Ultradian Steroid Rhythms in Adrenal Incidentalomas

Inclusion Criteria: * 18 \< Age ≤ 85 years. * Patient with one or more uni or bilateral adrenal nodules of cortical appearance on CT scan. * Subject affiliated or beneficiary of a social security scheme. The diagnostic criteria are: For the MACS group: * a serum cortisol concentration after a minute braking test with dexamethasone \> 50 nmol/L or 1.8 µg/dL, with a concomitant dexamethasone concentration above the test validation threshold * morning plasma ACTH concentration ≤ 2.5 pmol/L or 11 pg/mL. For the non-secreting adenoma group: \- Plasma cortisol after minute dexamethasone braking test ≤ 50 nmol/L or 1.8 µg/dL. Exclusion Criteria: * Age \< 18 years * Pregnant or breast-feeding * Use of oral estrogens (must be discontinued for at least 6 weeks prior to sampling) * Known adrenal insufficiency and/or treatment with steroids (oral, inhaled, parenteral or topical) or other interfering drugs. * patient taking part in another study * Patients placed under legal protection measures and/or deprived of their liberty