Visualization of lung metastatic lesion from malignant melanoma by N-isopropyl-p-123I-iodoamphetamine

A patient with malignant melanoma was examined with N-isopropyl-p-I-123-iodoamphetamine (I-123 IMP) whole body scintiscanning for the detection of metastatic lesions. Uptake of I-123 IMP was noted at 3 to 18 hours after iv injection in the right upper lung field, corresponding to the findings of chest X-ray tomography. Scintiscanning revealed an inhibition of tumor uptake of I-123 IMP when combined with iv injection of L-DOPA. Both delayed scanning and L-DOPA loading may provide useful information concerning not only the location of lesions but also uptake mechanism of I-123 IMP in malignant melanoma. (Namekawa, K.)