Sandra Lee experienced a medical complication recently, her rep told ABC News.
"There was a setback [on Tuesday night] due to what may be an infection post-mastectomy," a rep for Lee told ABC News. "But Sandra is her ever-fighting self."
Lee, 49, had kept her fans aware of her progress via Facebook and shared photos of herself at home with her partner, New York governor Andrew Cuomo.
On Aug. 3, she wrote that she visited the doctor and was using music to get "a boost of energy."
"Maintaining a positive attitude and surrounding myself with only good vibes is what helps me get through my appointments and helps me to continue to get stronger!" she added.