Socialite Tara Palmer-Tomkinson has been found dead aged 45.
The former Sunday Times columnist, reality TV star, and goddaughter of Prince Charles had received treatment in 2016 for a non-malignant brain tumour.
Officers were called to her flat in Bramham Gardens, South Kensington, at 13:40 GMT. A woman in her 40s was found dead at the scene, the Met Police said.
The death is being treated as unexplained.
Palmer-Tomkinson rose to fame in the 1990s as a hard-partying “it girl”, putting her names to several columns chronicling her glamorous lifestyle.
She was diagnosed with the tumour last January after returning from a skiing trip, and hit back at critics who blamed her frail health on her well-documented cocaine addiction.
She was a close friend of Prince Charles, and attended the wedding of the Duke and Duchess of Cambridge in 2011.
The Prince of Wales and the Duchess of Cornwall led tributes to Palmer-Tomkinson, and said they were “deeply saddened”, by her death.
Former Daily Mirror editor and US TV host Piers Morgan paid tribute in a tweet that read: “RIP Tara Palmer Tomkinson, 45. A fun, feisty woman who battled many demons. Very sad news.”
Later in her career she appeared on reality TV series I’m A Celebrity… Get Me Out Of Here! in 2002, as well as several other TV shows.
Her father Charles was a former Olympic skier who taught Prince Charles.
The family was skiing with the Prince in the Alps in 1988 when they were hit by an avalanche that killed one member of their party, Major Hugh Lindsay, and left Palmer Tomkinson’s mother Patti with serious leg injuries.