Endocrine Abstracts

Objective: An adrenal incidentaloma is discovered in about 3–4% of patients undergoing radiological examination (CT/MRI) of the abdominal region. Current diagnostic algorithms for differentiating between benign and malignant lesions largely depend on imaging studies, which lack in specificity. This often leads to extended radiological follow-up of benign lesions, which is time-consuming, expensive and carries a health risk. It was recently suggested that urinary steroid profiling using gas-chromatography/mass-spectrometry (GC/MS) might be a valuable diagnostic test regarding this clinical problem. We present a large clinical series to test this hypothesis.

Methods: Urinary steroid profiles from patients with adrenal enlargement evaluated between 01-01-2000 and 01-11-2011 were collected. The concentrations of 22 metabolites were measured using GC/MS in 24-hour urine samples. Patient’s records were studied and information was collected regarding symptoms and signs, laboratory measurements, imaging studies, treatment, pathology reports and clinical outcome. Steroid profiles were analyzed by calculating receiver operating characteristics (ROC) for every individual metabolite.

Results: In our population of 155 patients, we found significantly higher concentrations of eighteen metabolites in patients with ACC (n=18) compared to patients with other adrenal conditions. Tetra-hydro-deoxycortisol (THS) distinguishes ACC from other adrenal disorders with 100% sensitivity and specificity at a cut-off value of 2.95 μmol/24 h.

Conclusion: Our results confirm earlier findings, which suggest that measuring urinary excretion of THS can be useful in differentiating adrenocortical carcinoma from other adrenal tumors. The technique of GC/MS is reliable, non-invasive and less expensive than repeated imaging studies. The next step is prospective validation of this diagnostic tool.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.