18F-FDG PET reveals an adrenocortical carcinoma in a bilateral adrenal multinodular disease

Excerpt

A 48-year-old man underwent an abdominal computed tomography (CT) scan for asthenia. The CT scan revealed bilateral adrenal masses. The left mass measured 47 × 27 mm with a spontaneous density (SD) of -6 Hounsfield Unit (HU), in favor of a benign adrenocortical lesion (adenoma if < 10 HU). The right adrenal presented one anterior nodule of 28 × 23 mm with a SD of −25 UH, in favor of a benign lesion and a second posterior nodule of 21 × 25 mm, with a high SD of 27 UH and an absolute washout of 55% (> 60% in case of a benign lesion), consistent with an indeterminate lesion (Fig. 1a). The patient was lost of follow-up. After 1 year, the patient was referred to our hospital for hypertension, hypokalaemia and android obesity. Hormonal investigations showed an ACTH-independent hypercortisolism (Urinary free cortisol: 373 nmol/24 h (normal values:69-248), ACTH < 2 pmol/l (normal values 2 to 13)). The CT scan showed an increase in the posterior right adrenal mass (85 × 66 mm) with multiple retroperitoneal lymph nodes. The anterior right and left adrenal masses were unchanged (Fig. 1b).

…