The use of radioiodinated alpha-fetoprotein for the scintigraphic detection of mouse mammary carcinomas.

Alpha-fetoprotein (AFP) is taken up by developing fetal cells but not by normal adult cells. This finding together with the resemblance between fetal cells and cancer cells suggests that malignant tissue could incorporate AFP in opposition to normal tissue. In the present work, we injected mice bearing spontaneous mammary adenocarcinomas with 131I-radioiodinated AFP. The scintigraphic images obtained with a gamma camera showed that 11 out of 12 carcinomas displayed strong radiolabelling with very low activity in the surrounding normal tissues. In addition, three non-neoplastic cystic lesions were found to be negative. The future implications of this result for tumour diagnosis, as well as the possible mechanisms of AFP uptake are discussed.