Endocrine Abstracts

Context: Distinct differences of clinical manifestations exist in hypertensive pheochromocytomas (HPs) and normotensive phaeochromocytomas (NPs), however the comparative analysis is lacking.

Objective: The objective of the study was to assess the clinical symptoms, haemodynamics, metabolism, radiological and histological features of patients with HPs and NPs.

Research design and methods: This retrospective study included 104 patients who underwent a unilateral adrenalectomy with a diagnosis of phaeochromocytoma at the Drum Tower Hospital Affiliated to Nanjing University Medical School from January 2004 to December 2014. All available clinical, biochemical, and radiological records were reviewed in phaeochromocytomas patients who were then categorized into HPs (n=69) and NPs (n=35) groups. Tumour samples were examined to determine the adrenal gland scale score and were available for measurement of gene transcriptions. Clinical and biochemical examinations of consecutive 95 subjects with primary hypertention (PH) were recorded for comparative study.

Results: Patients with NPs showed lower proportion of clinical triad, inapparent metabolic disorders and lower urinary catecholamine levels than HPs, but higher than PH. Tumour weight positively correlated with 24 h urinary norepinephrine level in patients with HPs (P=0.028), and tumour diameter negatively correlated with phenylethanolamine-N-methyltransferase (PNMT) immunohistochemistry (P=0.011) in NPs but not in HPs. The adrenal gland scale score of NPs group was similar to that of HPs group. The positive percentage of E-type of catecholamine in HPs group was higher than that in the NPs, while the positive percentage of NE-type or no function of catecholamine in HPs group was lower than that of the NPs. The transcript levels of PNMT, secretogranin II (SGII) and neuropetide Y (NPY) from tissue samples were significantly lower in NPs than in HPs, while vesicular monoamine trasporter 1 (VMAT1) had no difference between HPs and NPs.

Conclusions: HPs and NPs have distinct differences in clinical, biochemical and pathological phenotypes, which are closely related with the catecholamine pathway productions involved in tumour occurrence and development.