DEFINITION OF HEPATIC TUMOR MICROCIRCULATION BY SINGLE PHOTON-EMISSION COMPUTERIZED-TOMOGRAPHY (SPECT)

Abstract

Single photon emission computerized tomography coupled with 99mTc MAA [macroaggregated albumin] heptic-arterial perfusion scintigraphy was used to examine the density of the functional microcirculation of hepatic tumors relative to normal liver in 24 patients. In both colorectal and carcinoid tumors an average 3-fold greater arteriolar-capillary density was demonstrated in areas of tumor proliferation. The depth of the evoked tumor hypervascularity extended .apprx. 4 cm. Tumors greater than 8-9 cm in diameter uniformly had a central hypovascular core. These observations are of importance in the design of selective strategies utilizing therapeutic microspheres directed against the hypervascular proliferating regions of human tumors.