Octapeptide somatostatin-analogue therapy of Cushing's syndrome

The currently available octapeptide somatostatin analogues octreotide (Sandostatin, Sandostatin LAR, Novartis, Basle, Switzerland) and somatuline (BIM 23014, Lanreotide, Beaufort-Ipsen, Paris, France) have beneficial effects in the treatment of various neuroendocrine tumour syndromes. These effects are mediated through specific membrane-associated somatostatin receptor subtypes (ssts) on the target tissues.1 Five different sst subtypes (sst1–5) have been cloned and characterised, and it was demonstrated that octapeptide somatostatin analogues bind with a high affinity to sst2 and sst5, show a low affinity to sst3, but no affinity to sst1 and sst4.1 Tumours and metastases, which bear receptors for octapeptide analogues, can be visualised in vivo using gamma camera pictures obtained after injection of 111In-pentetreotide (OctreoScan, Mallinckrodt, Petten, The Netherlands).1 View this table: Table  Pentetreotide scintigraphy for the detection of occult ectopic ACTH-secreting tumours The possible therapeutic effects of octreotide have been studied in the different subclasses of Cushing's syndrome. Cushing's disease, which exclusively stands for the excessive secretion of (adreno)corticotropin (ACTH) by the pituitary, is the main variant of Cushing's syndrome, representing about …