WASHINGTON (Reuters) - Justice Ruth Bader Ginsburg on Monday missed oral arguments for the first time since joining the U.S. Supreme Court in 1993 as the 85-year-old liberal jurist continues to recuperate from lung cancer surgery last month.

Chief Justice John Roberts addressed Ginsburg’s absence before the first of the day’s two arguments in cases before the court, saying she was “unable to be present today.” Ginsburg instead will work from home and use the case briefs and argument transcripts to participate in the cases, court spokeswoman Kathy Arberg said.

Ginsburg, the oldest member of the nine-justice court, underwent a surgical procedure called a pulmonary lobectomy on Dec. 21 at Memorial Sloan Kettering Cancer Center in New York to remove two cancerous nodules in her left lung and was released from the hospital on Dec. 25.

Monday’s arguments were the first on the court’s schedule since her surgery. After the procedure, the court said there was no evidence of remaining disease. It is not known whether Ginsburg will attend the court’s oral arguments in more cases on Tuesday and Wednesday.

It was the first time Ginsburg, one of the court’s nine justices, has missed oral arguments as a result of her various health scares, including two previous cancer diagnoses. Ginsburg participated in the court’s private meeting last Friday in which the justices voted on which new cases to take up, but was not present at the court, Arberg said.

As the oldest justice, Ginsburg is closely watched for any signs of deteriorating health. Ginsburg, appointed by Democratic President Bill Clinton, also is the senior liberal member of the court, which has a 5-4 conservative majority.

Ginsburg broke three ribs in a fall in November. The nodules were found as part of the tests the justice underwent after the earlier fall, according to the court.

Ginsburg was treated in 1999 for colon cancer and again in 2009 for pancreatic cancer but did not miss any argument sessions either time. In 2014, doctors placed a stent in her right coronary artery to improve blood flow after she reported discomfort following routine exercise. She was released from a hospital the next day.

She is viewed as something of a cult figure for U.S. liberals, known by the nickname “Notorious RBG,” after the late rapper Notorious BIG. A documentary film, “RBG,” and a feature film about her life, “On the Basis of Sex,” were released in 2018.

If Ginsburg were unable to continue serving, Trump could replace her with a conservative, further shifting the court to the right.