CoppaFeel! Founder Kris Hallenga passed away at the age of 38 after being diagnosed with breast cancer at the age of 23.
The Cornish campaigner was first diagnosed with incurable secondary breast cancer in 2009 and given a life expectancy of just two years.
Instead of succumbing to despair, Kris made a conscious decision to face her illness head-on, determined to seize every opportunity and live life to the fullest.
In a statement about X, CoppaFeel! said: 'We share the sad news that our founder, boob chief, colleague, friend and queen of sparkly turds, Kris, has passed away.
'Kris approached life in a creative, fun and fearless way and showed us that it is possible to live life to the fullest cancer.'
CoppaFeel! Founder Kris Hallenga (photo), who had stage four breast cancer, has died at the age of 38
The campaigner was first diagnosed with incurable secondary breast cancer in 2009 and was given a life expectancy of just two years
Kris has consciously chosen to face her illness head-on and seize every opportunity
Kris is the bestselling author of Glittering A Turd, seen here with an advertisement for her book detailing how she discovered her life after being told she was going to die
Kris and her twin sister Maren took their charity CoppaFeel! to great heights, including creating monitoring tools, projecting onto the Houses of Parliament and displaying the first nipple on a billboard.
The charity has a huge following on social media and encourages women to check their breasts for signs of cancer.
Kris is the bestselling author of Glittering A Turd, a book about how she discovered her life after being told she was going to die.
This is a breaking news story. More to follow.