WASHINGTON — Supreme Court Justice Ruth Bader Ginsburg says she’s on her way to being “very well” following radiation treatment for cancer.

The 86-year-old justice was speaking Saturday at the Library of Congress National Book Festival in Washington. The event came a little over a week after Ginsburg disclosed that she had completed three weeks of outpatient radiation therapy for a cancerous tumor on her pancreas.

It was the fourth time since 1999 that Ginsburg has been treated for cancer. In announcing the news, the Supreme Court said in a statement that after the treatment there was “no evidence of disease elsewhere in the body.”

Ginsburg was treated for colorectal cancer in 1999, pancreatic cancer in 2009 and had lung cancer surgery in December.