A few weeks after revealing he had chronic myeloid leukemia, a type of cancer that affects the bone marrow but is treatable with oral medication, Boyle, the New Jersey Devils' 33-year-old center, and his wife, Lauren Bedford, were in Boston being warned by doctors that their 2-year-old son Declan might have Ewing sarcoma of the mandible, essentially a cancerous tumor in his jawbone.
"I couldn't put one foot in front of the other after that," Boyle said.
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Brian and Lauren spent three days waiting for a diagnosis on Declan, who had a gigantic, soft swollen chin and went for a CT scan at Hackensack University Medical Center in Hackensack, New Jersey, and an MRI at Boston Children's Hospital on back-to-back days.
"And to their disbelief, it wasn't what they thought it was," Boyle said. "We were bawling our eyes out that he didn't have cancer."
The diagnosis was an arteriovenous malformation of the jaw, a rare condition that impacts blood flow and oxygen circulation.
Declan, who turned 3 on May 19, has had numerous procedures done at Boston Children's Hospital to get the condition under control, but he still deals with pain, swelling and bleeding almost daily. Eating is a chore.
"It's getting better, but we're still chasing it," Boyle said. "It's tough. It's really stressful."
Boyle managed to finish with 23 points (13 goals, 10 assists) in 69 games this season, his first on a two-year contract with the Devils that he signed July 1, 2017. He helped New Jersey reach the Stanley Cup Playoffs for the first time in 2012.
He will be at the 2018 NHL Awards presented by Hulu at the Hard Rock Hotel & Casino in Las Vegas on Wednesday (8 p.m. ET; NBCSN, SN) as a finalist for the Bill Masterton Memorial Trophy, given to the player who best exemplifies the qualities of perseverance, sportsmanship and dedication to hockey.
Carolina Hurricanes center Jordan Staal and Florida Panthers goaltender Roberto Luongo are the other finalists.
Staal's daughter, Hannah, was delivered stillborn in February because of a terminal birth defect previously diagnosed by doctors. Luongo battled back from injuries to help the Panthers try to push for a playoff berth late in the season and, as a 12-year resident of Parkland, Florida, he was an emotional team spokesperson in the aftermath of the tragic shooting at Marjory Stoneman Douglas High School on Feb. 14.
Boyle missed the first 10 games of the season while he waited for his spleen to return to its normal size and for the medication he took to treat his CML, 600 milligrams daily of Tasigna, to begin working. He missed three more games in February because of an injury.
Boyle also missed multiple practices and morning skates traveling to and from Boston for Declan's appointments and procedures, but he represented the Devils at the 2018 Honda NHL All-Star Game in Tampa Bay as an injury replacement for teammate and Hart Trophy finalist Taylor Hall.
"I'm sure there were times he didn't feel as good as he looked, or he tried to hide how draining this whole process was," Devils goalie Cory Schneider said. "But you'd never know it because he always came to the rink with energy and tried to give it everything he had."
Boyle revealed in a conference call with reporters on Sept. 19, four days after training camp opened, that he had chronic myeloid leukemia.
Like with Declan, there were a few scary days in between finding out he had leukemia and being given an exact diagnosis. He said his thoughts in that time were with his wife and children, including daughter Bella, who turned 1 on May 24.
"Really, really, really scary," Boyle said. "And a little confusing because I didn't feel that bad."
But he knew he was going in the wrong direction because his fatigue was worsening, regardless of how much caffeine he plied himself with to stay awake.
"The day before camp, I got off the ice after a half an hour and had a 30-ounce cold brew from Starbucks," Boyle said. "I don't know if you've ever had a cold brew, but it's pretty good stuff. But I went home and I took a three-hour nap. I was worried at that point."
Boyle was diagnosed with CML shortly after. He said it was almost a relief because it could have been worse. Doctors warned him he could have a more acute form of leukemia, which would have been more invasive and required bone marrow transplants.
As soon as he announced his diagnosis publicly, Boyle experienced an outpouring of support.
Friends, current teammates and coaches, former teammates and coaches from his days with the Los Angeles Kings, New York Rangers, Tampa Bay Lightning and Toronto Maple Leafs, as well as media members and executives, all reached out.
"You hear cancer, you think the worst," Lightning defenseman Ryan McDonagh, who played four seasons with Boyle in New York.
Most everyone knew that Boyle's father, Arthur, had miraculously fought back and survived stage 4 kidney cancer.
"So to hear that it had happened to him was devastating," Lightning coach Jon Cooper said. "The guy has been affected by it, had given so much time to help battle the disease just to turn around and get punched in the gut by having it. That was really a tough one for us all to grasp."
Video: NJD@NSH: Boyle redirects Severson's shot home
McDonagh said he researched CML before reaching out to Boyle to get an idea of what he was up against.
"I remember just asking how it's going because you don't want to dig too deep," McDonagh said. "He quickly turns the question back to you and how you're feeling, how your family is doing. That just shows you the high character. He didn't want to spend a lot of time catching up on his situation, he wanted to find out about me. It was pretty surreal."
Boyle did that with a lot of people.
"I definitely felt better about it when I got off the phone than I did when I got on," Cooper said.
He explained the disease wouldn't force him to retire, that he would be back soon. He made his season debut Nov. 1 and scored his first goal in a home game against the Edmonton Oilers on Nov. 9. He scored his second against the Vancouver Canucks on Nov. 24, on the Devils' Hockey Fights Cancer night at Prudential Center.
"I just wanted to make sure I could reassure people, don't have that feeling. That's why I really wanted to get back on the ice as quick as I could, and I really wanted to play well when I did," Boyle said. "I'd rather be [getting guys angry] on the ice than have them feeling sorry for me."
The unknown part of Boyle's season was how much extra traveling he did back and forth to Boston.
Devils coach John Hynes and general manager Ray Shero worked with Boyle so he could miss a practice here or a morning skate there to be with his family. There were many days when he'd travel to New Jersey in the afternoon and play a game that night.
"What he did to be there for his family, managing it without really letting on to what he was going through, it was really impressive," Schneider said. "It felt like the hits kept coming for them. They handled it really well through the year and just did an amazing job of being a family and being there for each other."
Boyle credits his wife for keeping everything together. He calls her a superstar and says she's stronger than even he knew.
"She should win an award," Boyle said.
Instead, it's Boyle who might on Wednesday.
Talking with a friend last week, Boyle said he jokingly referred to the Masterton Trophy as what you win if terrible things happen to you. But he hopes his story is inspiring and brings awareness to cancer research and perspective on what many children and families deal with daily.
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Boyle's red and white blood cell levels are good, showing barely trace signs of CML left in him. He might be off his medication in three to six months, totally free to continue his career.
"I am in a good spot," Boyle said. "I'm certainly not concerned."
That's not the case with Declan, who has had two procedures in the past two months and just last week bit down hard on a piece of food that wasn't all that hard and started bleeding.
"Hopefully, we're toward the finish line of something that has been dominating our thoughts," Boyle said. "I get up and work out and I'm good. I can train really hard. But this is my kid. I wish it was me."