Endocrine Abstracts (2016) 40 P20 | DOI: 10.1530/endoabs.40.P20

The importance of fully investigating adrenal incidentaloma: two pheochromocytoma cases

Diana Oliveira, Sandra Paiva, Isabel Paiva, Dírcea Rodrigues, Daniela Guelho, Luís Cardoso, Nuno Vicente, Diana Martins, Adriana Lages, Mara Ventura & Francisco Carrilho


Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.


Introduction: In most cases, adrenal incidentalomas are non-functioning adrenocortical adenomas, but may also represent conditions in which therapeutic intervention is essential, such as pheochromocytomas, even with low index of suspicion.

Case reports: Case report 1. Fifty-three-year-old male with history of arterial hypertension (HT), type 2 diabetes Mellitus and myocardial infarction, with a right adrenal incidentaloma found in abdominal ultrasound in February/2011. Abdominal CT revealed a 36 mm nodule in the right adrenal gland with solid homogeneous density. The preoperative analytical study was normal, including values of urinary fractionated metanephrines. In 2012 the control abdominal CT continued to show a nodule with the same characteristics, ‘suggestive of adrenal adenoma’, 40 mm. The patient underwent laparoscopic right adrenalectomy on 22 October 2013. Pathology report diagnosed ‘pheochromocytoma’. Although he did not undergo preoperative adrenergic receptor blockade, he maintained hemodynamic stability throughout the surgical intervention and the postoperative period. The analytical study after the adrenalectomy was normal, with normal metanephrine levels and no adrenal insuffiency. Genetic testing did not find any clinically relevant mutations.

Case report 2. Fifty-year-old female with no relevant medical history. Right adrenal incidentaloma found in abdominal ultrasound in January 2015. Abdominal CT showed a well defined 35 mm nodule, with characteristics suggestive of adrenal adenoma. Preoperative investigation revealed significantly elevated plasma free and urinary fractionated metanephrines. She underwent laparoscopic right adrenalectomy on 28 October 2015; the pathology report confirmed a pheochromocytoma, with no criteria for suspicion of malignancy (PAS Score <4). Postoperative study showed normalization of metanephrine values and absence of adrenal insufficiency. Genetic testing result is pending.

Conclusion: Both the cases concern patients with an incidentally found adrenal mass, who did not have the typical signs and symptoms of pheochromocytoma. In case 1, we describe a man with HT but no other symptoms and no biochemical evidence of catecholamine hypersecretion, and the patient in case 2 had a completely silent tumor. Both had abdominal CT sugestive of adenoma. As these case reports illustrate, the exhaustive evaluation of all adrenal incidentalomas is leading to a rising prevalence of diagnosed pheochromocytomas, allowing for safer surgical procedures and reducing immediate and long lasting morbidity and mortality.