Jess Bravin reports on the Supreme Court.

Justice Ruth Bader Ginsburg returned to the bench today, keeping her promise to be back on the job for the first oral arguments since she underwent surgery for pancreatic cancer earlier this month.

After Ginsburg took her customary seat between Justices David Souter and Samuel Alito, the court got back to business without a word on its only female member’s ordeal. A dispute between the federal government and the Navajo Nation over coal mining royalties on the Indian tribe’s land was first up, and Ginsburg, her voice slightly scratchy, had lost none of her edge.

When Carter Phillips, the Washington lawyer representing the Navajo, seemed to backtrack from a position the tribe had taken earlier in the litigation, Ginsburg cut to the chase.

“You’re really saying you were wrong,” she chided.

According to the court, the tumor discovered in a January checkup turned out to be benign. But during the procedure surgeons found another, even smaller tumor that was cancerous and removed it. The disease, the court said, had not spread, and specialists say that the early detection and top-rate care Ginsburg received may make her one of the minority who live years after a pancreatic cancer diagnosis.

At a November event at Columbia Law School, where Ginsburg received a law degree in 1959 and later joined the faculty, the justice said her “hope and expectation” was to at least equal the tenure of another justice who joined the court at age 60, Louis Brandeis. Ginsburg, who turns 76 on March 15, would stay on the court until 2016 to match Brandeis, who stepped down at age 83.

At a Republican event in Kentucky, however, Sen. Jim Bunning suggested Ginsburg’s seat would soon be in play because she has “bad cancer. The kind that you don’t get better from,” the Louisville Courier-Journal reported. “Even though she was operated on, usually, nine months is the longest that anybody would live after (being diagnosed) with pancreatic cancer,” he said, the paper reported.

The court on Monday agreed to hear six new cases, including a challenge to the federal government’s effort to maintain a cross on a public nature preserve by transferring the land’s ownership to a private group.