BOSTON (CBS) - Brendan Beauregard has never been a long distance runner, but that isn't holding him back from running the Boston Marathon in honor of his older brother.
"He's trying to fight for his life, trying to live on so it's what I want to do and I just think about that whenever I hit a tough mile or a tough hill,"said Beauregard, a student at Emerson College.
In September 2017, Patrick Beauregard, a corporal in the Marines and a newlywed, received a devastating diagnosis.
"I had severe stomach pains and that was it just out of nowhere. It wasn't improving so the next day I went into the ER. They were almost a split-second away from sending me home. They finally decided to run a CT scan of my abdomen and that's when they saw the tumor," Patrick told WBZ-TV.
Doctors told the 29-year-old he had stage four colon cancer. It had spread to his lungs.
"Complete shock. Utter disbelief," said Patrick Beauregard. "You're going through life, you're young, you're healthy. You think, no way. There's no way."
Patrick isn't the only one perplexed by his diagnosis.
"He was really the picture of health, yet he was diagnosed with stage four disease and the reasons underlying that are unknown," said Dr. Kimmie Ng, the director of the Young-Onset Colorectal Cancer Center at Dana-Farber.
What doctors do know is that there has been an alarming increase in the number of young adults diagnosed with colorectal cancer.
"Such that by the year 2030 it appears there will be double the rates of colon cancer in these young people and quadruple the rates of rectal cancer," said Dr. Ng.
Patients like Patrick are the reason why Dr. Ng founded the Young-Onset center. It launched in March, in conjunction with Colorectal Cancer Awareness Month, becoming one of the first of its kind in the country.
"We are one of the first to come up with a center that is devoted specifically to caring for these young patients under the age of 50 with colorectal cancer as well as to produce a concerted research effort around studying why this is happening," said Dr. Ng.
"The most frustrating thing is not knowing what caused this," said Patrick. "I'm glad they're doing all this research now and hopefully they find out the reason or reasons why there is such an uptick."
Patrick has been through 33 rounds of chemotherapy at Dana-Farber. Next month he will start a clinical trial. Despite all the hardships and uncertainty, he's still working, staying positive, and on a mission to increase awareness among young adults and medical professionals.
"The doctors and physicians, they also thought there's no way I had cancer so I'm glad that now that there's more awareness and I hope we break that stigma." said Patrick.
Exactly one year after his diagnosis, the Beauregard brothers ran a 5K together to help raise awareness. That's when Brendan decided to take their cause a step further by running the Boston Marathon for the Cam Neely Foundation, which provides support for cancer patients and their families.
But, more than anything, Brendan hopes to make his brother proud.
"He's always been my hero and my best friend in life," said Brendan.
If you'd like to contribute, visit Brendan Beauregard's Boston Marathon fundraising site.
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