Clinical improvement of patients with emphysema after radiotherapy.

In advanced emphysema the reduced lung retractive force permits dynamic compression of the airways during expiration; this gives rise to breathlessness which is often refractory to conventional remedies. Radiotherapy causes shrinkage of lung tissue and has therefore been given as treatment to 10 patients with emphysema. They have been followed for two years, during which time three have died from various causes, but no adverse effect of radiotherapy has been observed. All the patients at some time experienced a reduction in breathlessness on exertion and an increase in the range of their daily activities; the distensibility of their lungs was on average reduced but the response to test exercise was not altered. The possibility that the clinical improvement may have been a placebo effect is now being investigated.