ATLANTA — Civil rights icon and longtime U.S. Rep. John Lewis announced Sunday he is battling cancer.

Lewis, 79, said in a statement he learned from doctors he must be treated for pancreatic cancer. During a routine medical visit, he said, doctors discovered the stage 4 cancer.

“I have been in some kind of fight — for freedom, equality, basic human rights — for nearly my entire life. I have never faced a fight quite like the one I have now…” Lewis said in a statement. “So I have decided to do what I know to do and do what I have always done: I am going to fight it and keep fighting for the beloved community. We still have many bridges to cross.”

Lewis said he is “clear-eyed about the prognosis” and has been reassured by doctors that medical advancements have made the cancer treatable in many cases and the treatments aren’t as debilitating as they have been in the past.

Lewis said he does not plan to halt his work in Washington.

“To my constituents: being your representative in Congress is the honor of a lifetime. I will return to Washington in coming days to continue our work and begin my treatment plan, which will occur over the next several weeks,” Lewis said. “I may miss a few votes during this period, but with God’s grace I will be back on the front lines soon.”

The Alabama native has spent over three decades in the U.S. House and made his mark in history as a prominent figure in the civil rights movement. As a young activist, he faced the violence that has been part of the movement. Lewis was beaten as a Freedom Rider in 1961 and in 1965 was bludgeoned in Selma on “Bloody Sunday.”

The Atlanta Democrat has been re-elected to the U.S. House 16 times and became a champion of the Voting Rights Act of 1965. Lewis held the gavel this past month when the act re-upped by the Democratic House after being gutted by the Supreme Court in 2013.

Politicians, activists and friends took to social media after Lewis’ announcement, expressing well-wishes and sharing thoughts about the leader.

Former President Barack Obama, U.S. Speaker of the House Nancy Pelosi and Former President Bill Clinton were among the dozens mounting their support.

Lewis and his longtime friend on the other side of the aisle, retiring U.S. Sen. Johnny Isakson made national headlines with an emotional embrace during Isakson’s retirement speeches. Isakson — who retired from service after his own battle with Parkinson’s — shared his prayers for Lewis.

“They don’t make them stronger or braver,” Isakson tweeted, “and I’m confident (Lewis) will take on this challenge as he has every other he’s faced: with courage and determination fueled by his strong faith.”