The reality star passed away at her home in Oregon on Tuesday night, the rep told Access.
Lyon was diagnosed with stage three breast cancer after exiting "Survivor" in 2005, where she finished fourth in the reality contest. She underwent a bilateral mastectomy and underwent chemotherapy, according to People. And she once credited "Survivor" for helping her battle the disease.
"'Survivor' taught me there's an end in sight," she previously told the mag. "As hard as it is, it will be over, and you have to appreciate every day."
"Jen was a genuinely selfless, sweet-natured person," he said on Wednesday, after news broke of her death. "She always had a smile. She cared about every person."
Lyon, who was born in Nevada, but grew up in Washington and Oregon, had become an advocate for breast cancer research.
"This has really rocked the 'Survivor' community. It's just so sad," Carty added.
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