WASHINGTON — Representative Jamie Raskin, Democrat of Maryland, announced on Wednesday that he had been diagnosed with a “serious but curable” form of cancer.
Mr. Raskin, 60, who is a member of the House Jan. 6 committee and was recently chosen to become the top Democrat on the Oversight Committee, said he had diffuse large B-cell lymphoma and would soon begin a course of outpatient chemo-immunotherapy.
“I expect to be able to work through this period but have been cautioned by my doctors to reduce unnecessary exposure to avoid Covid-19, the flu and other viruses,” Mr. Raskin said in a statement. “In addition to destroying cancer cells, chemotherapy impairs natural antibodies and undermines the body’s immune system. I am advised that it also causes hair loss and weight gain (although I am still holding out hope for the kind that causes hair gain and weight loss).”
Mr. Raskin said he plans to “get through this and, in the meantime, to keep making progress every day in Congress for American democracy.”
Few members of Congress have been as aggressive in trying to hold former President Donald J. Trump accountable for the Jan. 6, 2021, attack on the Capitol as Mr. Raskin, a former constitutional law professor at American University and Maryland state senator.
Mr. Raskin is known on Capitol Hill for his detailed discussions of U.S. history and the nuances of the Constitution. He is the chief sponsor of legislation to create a commission that could remove a president from office under the 25th Amendment.
A Harvard Law graduate, he has also released a memoir, “Unthinkable: Trauma, Truth, and the Trials of American Democracy,” about 45 days that changed his life around the time of the Capitol siege and the death of his son.
Mr. Raskin was the lead impeachment manager in Mr. Trump’s second impeachment trial, during which seven Republican senators joined every Democrat in voting to convict the former president of incitement of insurrection for his role in the attack on the Capitol. Though that vote fell short of the 67 senators needed to convict, Mr. Raskin has frequently noted that “commanding majorities” in both the House and the Senate believed Mr. Trump was guilty.
Days before the riot, his son, Tommy, 25 and a student at Harvard Law, died from suicide on New Year’s Eve. Debilitated by grief, Mr. Raskin then lived through the assault on the Capitol. He almost immediately began pressing to impeach Mr. Trump for inciting the violence, and within days, Speaker Nancy Pelosi appointed him to lead the effort.
In that moment, Mr. Raskin has said, the assignment gave him a sense of purpose.
As soon as Mr. Raskin announced the diagnosis, well-wishes began to pour in from his colleagues on Capitol Hill.
“Jamie Raskin is a national treasure — an oasis of legal integrity and intellect at a time when both are desperately needed in democracy’s defense,” Representative Ritchie Torres, Democrat of New York, wrote on Twitter. “I am praying for his strong and swift recovery as he undergoes cancer treatment. America needs you, Jamie.”
“Wishing a fast recovery for an outstanding public servant and a long-time friend,” wrote Ron Klain, the White House chief of staff.