Endocrine Abstracts

Introduction: Pheochromocytoma is a rare tumor originating from chromaffin cells of the adrenal medulla secreting catecholamines. The typical symptoms of pheochromocytoma include hypertension, headache, heart palpitations, anxiety, and profuse sweating. However, some patients with pheochromocytomas remain asymptomatic. The aim of this study was to determine the clinical and paraclinical characteristics of incidentally discovered pheochromocytomas.

Methods: This was a single center retrospective study including patients with confirmed pheochromocytoma. Clinical and paraclinical data were recorder from patients’ medical files. Patients were divided into two groups: group 1: patients with incidentally discovered pheochromocytoma and group 2: patients with clinically patent pheochromocytoma.

Results: Fifty-three patients with pheochromocytoma were enrolled in this study. Pheochromocytoma was incidentally discovered in 43 % of cases (n=23, 12 women and 11 men). The median age was 51 years (IQR: 36 – 56) in group 1 and 47 years (IQR: 31 – 55) in group 2 (P=0.271). There was no statistical difference between the two groups regarding the prevalence of overweight, obesity, and diabetes. Among the clinical findings, the symptom triad made of headache, palpitations and profuse sweating was found in 13% of cases in group 1 and in 57% of cases in group 2 (P=0.001). The prevalence of hypertension was 30% in group 1 and 83% in group 2 (P<0.001). Systolic (P=0.043) and diastolic (P=0.029) blood pressure levels were significantly higher in group 1 than in group 2. The majority of tumors in the two groups secreted normetanephrines only. The blood levels of normetanephrines were 6.5 times the normal range (IQR: 3.5-14.8) in group 1 and 7.15 times the normal range (IQR: 3.6-10.1) in group 2 (P= 0.642). The median size of the tumor was 50.5 mm (IQR: 38.1-70.5) in group 1 and 49.5 mm (IQR: 37.5-64.7) in group 2 (P=0.734). Pheochromocytoma was malignant in 35% of cases in group 1 and 22% in group 2 (P=0.392).

Conclusions: It is important to explore all adrenal incidentalomas since some of them turn out to be silent pheochromocytomas and therefore need as much of an urgent management as the clinically patent ones.