Endocrine Abstracts

Case History: A 53 year old woman presented with a 12-month history of progressive hirsutism and deepening of her voice. Her symptoms coincided with the onset of the menopause. On clinical examination she had evidence of virilisation with muscle hypertrophy.

Investigations: Biochemical tests revealed a serum testosterone (serT) of 30 nmol/l, a DHEA-Sulphate of 1.5 umol/l (1.0–12.0), an androstenedione of 3.2 nmol/l (0.0–6.0), a post-overnight dexamethasone suppression test cortisol of <50 nmol/l (and corresponding serT of 40 nmol/l), aldosterone : renin ratio of 159. Urinary metabolites were normal apart from slight elevation in androgen metabolites, androsterone-5 beta 1880 ug/24 h (260–1270) and aetiocholanolone of 2260 ug/24 h (270–1390). An abdominopelvic CT scan showed a 2.4 cm right adrenal mass and this was corroborated on an adrenal MRI scan. Due to the presence of the adrenal adenoma we performed adrenal vein sampling (AVS) with ovarian and peripheral venous samples (without ACTH-stimulation) in order to exclude a testosterone-secreting adrenal adenoma.

Results and treatment: AVS measurements of testosterone using Liquid Chromatography with tandem mass spectrometry showed testosterone values of 3803, 30, 20.1 and 29.9 nmol/l for the right adrenal vein (RAV), left adrenal vein (LAV), inferior vena-cava (IVC) and left ovarian vein (LOV) respectively. Attempted cannulation of the right ovarian vein was unsuccessful. Serum cortisol measurements in the RAV, LAV and IVC were 824, 24 033 and 216 nmol/l, respectively which provided selectivity indices of 4 for the RAV and 111 for the LAV, both which confirmed adequate cannulation. This was further confirmed by marked differences in metanephrine levels between the RAV (20 897 pmol/l), LAV (23 459 pmol/l) and IVC (99 pmol/l). Following AVS GnRH analogue therapy, Goserelin, was introduced to assess for a response in testosterone with gonadotrophin suppression after which there were weekly measurements of testosterone and gonadotrophins. Four weeks following treatment with Goserelin there was suppression of her gonadotrophins and improvement in the serT to 1.3 nmol/l.

Conclusions and points for discussion: Our results suggest a single testosterone-secreting right adrenal adenoma that responded to gonadotrophin suppression.

Points for discussion are: 1. Reviewing the AVS results with the response to GnRH analogue therapy what are the possible mechanism for this; could there be an HCG or other gonadotrophin-responsive receptor expression on the adrenal nodule?

2. What further investigations would be indicated?

3. Is there sufficient evidence to proceed with a right-sided adrenalectomy?