The actress starred as hairdresser Julie Cooper in the soap, and also had a glittering career on the West End stage.
Her death was confirmed on a Facebook page that was set up to help raise funds for the actress’s treatment.
It read: “Dear wonderful supporters of Louise.
“I am so sorry to have to let you know that an hour ago we lost Louise to that horrid disease. All of her family were with her.
“The world has lost a truly special person, prodigiously talented, and a friend to all.
“Can I thank all of you who joined us in this battle and who helped Louise to have hope.”
Dear wonderful supporters of Louise. I am so sorry to have to let you know that an hour ago we lost Louise to that...Posted by Fundraising for Louise Plowright's life saving treatment on Tuesday, 1 March 2016
On stage, Louise recently starred as Madame Morrible in ‘Wicked’, and left when she was forced to withdraw from the production due to her diagnosis.
She made her debut in ‘Mamma Mia!’ back in 1999.
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