Alveolar macrophages activity in patients with lung cancer

In order to evaluate alveolar macrophages (AMs) phagocytosis frequency (PHF), phagocytosis index (PHI) and intracellular killing in patients (pts) with lung cancer compared to normal subjects, we recovered AMs by bronchoalveolar lavage (BAL) during diagnostic fiberoptic bronchoscopy (FBS) of 25 pts with lung cancer (5 undifferentiated large cell, 11 squamous cell carcinoma, 9 small cell lung cancer) and of 8 healthy volunteers. In the pts with lung cancer the phagocytic activity was lower than normal, with no correlation with tumor histology or BAL site. Only PHF and PHI were statistically lower than in normal subjects. In cases of limphonodal or metastatic diffusion, the inhibition of AMs activity was more significant than that observed in limited cancer. It is possible to suppose that the depression of AMs activity could lead to a quicker local and diffused tumor growth.