Introduction

In paediatric clinical practice, tests for urinary catecholamines and their metabolites are most often requested to aid in the diagnosis and follow-up of patients with neural crest tumours, particularly neuroblastomas.

Neuroblastoma is the most common extracranial solid tumour in children. Each year 80–90 new patients are diagnosed in the UK, most of them infants or toddlers. Neuroblastoma usually arises from either the adrenal medulla or the paravertebral sympathetic chain. It shows a wide variety of biological activity and has a correspondingly diverse range of presenting features and subsequent prognoses. Younger patients below 18 months of age generally have less aggressive forms of the tumour and require less intensive treatment, and indeed some children may not require any treatment as the tumour can spontaneously remit. In contrast, older children often present with more advanced and biologically aggressive forms of the disease and outcome is often poor despite very intensive treatment.

The presenting symptoms are usually dictated by the site of the primary tumour, sites of metastatic disease (bone marrow, bone, lymph nodes, liver, skin, brain and lungs) and possible hormone secretion. A suspicion of neuroblastoma is most typically raised in a child found to have abdominal, mediastinal or bone masses, or in a child with non-specific symptoms of lethargy, weight loss, recurrent infections or fever. Neuroblastoma should also be considered in any child with Horner's syndrome, opsoclonus-myoclonus syndrome or a persistent limp.

Phaeochromocytoma is another tumour which secretes catecholamines and can be either benign or malignant. These tumours are extremely rare in childhood, with only one or two new cases diagnosed in the UK each year, usually in teenagers. Presenting symptoms include sweating, palpitations, syncope, tremor and weight loss, which are all related to catecholamine secretion, although occasionally patients present with mass effect from the tumour. These patients often have hypertension, …