Tarek El Moussa likely expected fan feedback as a star of the HGTV reality series "Flip or Flop," but he never could have predicted one of its 4 million viewers would make a potentially life-saving recommendation.

During a 2013 marathon of the TV show — which chronicles the renovation and attempted sales of houses secured by Tarek and his wife, fellow real-estate agent Christina — registered nurse Ryan Reade spotted a lump on Tarek's neck and contacted the show's producers to suggest he get it checked out.

"I noticed that at certain angles, at certain times, it just caught my eye that Tarek had a lump on his throat," Reade told TODAY, "and I thought it was something that needed to be brought to his attention."

It did. Joining Christina in thanking Reade, Tarek called Reade's notification a "lightbulb moment," as he'd been having throat problems for three years. A heavy smoker, Tarek had dismissed the lump as just a fatty mass, and so had his doctors prior to Reade's note.

"We seriously looked at each other and we're like, 'OK, it's not something might be wrong; something is wrong,'" Tarek said.

Biopsy results revealed the lump and smoker's cough were symptoms of Stage-2 thyroid cancer.

"[The] interesting thing about thyroid cancer is it most often shows up as just a lump in the neck," Dr. Michael Yeh, a UCLA associate professor of surgery, told TODAY. "Oftentimes, blood work will be normal; the patient will feel fine. The average person, by the time we get to them, probably had the cancer for a couple years."

Although Tarek said he told his wife "we're going to beat this thing," Christina recalled being fearful, especially since they'd just had a baby, Taylor.

"I was just feeling totally overwhelmed about losing him, him having to go through treatments, our daughter," Christina said.

Within a month of the biopsy, Tarek had his thyroid and lymph nodes removed and began iodine radiation treatment, sapping his energy and resulting in migraines, but he and Christina continued to work.

"We made a decision not to slow down, not to stop," he said. "We're gonna run the business. We're gonna fight through this cancer, 'cause the second you slow down is the second it gets scary and you start getting depressed."

For the past year and a half, Tarek has been in remission. He and Christina are basking in parenthood, bonding with Taylor, who celebrated her fifth birthday this year, and — after two failed in-vitro attempts — raising Brayden, who turned 3 months old last week.

Welcoming Brayden to the world was "a turning point in our life," Tarek said. Although they've continued to host "Flip or Flop," whose new season premieres Dec. 3, Tarek has since scaled back on work days that often spanned 14 hours.

Christina has noticed the change. "After we found about cancer, him and my daughter got closer than they've ever been," she said.

Added Tarek, "It's like the best thing in the world."

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