A woman had a 5cm brain tumour - but her GP told her 10 times that she merely had a virus and needed vitamins.
It was only when the woman's husband paid £700 for private treatment that the truth was finally discovered – and her life was saved.
Sheela Gandhi, 57, had become increasingly unsteady on her feet but her GP continued to insist there was nothing seriously wrong with her.
Her worried husband Bharat, 60, shelled out for an MRI scan which found a 5 cm tumour at the base of Sheela's skull.
She had a six-and-half hour operation on December 23 at St George's hospital in Tooting, south London, and spent four days over Christmas in intensive care. She was discharged on New Year's Eve.
Sheela, from Selhurst, told the Evening Standard: "It's because of my husband that my life is saved. He was fighting the authorities. I was crying in desperation but that made him persevere.
"That is the most frightening thing for me - doctors are qualified and they expect you to accept what they say."
She was taken to Croydon Hospital and then transferred to St George's, a regional centre of excellence for neurological conditions, after being found semi-conscious on her bedroom floor.
Bharat, said: "My wife and I had 10 appointments with our GP and were told each time it was nothing to worry about and sent home. I know my wife, and she just wasn't right in herself."
The tumour had been slowly putting pressure on her brain stem and could have killed her at any time.
Senior consultant neurosurgeon Henry Marsh, who led the St George's team, said: "The tumour was benign and, as surgeons say, 'co-operated', so we expect Mrs Gandhi to make a full recovery."
St George's deals with between 450 and 500 brain tumours a year. Bharat said: "If you aren't happy with the advice of a medical professional then don't be afraid to get a second opinion. I'm not interested in blaming people. Everyone makes mistakes. I am just glad that my wife is back home where she belongs."
The Gandhis are planning to set up a charitable trust to help raise awareness and support for people with neurological illnesses.
Their GP was unavailable for comment.