Does pulmonary carcinoma affect the resonant properties of the thorax?

Intuition would suggest that any additional mass caused by carcinoma in the lungs should change the overall eigen system of the thorax in resonance. To confirm this the authors undertook measurements on several carcinoma patients to ascertain whether this is indeed the case. They present two cases in which one can observe this suspected behaviour without the problems of associated fluid or other conditions masking the effect one wishes to study. The authors have noted that usually only directly above the carcinoma site does any significant difference appear in the spectral response thus suggesting that carcinomas may generate an acoustical shadow. However, the authors conclude that further research is required before this can be used in any clinical sense.