Targeted thermal vapour ablation of severely emphysematous lung tissue improves lung function and quality of life with an acceptable safety profile, the joint Australian-European STEP-UP study has concluded.
The study recruited 70 patients with severe, upper lobe-prominent emphysema, an FEV1 of 20-45%, substantial hyperinflation and a 6 minute walk test of >140 metres.
They were randomised 2:1 to ablation using thermal water vapour, delivered bronchoscopically to one or two segments at baseline and 3 months later, or to standard medical management.
At 6 months FEV1 had improved by 14.7% and St George’s Respiratory Questionnaire Scores had improved by 9.7 points in the ablation group (changes of 12% and 8 points, respectively, are considered clinically meaningful).
Professor Greg Snell, from the Alfred Hospital in Melbourne, contributed to STEP-UP.
“Although the trial had specific, tight selection criteria, the findings would apply to many Australian emphysema patients with patterns of disease not easily treated by any other means,” he told the limbic.
“In addition, it may be possible to repeat treatments, but further trials will help clarify this.
“It’s reasonable to imagine more widespread use of such technology with the aim of improving quality of life and eventually – we hope – length of life.”
Although the procedure is theoretically available in Australia, it is not yet funded by Medicare, he said.
The Prince Charles Hospital in Brisbane and Sir Charles Gairdner Hospital in Perth also participated.
While lung reduction surgery and bronchoscopic strategies including valves and coils can help relieve emphysema, they have to be applied to an entire lobe even though they may contain segments of relatively healthy tissue.
“Ideally, these healthier segments should be preserved and allowed to expand after treatment to positively affect lung function, improve lung efficiency, and preserve as much lung parenchyma as possible,” the study team wrote in Lancet Respiratory Medicine.
Segments were selected for treatment on the basis of volume and disease state as defined by tissue-to-air ratio – a measure of lung density.
The procedure had significant side effects, increasing the 6-month rate of serious adverse respiratory events to 36% compared to 13% in the control group. COPD exacerbations and pneumonia were most common. One treated patient died from a COPD exacerbation that was deemed as possibly related to treatment.
An editorial commented that, as with any innovation, big challenges remain. They include identifying the likely best responders, defining the long-term safety profile, and further improving the current safety profile.