ATLANTA (WXIA) -- President Jimmy Carter received good news Tuesday from his cancer doctors at Winship Cancer Institute.

They tell him that recent tests have shown no evidence of new malignancy, and that his original problem is responding well to treatment.

In addition, they said further tests will continue.

Carter has been undergoing radiation treatment for cancer in four places in his brain since disclosing his diagnosis in August. While the 91-year-old former president has cut back his busy schedule in recent months, he continues work with the Carter Center and Habitat for Humanity, most recently participating in a one-day Habitat build in a Memphis neighborhood late last month.

PHOTOS |Jimmy Carter through the years