'Breakthrough" is the most over-used word in the medical lexicon. A former editor of the 'British Medical Journal', the shibboleth-shaking Richard Smith, once challenged newspaper reporters to look back a decade or two and see how many of the discoveries reported as breakthroughs at the time had proved their worth since. Precious few, it is safe to say.
Last week was different. "Claudia's trachea", as it is already known, looks like being one of those landmarks that genuinely signal a scientific leap forward. The transplant of the world's first windpipe grown using stem cells taken from the patient, a 30-year-old mother of two from Barcelona, is without doubt an extraordinary achievement.
The press conference called to announce the breakthrough was free of the razzmatazz that sometimes surrounds these events. It was held in the offices of the estimable but tiny Science Media Centre, with half a dozen scientists from the international team squashed behind a table and perhaps two dozen journalists sitting almost in their laps in front.
It started with a video of the patient, a beaming Claudia Castillo, paying a fulsome tribute to the leader of the team, Spanish surgeon Paolo Macchiarini, and ended with a few hacks making a feeble attempt at applause. Behind the table, the researchers turned to each other and shook hands, a trifle self-consciously, in the best traditions of British team spirit.
The operation is to be celebrated on at least three counts. First it has transformed the life of Castillo from a wheezing invalid, whose lungs had been damaged by severe tuberculosis, to a fit young woman who can dance the night away.
Second, it has demonstrated what stem cell technology, which has promised much but so far delivered little, really can do. A donor trachea was stripped of its living cells and new cartilage grown from Castillo's own stem cells from her bone marrow. By "customising" the trachea in this way, scientists succeeded in making the transplanted organ indistinguishable from her own body to her immune system, avoiding the need for immunosuppressant drugs.
Third, it is a remarkable example of international co-operation, involving four research teams in three countries (Spain, Italy and the UK), marred only by the lack of co-operation shown by EasyJet, when the airline refused to carry the stem cells prepared in Bristol to Spain (a private jet was chartered instead).
Whether it can properly be described as a breakthrough will not become clear for another five or 10 years. But from where we are now it looks like one of the few scientific advances that deserve the title.
More Down's syndrome babies are being born, it was reported this week, signalling a growing acceptance of the birth defect by parents who are choosing to continue with their pregnancies rather than terminate them. That is clearly admirable. But why do we only hear from the parents of affected babies, and not from the parents of Down's syndrome adults? I wonder if they have a different tale to tell.