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Lori Allen -- star of TLC's reality show Say Yes to the Dress: Atlanta -- has revealed she's battling breast cancer. 

The cancer diagnosis is revealed in a clip featured on People.com for the upcoming TLC special Say yes to the Cure: Lori's Fight, set to air October 26.

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"I went in for a regular mammogram, and the results came back positive, and I have breast cancer," Allen tells shocked employees at her business Bridals by Lori. "I've got to have surgery and I'm going to be out for quite a while."

In the one-hour special, Allen will open up about her "devastating" cancer diagnosis in April and chronicle her struggle to beat the disease. "Wanting to turn something very negative into something positive, I decided to share my journey -- in hopes that I can raise breast cancer awareness and perhaps help other women facing breast cancer be less afraid," she explained.  

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