DETERMINATION OF REGIONAL TUMOR BLOOD FLOW BY KRYPTON-85

Krypton‐85 clearance techniques have been employed to determine regional blood flow in experimental tumors. Quantitative measurement of blood flow is simplified by the fact that Krypton is almost completely excreted in a single passage through the lungs, thus eliminating significant recirculation. To complete the calculations, it is first necessary to determine the partition coefficient of Krypton between blood and tumor tissue by a double‐isotope technique. Tumor tissue was saturated with Krypton when the animal inhaled the gas for 20 min. After inhalation was discontinued, clearance curves were recorded by beta count over the exposed tumor. This study confirmed previous reports that tumor blood flow is surprisingly low, averaging .29 ml/Gm/min. Clinical use of this method is possible in situations where a beta counter can be placed on the surface of the tumor. Copyright © 1968 American Cancer Society