She said she had breast cancer. Her family was devastated. Yet she had never even consulted a doctor. Liz Hunt reports on the little- known world of 'factitious disorders'
When Jenny told her family and friends that she had breast cancer and that doctors had said there was no hope, sympathy for the shy young woman knew no bounds. She impressed them all with her courage and her desire to carry on as normal for as long as she could.

Her work colleagues rallied around, offering to take on many of her duties. They ferried her back and forth from the office, and included her in social events whenever she felt up to it.

They were horrified by the ravages of the disease on the 35-year-old's body. Jenny's weight had plummeted by 20lb and her hair was falling out. Each morning her mother would cry over the handfuls of her daughter's hair she found in the sink. Make-up could not hide the dark circles under Jenny's eyes nor the gauntness of her cheeks. When she eventually became completely bald she took to wearing a wig.

Jenny told her friends that she drew particular strength from the breast cancer support group she attended at the hospital. She never missed a session, sharing her experiences with other women who had the disease. Schoolchildren raised money for Jenny's care, and the local newspaper in the small American town where she lived documented her bravery.

It was only two years later, when counsellors at the cancer support group tried to find out more about Jenny's condition, that the great deception that was Jenny's so-called illness was exposed. Doctors whom she claimed were treating her had never heard of her. Jenny had never been diagnosed with, or treated for, breast cancer.

There are few people who have not faked illness at some point in their lives, manufacturing a headache, stomach upset, or muscle strain to win sympathy. Some may be more devious, using their pretend illness to extricate themselves from a work or social commitment. But there is another group of "patients" who will play sick to pathological, sometimes fatal, extremes. They are factitious patients and, like Jenny, they will go to any lengths to convince an audience of their ill health, irrespective of the suffering it causes to their family and friends.

In their new book, Patient or Pretender, Inside the Strange World of Factitious Disorders (John Wiley) Drs Marc Feldman and Charles Ford explore the condition which, in its most severe form, manifests itself as Munchausen syndrome. Drawing on the first study into the disorder by America's National Institute for Allergy and Infectious Disease, involving approximately 350 people, the doctors' interest was triggered by the increasing number of factitious patients being referred to them, and by the public's interest in Munchausen syndrome.

But, according to Professor Ford of Alabama University School of Medicine, the two conditions are all too often confused by the medical profession. "With few exceptions in the past 30 years, the terms factitious disorder and Munchausen syndrome have been used interchangeably," he says, "but a distinction must be made between them." He describes a pyramid in which the benign use of faked illness is the base; factitious disorders are the middle, and chronic factitious disorders, or Munchausen's, form the pinnacle.

The study estimated that as many as 9 per cent of the population suffer from factitious disorders. Unlike Munchausen syndrome, factitious disorders are often one-offs that may be dropped as suddenly as the symptoms of the chosen illness are set in motion. What's more, if detected, patients often respond positively to psychotherapy. True factitious patients are those who consciously feign physical or psychological symptoms to assume the role of a patient because they desire attention, sympathy and caring. He or she is not a malingerer - someone seeking financial or other such gains from their illness. Unlike Munchausen's sufferers, they rarely injure themselves physically and, when they do, may step up to the next level - Munchausen's.

Although factitious disorders are generally non-pathological, the seriousness of the condition and its impact on family and colleagues, carers and health services is frequently underestimated. Jenny's mother and colleagues were victims of her condition, too, as were nursing staff at the hospital - whose time and attention were taken away from needier patients, insists Professor Ford. By the time patients are detected - and many of them are not - they will have undergone a battery of costly tests and exploratory operations.

So when Jenny was referred to Dr Feldman at the Center for Psychiatric Medicine in Birmingham, Alabama, the first thing he did was to check her work attendance, insurance and disability claims. He found that in two years she had taken little time off work, and was not receiving any benefits.

Dr Feldman discovered that the roots of Jenny's fantasy life as a cancer victim lay with her former fiance. After a year of living together, he had broken off their engagement with no warning, and asked her to leave his flat. She was devastated. Her life had been defined by her engagement to this man, and she felt worthless without it. Suffering from depression and having no one to turn to, she "became" a cancer patient, which provided her with an emotional outlet. She nurtured the belief that her fiance, once he knew, would rush back to her side.

Jenny applied herself to being the perfect cancer patient, modelling her appearance on that of a neighbour who really did have breast cancer. She dieted to achieve an emaciated look, she cut her hair and eventually shaved her head completely, to mimic the effects of chemotherapy. The responses of those around her were exactly what she needed: sympathy, caring, and admiration. Suddenly, Jenny mattered again.

Dr Feldman believes that Jenny may have found fulfilment as a permanent cancer patient for years but, once confronted, she swiftly admitted her deception and agreed she needed help. She responded well to anti-depressant drugs and intensive therapy and, following discharge, moved to a new town to begin life again.

Many factitious patients do well once they understand the motivation behind their illness, but some do not and if they use self-mutilation to generate convincing symptoms, the consequences can be fatal. A 26-year- old laboratory technician treated by Dr Feldman presented with a life- threatening low blood count. Tests were ordered to discover where she was bleeding internally - the most likely explanation - but they were all negative. Eventually, she admitted she was a "personal vampire". When stressed she said she would bleed herself, using syringes she stole from the lab, withdrawing blood in larger and larger amounts until she felt calmer. She discharged herself from the hospital and was never heard of again, Dr Feldman says. "She never returned to the clinic because we knew what she was up to. This woman could have died from what she was doing."

At the top of Professor Ford's pyramid of faked illnesses is Nina Stansfield, a 41-year-old woman from Blackpool. Diagnosed with Munchausen's syndrome in 1979, she has had 61 operations resulting from faked symptoms. On her 29th birthday she set herself alight so that she could be admitted to hospital. She has taken an overdose on 14 Christmas Eves to guarantee she would spend the holiday on a ward. Ms Stansfield, who features in a Channel 4 documentary next week, says she is addicted to hospitals because she associates them with the happiest days of her childhood, when nurses would look after her while her mother visited her dying father.

It is only since 1991 that Ms Stansfield has managed to wean herself off faking illness. Ironically, it is not therapy that has been her salvation but the plethora of television hospital soaps such as Casualty, A Country Practice, Chicago Hope, and ER. "I have two VCRs for when programmes clash," she says. "I'm usually taping one lot of hospital programmes while watching another. They are my substitute. I still wake up every morning wanting to go to hospital, but these programmes are keeping me out."

'Cutting Edge: Deception', will be broadcast on Channel 4 on Monday 23 October at 9pm.