Is growth hormone treatment beneficial or harmful in Costello syndrome

Costello syndrome (CS) was first described by Costello in two unrelated children, in 1971 and 1977.1 The major manifestations of CS have been summarised as postnatal growth deficiency, developmental delay, relative macrocephaly, coarse face, thick ears, thick lips, depressed nasal bridge with anteverted nares, excess skin, thick palms and soles, short neck, curly hair, nasal papillomata, and sociable personality.2 Recently, it has become apparent that children with CS have an increased risk of malignancy, particularly rhabdomyosarcoma. Rhabdomyosarcoma, predominantly embryonal, has been reported in 10 children, ganglioneuroblastoma in three, bladder carcinoma in two, epithelioma in one, and acoustic neuroma in one adult.3 A further three unpublished cases of rhabdomyosarcoma in children with CS are known to us through the International Costello syndrome support group and a fourth case is included in this report (case 2). The frequency of tumours in CS has been estimated to be as high as 17%3 and a screening protocol has been proposed. These recommendations for surveillance include three to six monthly abdominal and pelvic ultrasound until the of the age of 8–10 years, urinary catecholamine analysis every six to 12 months until the age of 5, and annual urine analysis after the age of 10. Whether or not abdominal ultrasound would enable detection of early stage disease in rhabdomyosarcoma with a benefit for both survival and morbidity is unknown. For neuroblastoma, however, data from the general population suggested that screening had no impact on mortality or morbidity and the use of urine analysis in detection of bladder cancer has not been evaluated.4 Evaluation of the risks and benefits of the suggested screening regimen in this rare disorder will require in the first instance a network of collaborating geneticists and parents who are willing to allow screening without proven benefits.4 Cardiac …