'Dance Moms' ' Abby Lee Miller Reveals She's Starting Round 3 of Chemotherapy

"I start round 3 of chemo......... another battle that I must win!!" Abby Lee Miller posted on Instagram

Abby Lee Miller is staying positive as she prepares to begin her third round of chemotherapy.

The former Dance Moms star revealed in an Instagram post Friday that she will undergo another round of the intensive cancer treatment.

“Happy Friday!!! I should be planning a weekend of fun in the sun at the pool! ☀There’s nothing I enjoy more than swimming and a good tan!” she captioned a photo of herself smiling, standing by a pool.

“Instead, I start round 3 of chemo……… another battle that I must win!!! #aldc #aldcla #abbylee #dancemoms,” she shared.

In April, one day after undergoing emergency surgery for what was initially thought to be a spinal infection, the 51-year-old — newly released from prison — was preliminarily diagnosed with non-Hodgkin’s lymphoma, a cancer that develops in the lymphatic system.

“It was not an infection, it was a type of a non-Hodgkin’s lymphoma – it’s a type of a cancer,” said Dr. Hooman M. Melamed, an orthopedic spine surgeon at Cedar Sinai Marina Del Rey Hospital who has been treating the star. “We’re getting an oncologist involved and we have to figure out what the next steps are as far as chemotherapy or radiation or more spine surgery. Depending on the tumor type, depending on the sensitivity of the tumor – it just depends the type but I feel more than yes, she will undergo chemotherapy or radiation.”

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The doctor added that it is a “preliminary diagnosis pending pathology and oncology results.”

Last week, a source told PEOPLE that Miller was struggling amid her cancer diagnosis.

“She has two more chemo sessions to go, but she’s in a really bad place — mentally and emotionally,” said the source. “She’s really losing it.”