Background: Individuals with neurofibromatosis type-1 (NF1) carry an increased risk of pheochromocytoma (PHEO). Detection strategy is unknown but most experts recommend screening if hypertension develops.
Objective: Report the characteristics of PHEO in patients with NF1 (NF1 group) and compare them with non-NF1-associated PHEO (non-NF1 group).
Methods: Retrospective cohort study of patients undergoing PHEO resection in two Spanish tertiary hospitals, from 19802016.
Results: Of 78 patients undergoing PHEO resection, 5 (6.4%) had NF1. NF1 patients were younger than those with non-NF1 (mean age 41.8 vs 52.5 yr, P=0.068). Males comprised 60% versus 40% of the NF-1 group and non-NF1 group, respectively. PHEO was incidentally diagnosed in 3 of 5 (60%) from NF1 group and only in 29 of 73 (39.7%) from non-NF1 group (P=0.395). Remaining NF1 cases were diagnosed by screening (hypertension, n=1) and compatible adrenergic clinic (n=1). Hypertension was present in 2 (40%) NF1 patients and in 33 (45%) non-NF1 patients. Urinary and/or plasma catecholamines were elevated in all NF1 patients and in 55 (88%) of non-NF-1 group. There was no significantly difference (P=0.207) in tumor size between both groups of patients (median 4.6 cm vs 5.6 cm in NF1 and non-NF1 patients, respectively).
Conclusion: In our series, age at diagnosis and gender were similar in NF1 and non-NF1 PHEO patients. NF1-associated PHEO is diagnosed incidentally in more than half of the patients. Although all NF1-PHEO tumors were functioning, only two of five patients had hypertension. It is necessary to keep in mind the possibility of developing PHEO in NF1 patients even in those non-hypertensive patients. On the contrary, in all patients with PHEO is advisable to search clinical criteria used to diagnose NF1, and thus confirming an often-delayed diagnosis.
20 - 23 May 2017
European Society of Endocrinology