Cancer patients are having to wait for crucial treatment because the machines which administer it keep breaking down.

Marina Stuart, 50, visits the Royal Sussex County Hospital in Brighton every day to receive radiotherapy for throat cancer.

She travels from her home in Eastbourne to use the hospital's linear accelerator radiotherapy machines, which cost £1 million each.

The treatment should only take a few minutes but her husband Andrew says teething problems with the machines are making patients' lives a misery, despite hospital staff putting in extra hours to try to make up the time.

Mr Stuart, of Seaford Road, said: "For the last two weeks one machine or the other has been breaking down.

"It's extremely stressful for people who are already stressed because they have cancer.

"My wife has been in a terrible state and to arrive at the hospital and be told the machines are not working is awful. These delays have been affecting dozens of patients."

Some patients have waited hours for treatment after arriving at the hospital for their appointments.

On one occasion, patients were told not to come for treatment at all until the machines were fixed.

Linear accelerators target high-energy photon beams at tumours. The machines can match their beams to the shape of the tumour to provide a more precise and efficient treatment.

Mr Stuart praised hospital staff, who he described as "brilliant", but said the constant breakdowns were affecting patients' health.

The first high-tech linear accelerator machine arrived at the hospital in May and the second last month.

A Brighton and Sussex University Hospitals NHS Trust spokeswoman said the machines had broken down at the same time by coincidence and the faults were not related.

She apologised to patients for any distress caused and said both machines were now working and the hospital was due to get a third machine in June 2004.