Endocrine Abstracts

An adrenal incidentaloma >4 cm of size is considered suspected of malignancy and therefore often sent to the adrenalectomy for pathological verification. In these cases, in recent studies the role of 18F-FDG-PET / TAC has been evaluated. We report a case of 67 years old man hospitalized for abdominal pain, fever and oliguria in obese patient with a history of diabetes mellitus 2, chronic renal failure, arterial hypertension and subjected to PTCA about 10 years earlier for anterior descending coronary stenosis. The abdominal ultrasound shows hepatic steatosis, many microstones of the gallbladder and an adrenal lesion of about 4 cm. Blood and uroculture detect a gram positive sepsis and laboratory tests show a cholestatic jaundice with moderate hyperamylasemia as well as renal failure and worsening glycemic control. After a few days of adequate therapy with a marked improvement in clinical conditions and laboratory tests, the patient undergoes, a cholangioMRI that detects, in addition to cholelithiasis, a solid right adrenal lesion of 4.8 cm, without adipose content and with non-homogeneous enhancement. The 18F-FDG PET/CT in the suspicion of a malignant lesion has been performed which showed a hypermetabolism of the right adrenal adrenal lesion (SUV max 12.8). There was non uptake in other lesions. The dosage of adrenal hormones showed a pre-clinical hypercortisolism ACTH-indipendent with normality of mineralocorticoid serum levels and urinary metanephrines. The patient was sent to laparoscopic cholecystectomy and right adrenalectomy. The morphological and immunophenotypic pathological analysis show a picture of a mixed type adrenal oncocytoma.

In conclusion: 1. It is confirmed that adrenal incidentalomas >4 cm may not be malignant.

2. Also the 18F-FDG-PET/TAC positivity is not always specific to malignant lesion.

3. The adrenal oncocytoma, very rare adrenal tumor usually benign and non-functioning, can be considered in these cases.