Her legs and face are swollen, and with each slight movement she winces in pain. Lying on a hospital bed in the Ghanaian capital of Accra, there are moments when Ama Sumani appears incoherent. Then it all becomes too overwhelming and tears roll down her cheeks. 'I wish I was still in Cardiff,' she says quietly. 'Why could they not have kept me there? Why could they not have treated me and then sent me back?'

It's more than two weeks since Ama, a 39-year-old widowed mother of two, was taken in a wheelchair from a Cardiff hospital by three immigration officials, flown to Accra, then dumped in a city she had visited just once before in her life.

Suffering from malignant myeloma, for which she was receiving dialysis treatment at the University Hospital of Wales, it was a journey many condemned at the time as nothing short of a death sentence for a woman whose crime was to have overstayed her visa.

With no funds to cover the £50-a-day cost of dialysis in Accra, without which she would die, her future seemed bleak. Anonymous well-wishers have since contributed to the cost of her treatment, but just for three months.

And after that? She looks up, as the tears begin again. 'After that, I am in God's hands,' she replies.

Ama is terminally ill. The cancer has damaged her kidneys and she needs dialysis three times a week if she is to prolong her life. But, though aware her visa was out of date, she still finds it difficult to understand how she ended up here, in the treatment room at Korle-Bu Hospital, in a city she had spent just one day in - and that was on her way to the UK to pick up her visa in 2003.

'The doctors were trying to save me, but the people who made me leave are trying to kill me,' she tells The Observer. 'The doctors told me that if I was without treatment for two weeks, I would die. I said to the people who took me: "Why are you doing this? Why are you sending me to die?"

'How long will I live? What are my chances? I cannot say. I have no one here with me, to lead me through such questions, to speak to the doctors for me.'

Her bewilderment is all the more acute because she knows no one in this city. She comes from the north of Ghana, many hours away. Her family are there still and thus unable to help her, and no hospital there is equipped for dialysis. 'When I leave the hospital I cannot walk. I am so tired, so dizzy, my blood pressure is too high,' she says. 'I tried to make some soup, but I was too weak. I need to pay somebody to look after me, but I do not know people in Accra. I do not know who to trust. I just pray that someone will help me.'

Ama, who went to Britain on a student visa five years ago, appealed in vain against her removal. She first came to the UK as a visitor in 2003, then was granted a student visa. But her poor English prevented her from studying and she took paid work which contravened her visa. In 2005, she returned to Ghana to attend a memorial for her dead husband, but on re-entering the UK her student visa was revoked and she was given temporary admission. She became ill in 2006.

The fact that she was removed, rather than deported, means in theory that she can apply to return to the UK in future.

Campaigners in Wales are still fighting for her return. The decision to remove her was strongly criticised by church leaders and the medical profession. The Lancet called it 'an act of atrocious barbarism'.

When the immigration officers who had accompanied her on her flight returned to Britain, she was left alone. With no money, she checked out of the hotel where they had put her up for one night, taking with her the two suitcases and large plastic bag full of winter coats that she had brought with her.

'They put me in a hotel and paid for one night but it was so expensive. I needed help to find somewhere to stay. I needed to have treatment at this hospital. But they would not take me unless I paid. I had only enough for two days' treatment,' she says. 'And they wanted three months' treatment paid in advance.' With the recent donation Amu has been able to start the treatment. Each Monday, Thursday and Friday finds her trudging to the rundown hospital building and through the unit's entrance beneath a fading sign proclaiming 'Department of Medicine'.

Once that money runs out, her future is uncertain. But, as she faces it, she is thankful for what she has received from the British people. 'They helped me so much. All I can say is God bless them.'

The Border and Immigration Agency has said that though it feels 'personal sympathy' in her case, it is not enough to 'make it unique or to give this individual the right to a different process'.