

The former president apparently shared the good news on Sunday with those filling the congregation of Maranatha Baptist Church for one of his regular Sunday school lessons. Jill Stuckey, a church member who helps organize Carter's popular lessons, said in a phone interview that Carter told the congregation a brain scan this week showed no cancer.

Stuckey said people filling the sanctuary applauded after Carter's announcement, while she went into the church's back hallways to spread the word to members.

"Our prayers have been answered," Stuckey, also a close friend of the Carters, said. "I can't think of a better Christmas present."

Carter has remained active during treatment, volunteering on a building project with Habitat for Humanity and continuing to work at The Carter Center, the human rights organization he founded after leaving the White House.