Clinical use of somatostatin analogues in paediatric oncology.

Paediatric oncology continues to search for improved methods for the early detection and effective treatment of solid tumours, especially those of the nervous system, which constitute 50% of all solid tumours in children and adolescents. These tumours, including neuroblastoma, meningioma, low-grade astrocytoma and medulloblastoma express somatostatin receptors and can be imaged effectively using 111In-octreotide. In addition to improved imaging techniques, somatostatin analogues are being developed for use in radioreceptor-guided surgery, as a component of adjuvant chemotherapy and for supportive treatment. Radioreceptor-guided surgery utilises 125I-Tyr3-octreotide or 125I-lanreotide to detect tumour foci within minutes of injection. It allows the detection of 0.1-1.0 mg tumour (1 x 10(5) to 1 x 10(6) tumour cells). This technique has successfully located foci of occult tumour in children with neuroblastoma. Somatostatin analogues are also currently being studied as tumour growth inhibitors between regular chemotherapy cycles and for the treatment of chemotherapy-induced pancreatitis in children with leukaemia. Research on somatostatin receptor subtype expression in paediatric tumours suggests that further investigation of analogue effects on growth inhibition and induction of differentiation will contribute to improved therapy for children with solid tumours.