Tumor visualization with a radioiodinated phospholipid ether.

Abstract

The known ability of phospholipid ethers to accumulate in certain tumors prompted the synthesis and evaluation of a radioiodinated phospholipid ether analog as a potential tumor imaging agent. Tissue distribution studies with [125I]-rac-1-0-[12-(m-iodophenyl)dodecyl-2-0-methylglycero-3- phosphocholine in rats bearing the Walker 256 carcinosarcoma showed the tumor to contain the highest concentration of radioactivity at 24 hr (15% of the dose) and a tumor-to-blood ratio of 13. Scintigraphic images taken at 24 hr compared favorably with those obtained with (67Ga)-citrate. In contrast with the latter, however, the phospholipid ether showed little propensity to accumulate in an inflammatory lesion in the rat. Tumor visualization was also accomplished in a rabbit bearing the V x 2 adenocarcinoma. We conclude that phospholipid ethers may represent a new class of carrier molecules for the transport of radionuclides to tumors.