1 Department of Medical Sciences, Section of Endocrine Oncology, University Hospital, Uppsala, Sweden
2 Department of Oncology, Radiology and Clinical Immunology, Section of Nuclear Medicine, University Hospital, Uppsala, Sweden
Abstract:
To investigate possible changes in somatostatin receptor expression during treatment with high dose lanreotide, eight patients with neuroendocrine tumors were investigated by 111In-DTPA-D-Phe1]-octreotide scintigraphy before and during treatment. The spleen-to-background ratio decreased in all patients, whereas tumor-to-background ratio revealed a heterogeneous pattern with an average increase of 50% (−79% to +1,087%). This finding indicates that lanreotide treatment may influence the binding of radioactively labeled somatostatin to the spleen, while changes in the binding to functioning somatostatin receptors in tumor cells are more complex and not clearly related to treatment.