As a civil rights icon who marched for voting rights with Martin Luther King Jr. in 1965, Democratic U.S. Representative John Lewis of Georgia has faced adversity in many ways. But his next fight will have him facing off against metastatic pancreatic cancer, with which he was recently diagnosed, CNN reports.

“I have been in some kind of fight—for freedom, equality, basic human rights—for nearly my entire life,” said the 79-year-old, whose diagnosis came following a routine medical visit and several tests. “I have never faced quite a fight like the one I have now.”

Although Lewis says he is “clear-eyed” about his prognosis, “doctors have told me that recent medical advances have made this type of cancer treatable in many cases, that treatment options are no longer as debilitating as they once where and that I have a fighting chance.”

According to the American Cancer Society (ACS), the five-year relative survival rate for someone with Stage IV pancreatic cancer is 3%.

In the United States, pancreatic cancer is the third leading cause of death from cancer (7%), after lung and colorectal cancer cancers, according to the ACS. It is estimated that over 45,000 died from the disease last year.

A person with late-stage pancreatic cancer is commonly treated with chemotherapy and sometimes immunotherapy. New therapies, often combining chemotherapy with immunotherapy, as well as targeted treatments for those with specific mutations, have been shown to improve survival in some cases but often only by months, not years. Treatment for metastatic disease often focuses on keeping the cancer from spreading further and symptoms from getting worse.

As for Lewis, he plans to begin his weeks-long treatment plan soon. “I may miss a few votes during this period, but with God’s grace I will be back on the front lines soon.”

News of Lewis’s diagnosis hit the political community hard. Former Presidents Bill Clinton and Barack Obama as well as House Speaker Nancy Pelosi all sent prayers and well wishes to Lewis via Twitter. 

“I have decided to do what I know to do and what I have always done: I am going to fight it and keep fighting for the beloved community,” said Lewis, who is currently in his 17th term representing Georgia’s 5th Congressional District. “We still have many bridges to cross.”

For related coverage, read “Alex Trebek Reveals Stage 4 Pancreatic Cancer Diagnosis.”