Patrick Dempsey Says His Mom's Cancer 'Really Woke Me Up to the Impact' the Illness Can Have on a Family (Exclusive)

Patrick Dempsey says his eyes were opened when his mom was diagnosed with cancer.

In an exclusive conversation with PEOPLE, the actor, 58, speaks candidly about his mom Amanda Dempsey's cancer diagnosis and how it impacted his entire family.

"My mother was diagnosed with ovarian cancer in the late nineties, and she had over 12 re-occurrences over 17 years, and passed away in 2014," he says. "So that really woke me up to the impact it has on a family."

Noting that he "felt helpless" and "wanted to be able to contribute in some way," the Grey's Anatomy alum later founded the Dempsey Center, a nonprofit that provides personalized and comprehensive cancer care at no cost. He is currently working with Pfizer and the American Cancer Society’s Change the Odds initiative to shine a light on resources and support available to those affected by cancer.

"I think people need the support," Dempsey says. "There needs to be a sense of community, and we need to be able to talk about this openly without any shame, and to be loving and supportive to people that we come in contact with who have a cancer diagnosis — and also the family. The whole family is impacted, and they need to be understood, and they need to be cared for as well."

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The Change the Odds initiative specifically focuses on underserved communities across the United States — something very familiar to Dempsey.

"I grew up in a small town in Maine, a rural community, and this really spoke to me," he explains. "It's like, how can we get the messaging out there to encourage people to get screened, [despite] the barriers that come up."

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"Especially in the remote areas, it's almost like a medical desert," Dempsey continues. "You can drive two, three hours to get to a hospital. ... That's a very long period of time. The irony is that you're called a patient because you have to be patient."

The star adds, "So I think it's all part of our plan. We work from prevention into survivorship and everything in between, while also supporting caregivers and children... And with the American Cancer Society, they have rides, so if you can't get yourself to a hospital or a clinic, there are opportunities there. If you need a place to stay, there's a place to stay. There's so much information on their website that can be helpful and remove those barriers."

For Dempsey, he practices what he preaches and takes his own health seriously — which is something he also implores others to do.

"The numbers are just staggering that one in three women will have a diagnosis in their lifetime and one in two men will. You can have a long life if you get the screening done," he says. "I had one of mine done this week, and I have one coming up in a month."

PEOPLE's Sexiest Man Alive for 2023 also highlights the importance of being your best advocate when it comes to overall health.

"Listen to yourself. I think people need to listen to their body. They know what is right for them," Dempsey explains. "Keep asking the questions and listen to yourself, and then find out what's best for you — you're your own best advocate."

"You understand your body, you have instincts, so you got to listen to that voice and see where that takes you," adds the Dexter: Original Sin star.