Great treatment for some. But for those who ask questions it's a different story

The Interbalkan European Medical Centre rises from the out-of-town shopping area like a marble-clad spaceship. Imposing flights of stairs to the entrance are flanked by granite-stepped waterfalls, while stainless-steel walkways add to the feeling that one is entering a futuristic bubble rather than checking into a hospital.

A circular atrium soars upwards, with white marble gleaming out at you from floors and walls on all sides. Glass elevators glide up and down the spine of the building while doctors and nurses stride purposefully around, passing awed visitors who creep quietly about their business as though at church.

On the fourth floor of this hospital in the northern Greek town of Thessaloniki, in room 420, John McCumisky, a 69-year-old retired textile worker from Stockport, is recovering from a full knee replacement operation. For Mr McCumisky or any other British patient sent to a private hospital abroad, the concern must be: who is looking after you?

We were looked after all too closely by the hospital's imposing security guards, who apprehended us as we tried to leave the Interbalkan, having, with his express permission, interviewed and photographed Mr McCumisky.

The security men, in dark-grey suits, escorted us back into the building, guided us to a lift and took us down two levels into the bowels of the hospital. They told us police had been summoned – although they never showed up – and the photographer with me, Nikos Pantis, was ordered to hand over his film.

Eventually we were "released" as it dawned upon the Interbalkan and Operations Abroad that what they had on their hands was potentially a public relations disaster. By the end of an exhausting day, I felt more like a British planespotter than a British journalist. The only difference was that the photographs in our camera were of a British patient recovering from an operation in a Greek hospital.

Mr McCumisky's experiences in the Interbalkan were, thankfully for him, more pleasant. "I feel as if I'm Captain Kirk. Everything here is so modern and sophisticated," he said as he surveyed the panoramic view of the Thermaic Gulf from his window.

He waited nine months for his operation on the NHS before, tired of waiting, he paid Operations Abroad £6,900 to arrange private surgery in Greece.

"They don't muck about here – as well as my knee I've had a full body check, heart, the lot. I've had about 10 doctors in to see me since I arrived," he said. "When I saw a specialist in Stockport you could tell I was the last patient of the day and they weren't interested in me. This is the first time I've felt I really got the doctor's attention."

Mr McCumisky's wife, Joan, said: "After all, wasn't the first doctor a Greek? I think his name was Hippocrates – he was the one with the oath."

The Interbalkan, built two years ago at a cost of £70m, is giving Mr McCumisky VIP treatment. The hospital is part of the Athens Medical Group, a business set up by the tycoon George Apostolopoulos. The idea behind the company, he said at its inception 15 years ago, is that "no Greek should seek medical care abroad". For years, wealthy Greeks have flown to London for private operations.

Mr Apostolopoulos has received high-level political backing in Athens, and the Greek embassy in London hosted the ceremony at which Operations Abroad secured exclusive rights to send NHS patients to the Interbalkan.

Mr McCumisky is being seen as a test case – proof positive that this Greek hospital could treat thousands of NHS patients in just the same way.

"Basically, his experience will be identical to that of the NHS patients," said Kenneth Taylor, the general manager of Operations Abroad. "They will undergo an operation, and then complete their rest and recuperation, in Greece." With five flights a week from Gatwick airport to the Greek city, a journey that takes about three hours, the distance was not a problem, he said. Medical experts, however, question whether it is wise to put patients either needing or recovering from orthopaedic operations, such as hip and knee replacements, on a cramped airplane for even short flights.

It's not the only obstacle the hospital must overcome. It must also persuade the Department of Health to send its patients there. A DoH spokeswoman confirmed that a meeting with Interbalkan representatives had taken place before Christmas, but insisted that initial pilot studies to send patients abroad, running up to the end of April, would be conducted only in northern France and Germany.

However, a spokesman for the south-coast health authorities taking part in the pilot scheme said: "We are not ruling out the possibility that we may use Thessaloniki. We have had lots of discussions with them."

The Interbalkan needs foreign patients to make Mr Apostolopoulos' huge investment pay off. Yesterday, Mr McCumisky was being feted. A plane load of journalists is being flown in this week to meet him, while the Greek press, amazed to find an Englishman seeking treatment in their country, is highly excited.

The planned media offensive goes some way to explaining why the hospital was less than keen for The Independent on Sunday to secure this first, exclusive interview with the British pensioner.

Additional reporting by Henrietta Roussoulis and Robert Mendick