Former Republican Sen. Ben Sasse, who became known for breaking party ranks to criticize President Donald Trump and voted to convict him during his second impeachment trial, shared on Tuesday that he has been diagnosed with Stage 4 pancreatic cancer.

“This is a tough note to write, but since a bunch of you have started to suspect something, I’ll cut to the chase: Last week I was diagnosed with metastasized, stage-four pancreatic cancer, and am gonna die,” Sasse said in a post on X.

“I’ll have more to say,” he continued. “I’m not going down without a fight.”

Pancreatic cancer, while not common, is the third deadliest cancer, according to the National Cancer Institute. Oftentimes, the cancer is only identified after it has already spread to other parts of the body.

Sasse, who represented Nebraska in the Senate from 2015 to 2023, said he was “blessed” to be surrounded by loving friends and family members during this time. He invoked his Christian faith and quoted Scripture in his post.

The 53-year-old was one of only seven Republican senators who broke from their party and voted to convict Trump in his impeachment trial in the aftermath of the Jan. 6, 2021, attack on the U.S. Capitol. Sasse publicly criticized Trump while in office, including over his response to the COVID-19 pandemic and his treatment of women. Sasse once accused the President of “kiss[ing] dictators’ butts.” Sasse also lamented the direction the Republican Party was heading in.

“The violence that Americans witnessed—and that might recur in the coming days—is not a protest gone awry or the work of ‘a few bad apples.’ It is the blossoming of a rotten seed that took root in the Republican Party some time ago and has been nourished by treachery, poor political judgment, and cowardice,” he wrote in a piece for The Atlantic a little more than a week after the 2021 attack on the Capitol. “When Trump leaves office, my party faces a choice: We can dedicate ourselves to defending the Constitution and perpetuating our best American institutions and traditions, or we can be a party of conspiracy theories, cable-news fantasies, and the ruin that comes with them.”

In 2023, Sasse resigned from office to accept the role of president of the University of Florida. In his farewell address, he called his time in the Senate “a unique honor.” He also criticized extremism on both sides of the political aisle. “The Senate has a special role to play in America’s recovery,” he said, acknowledging that “this institution doesn’t work very well right now.”

He stepped down from his post at the University of Florida in 2024 to spend more time with his family, after his wife, Melissa, was diagnosed with epilepsy.

The couple has three children together, who Sasse mentioned in his post on Tuesday. His daughter Corrie was commissioned to the Air Force several months ago, and his daughter Alex graduated college last week, a semester early, he said. His teenaged son, Breck, started learning how to drive this past summer.

“I’ve got less time than I’d prefer,” Sasse said. “This is hard for someone wired to work and build, but harder still as a husband and a dad. I can’t begin to describe how great my people are.”

“There’s not a good time to tell your peeps you’re now marching to the beat of a faster drummer—but the season of advent isn’t the worst,” he continued. “As a Christian, the weeks running up to Christmas are a time to orient our hearts toward the hope of what’s to come.”