Biodistribution of radioactive epidermal growth factor in normal and tumor bearing mice.

The biodistribution of iodinated epidermal growth factor in normal and tumor bearing mice was analyzed. The uptake of epidermal growth factor was high in the liver, skin and submaxillary gland, which all have detected receptors for the growth factor. Organs, such as lung, heart, spleen, intestine, bone and central nervous system, which lack the receptor, did not retain the growth factor. In tumor bearing mice, the growth factor accumulated in receptor positive tumors, but to a lesser extent than in the liver. This finding will probably prevent the use of epidermal growth factor as a carrier for radionuclides for a therapeutic purpose.