OctreoScan Liver Uptake: Somatostatin Receptors

On this Octreoscan, focal uptake is seen in the liver at both 4 and 24 hours. What receptor does In-111 pentetreotide bind to, allowing it to accumulate in these lesions?

1. ASomatostatin receptors, which are overexpressed on the surface of most neuroendocrine tumors such as carcinoid and islet cell tumors
2. BDopamine D2 receptors, which are expressed at high levels in neuroendocrine tumors due to their shared neural crest cell origin
3. CEpidermal growth factor receptors, which are upregulated in rapidly dividing neuroendocrine tumor cells throughout the liver and abdomen
4. DAdrenergic receptors, similar to the mechanism used by MIBG, since both agents target tumors derived from the autonomic nervous system