FRI192 Serum Steroid Biomarkers For The Differential Diagnosis Of Adrenocortical Carcinoma (ACC) And Adrenocortical Adenoma (ACA)

Disclosure: D. van Rooyen: None. R. Scheske: None. A.M. Lerario: None. W.E. Rainey: None. R.J. Auchus: None. G.D. Hammer: None. T. Else: None. Background: Adrenal tumors are very common, with the vast majority being benign adrenocortical adenomas (ACA). Adrenocortical carcinomas (ACC) represent only a very small proportion of adrenal tumors. Distinction between the common ACA and rare ACC relies on invasive and costly protocols which are often inconclusive. Research into the use of steroid biomarkers as a non-invasive alternative diagnostic tool has been the focus of various steroid metabolomics studies. In this study, we aimed to identify serum steroid biomarkers to distinguish ACA from ACC. Methods: This study population was comprised of 103 patient samples, including 45 (31 female) and 58 (40 female) respective samples from ACA (age 32-90) and ACC (age 16-77) patients presenting with disease at the time of sampling. No ACC patients studied had been treated with mitotane. Serum steroid levels (4 sulfates and 25 Δ4 steroids) were measured using liquid-chromatography tandem mass spectrometry (LCMS/MS) with comparisons made between steroid profiles in ACA vs ACC and between males and females within each group (ACA and ACC). Data were analyzed to obtain the geometric means with 95% CIs, and statistical significance was determined using a two-tailed Mann-Whitney test. Results: ACC patients were characterized by significantly elevated levels of pregnenolone-sulfate, 17hydroxypregnenolone-sulfate, 11-deoxycorticosterone, 17hydroxyprogesterone, and androstenedione when compared to ACA patients. In addition, steroid levels differed between male and female samples, with dehydroepiandrosterone-sulfate (p