Response to treatment with yttrium 90-DOTA-lanreotide of a patient with metastatic gastrinoma

1,4,7,10-tetraazacyclododecane-N,N',N ",N"'-tetraacetic acid (DOTA)-lanreot ide is a universal somatostatin (SST) receptor subtype ligand that binds to a large variety of human tumors. We report the case of a patient with meta static gastrinoma who was treated with Y-90-DOTA-lanreotide. Before treatme nt, dosimetry with In-111-DOTA-lanreotide (150 MBq, 10 nmol) indicated a do se of 5.8 mGy/MBq for the recurrent abdominal gastrinoma, and a mean dose o f approximate to 1.0 mGy/MBq for liver metastases (i.e., 56 and approximate to 10 mGy/MBq for Y-90-DOTA-lanreotide, respectively). After four infusion s of Y-90-DOTA-lanreotide (each 1 GBq, approximate to 30 nmol) over a 6-mo period, the In-111-DOTA-lanreotide scintigraphy of the liver had returned t o a nearly normal condition and a remarkably decreased uptake by the recurr ent gastrinoma was calculated (approximate to 5 mGy/MBq for Y-90-DOTA-lanre otide). The imaging results were well-correlated with a 25% regression of t he liver metastases as indicated by CT. Blood, urine and whole-body clearan ces of In-111-DOTA-lanreotide and Y-90-DOTA-lanreotide were very similar. T he DOTA-lanreotide promises to be useful for functional tumor diagnosis (In -111-DOTA-lanreotide) and receptor-mediated tumor radiotherapy (Y-90-DOTA-l anreotide).