Selena Gomez opens up after receiving a 'life-or-death' kidney transplant

Gomez, 25, and her friend Francia Raisa, who donated the kidney, spoke to Today's Savannah Guthrie in an interview that will air in the US on Tuesday.

"My kidneys were just done," Gomez says. "And she volunteered and did it."

Gomez also underwent chemotherapy as part of her two-year fight against lupus, an autoimmune disease that often attacks the kidneys.

Gomez revealed her transplant via Instagram in September.