Katie Couric on Colon Cancer After Chadwick Boseman's Death: 'Everyone Has to Be Vigilant'

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As people continue to grieve the shocking loss of actor Chadwick Boseman, who died at 43 after a private, four-year battle with colon cancer, others are sharing their personal experiences with the devastating disease and advocating for more public awareness.

Award-winning journalist and Stand Up To Cancer co-founder Katie Couric — who lost her husband Jay Monahan to colon cancer in 1998 — has been working tirelessly to raise awareness and funds for cancer research for more than two decades. She says she felt the loss all over again when she heard about the Black Panther star's passing.

"As soon as I saw the news, of course I thought about Jay because Chadwick was 43 and Jay was 42," Couric tells PEOPLE. "I imagined his family and him going through some of the same things that we went through, although his cancer was over a four-year period and for Jay, between the time he was diagnosed and the time he died, it was only nine months. Jay kept working, really until almost the very end, but I've been thinking about Chadwick's wife and his family and I've just been marveling over the fact that for four years he kept working."

Deborah Feingold/Corbis via Getty Katie Couric with husband Jay Monahan

Couric, 63, who also co-founded the National Colorectal Cancer Research Alliance and the Jay Monahan Center for Gastrointestinal Health, says that although the subject of diagnosing and treating colon cancer is sensitive and potentially uncomfortable, people must keep talking about it.

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"It's still fairly unusual for people under 50 to be diagnosed with colorectal cancer, but the number of young people who are being diagnosed with this disease is increasing while the number of people over 65 is decreasing," she says. "We have to keep talking about it because it's one of those things that's really easy not to talk about. It's not exactly something that you talk about at a cocktail party or at a PTA meeting, but it's so important because it's the second leading cancer killer of men and women combined."

She continues: "This is an opportunity to educate people about this disease. We are making some progress. The number of people who are getting screened or talking to their doctor has increased. I think there was a 20 percent increase in colon cancer screening after I talked about it publicly on The Today Show in 2000."

Robin Platzer/Twin Images/The LIFE Images Collection via Getty Katie Couric and Jay Monahan

Officially known as "the Katie Couric effect," she famously allowed The Today Show to broadcast her colonoscopy live on air in 2000, and has continued to encourage others to undergo the procedure. In 2018 she accompanied TV host Jimmy Kimmel to his first colonoscopy after he turned 50, and last year she shared photos from "his and hers" colonoscopies with her husband of four years, John Molner.

"It's highly preventable with the right screening," she says. "The thing about colon cancer, and some other cancers as well, but particularly colon cancer, is by the time you have really serious symptoms, it's often progressed, and that's why it's so critically important to be aware of the signs of colorectal cancer — especially if you're young. I think the polite way to say it is that if you notice a change in your bowel habits or in the appearance of your bowels and movements also, if you have rectal bleeding, it's something you can't ignore."

Couric, who has also partnered with PEOPLE to create SeeHer Story, a weekly digital video series produced to celebrate various female trailblazers from the past 100 years to today, encourages everyone to advocate for themselves, and to insist doctors take any symptoms seriously, especially for patients under 50. It's also crucial to know full family history, including other cancers that can increase one's risk for colon cancer.

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"Everyone has to be vigilant about this," she says. "You also have to really know your family history because if you have a family history of colon cancer, you need to be screened 10 years before that family member was diagnosed. So, my daughters (Ellie, 28, and Caroline, 24) will need to start being screened at 30 because Jay was diagnosed at 41."

"And by the way," she adds, "a lot of people don't have a family history. Jay didn't have a family history, he was the beginning of a family history. I think that a large percentage of people who are diagnosed with colorectal cancer don't have a family history. People also need to be aware of other cancers that were in their families, because that can increase your risk of colon cancer. If you have a history of breast or ovarian cancers in your family, you just need to really be vigilant."

Until there's a cure, Couric will continue advocating for more awareness and research funding.

"There haven't been enough research dollars dedicated to really studying different ethnic groups," she says. "We need to make the medical care more accessible for all people, which is something that clearly is being discussed and has been painfully revealed with the pandemic. People of color are two and a half times more likely to be diagnosed with COVID because of preexisting conditions or underlying health issues and what they call the social determinants of health, which are things like poverty and bad nutrition. And all the things that make people at greater risk for COVID may also make them a greater risk for colon cancer."

Her Stand Up To Cancer organization has prioritized those major issues.

"We have a whole colon cancer dream team. Our mantra is to collaborate instead of compete," Couric says. "So, we have scientists and physicians from a number of medical institutions and universities, and even biotech firms, all collaborating to try to figure out these questions and including why more and more young people are being diagnosed with this disease."

She continues: "We have to keep talking about it because it's easy to not take care of it or not talk to your doctor about it. And I think there's still an element of embarrassment, but I always say, don't die of embarrassment, right? We have to normalize these conversations. People have colons, and we can't feel squeamish about talking about something that has the potential to save people's lives."