NSW Deputy Premier Prue Car says she is taking personal leave for "an undetermined period of time" after being diagnosed with breast cancer.

Ms Car, who is also the state's education minister and minister for Western Sydney, said she had informed NSW Premier Chris Minns over the weekend.

The member for Londonderry in north-western Sydney previously took time away from politics in 2022 after being diagnosed with kidney cancer.


Ms Car on Tuesday said testing had confirmed the breast cancer was unrelated to her previous diagnosis.

"Thankfully, because the cancer was caught early, my doctors are optimistic about my recovery — and so am I," she said in a statement.

"I've faced this challenge before, and I'm determined to beat it again.

"I'm going to have to receive some pretty significant treatment," she said in a video on her social media, noting the "prognosis is good".

"The amazing medical team around me are really hopeful about the prospects after treatment."


Ms Car said Courtney Housso would act as education minister and minister for Western Sydney in her absence.

"I look forward to returning to the role I've cherished since our government took office in March 2023 — a role I absolutely love," Ms Car said.

Ms Car noted breast cancer screenings were vital for early detection and treatment and encouraged all women to stay up to date with their checks.


Mr Minns said the thoughts of the government were with Ms Car.

"I know Prue well. She is a fighter, and I know she will face this challenge with the same determination and grace that she brings to everything she does," he said in a statement.

"I fully support her decision to take the time she needs to focus on her health and recovery, and I know she will be supported by expert care and the love of her family, friends, and colleagues."

Mr Minns confirmed that Ms Car would remain the state's deputy premier.

Written by David Hirst, ABC News.