No overrepresentation of congenital adrenal hyperplasia in patients with adrenocortical tumours

OBJECTIVE The development and progression of sporadic adrenocortical tumour s are poorly understood. In autopsy studies adrenocortical tumours are foun d in between 2 and 9% of the general population. In congenital adrenal hype rplasia (CAH), decreased production of cortisol leads to increased secretio n of ACTH from the pituitary, resulting in hyperplasia of the adrenals, Mor e than 95% of all cases of CAH are due to steroid 21-hydroxylase deficiency , resulting from mutations in the CYP21 gene, In subjects homozygous and he terozygous for CYP21 mutations, adrenocortical tumours have been found in a high frequency compared to the general population, suggesting that chronic ACTH stimulation may play a role in the development of this tumour form. I n order to test whether mild undiagnosed CAH is a common predisposing facto r, we screened 27 patients with sporadic adrenocortical tumours for CYP21 m utations. DESIGN A retrospective study. PATIENTS We screened 27 patients with sporadic adrenocortical tumours, repr esenting both benign and malignant as well as hormonally active and silent lesions. MEASUREMENTS Mutation analyses of the CYP21 gene was performed by allele-sp ecific PCR on high molecular weight DNA, The method used detects the nine C YP21 mutations that are responsible for 95% of all disease-causing alleles in CAH. RESULTS No mutations were detected in any of the 23 DNA samples that were p repared from leucocytes. In 4 cases where no leucocyte DNA was available, t umour tissue was analysed, In one of these tumours, two CYP21 mutations, V2 81 L and L307insT, were found in heterozygous form. CONCLUSION Our data indicate that mild undiagnosed congenital adrenal hyper plasia is not a common underlying factor predisposing to adrenocortical tum ours, at least not in the Swedish population.