Pathophysiology of Malignancy: I. Tissue Oxygen Tension of Benign and Malignant Tumors of the Skin.

Abstract

Tissue O2 tension of a variety of benign and malignant cutaneous tumors was measured in vivo by means of a platinum O2 cathode. Malignant tumors, and benign lesions characterized by marked cellular infiltration or acanthosis, showed a very low O2 tension as compared to that of the immediately adjacent normal skin. Benign lesions characterized by little or no increase in cellularity showed normal tissue pO2. The marked decrease of tissue O2 tension of malignant tumors is probably due to a combination of an abnormality of the vascular system (insufficient O2 supply) and a relative rise of O2 consumption (resulting from a marked increase of respiring cell mass as compared to that of the normal skin). In benign lesions, the latter factor is probably of primary importance. The low tumor O2 tension possibly affords tumors some protection against therapeutic radiation. Thus it appears reasonable that raising the low tissue O2 tension might improve the efficiency of X-ray therapy. Experiments to evaluate this are now in progress.