An adrenal rest tumour in the perirenal region in a patient with congenital adrenal hyperplasia due to congenital 3beta-hydroxysteroid dehydrogenase deficiency.

BACKGROUND In contrast to the high incidence of testicular adrenal rest tumours (TART) in adult male patients with congenital adrenal hyperplasia (CAH), ovarian adrenal rest tumours in female CAH patients are very rare and other locations of adrenal rest tumours have never been reported. Here, we report on an adult patient with CAH due to 3beta-hydroxysteroid dehydrogenase (HSD) deficiency with bilateral TART and additionally a large perirenal adrenal rest tumour. CASE REPORT The patient was known with CAH due to 3beta-HSD deficiency and treated with hydrocortisone and fludrocortisone since the neonatal period. In puberty, there was lack of compliance with consequently high POMC concentrations. At the age of 16 years, bilateral TART were detected by scrotal ultrasound. Intensifying glucocorticoid medication did not result in decrease in POMC concentrations and shrinkage of size of the tumours. At the age of 23 years, abdominal ultrasound was performed because of abdominal complaints, showing a round inhomogeneous structure with a diameter of 4 cm near the left renal hilus. A computer tomography scan showed a multinodular lesion in the retroperitoneal region beside the left kidney. Histological investigation after removal of the tumour showed sheets of large polygonal cells with abundant eosinophilic cytoplasm, separated by dense fibrous tissue strands. The histological and immunohistochemical profile resulted in a diagnosis of an adrenal rest tumour. CONCLUSION In adult CAH patients, ectopic adrenal rest tumours can be present outside the testicular region. Further investigations are necessary to determine whether regularly screening for these tumours is useful.