Endocrine Abstracts

Introduction: Phaeochromocytoma (PCC) constitutes a rare but clinically significant catecholamine-secreting neoplasm of chromaffin cell origin, predominantly arising within the adrenal medulla. Its incidence in the paediatric population is exceedingly low (0.2–0.3 cases per million children), yet it bears substantial morbidity due to hypertensive crises and catecholamine-induced cardiomyopathy. This report delineates two phenotypically divergent paediatric cases, underscoring the diagnostic complexity, variable clinical trajectories, and therapeutic strategies necessitated by this neuroendocrine tumour.

Case presentation: The first case involves a 6-year-old male presenting acutely with fever, dyspnoea, and paroxysmal tachyarrhythmia. Cardiological evaluation revealed dilated cardiomyopathy with a severely depressed ejection fraction (26%). Biochemical profiling demonstrated markedly elevated plasma and urinary normetanephrines and vanillylmandelic acid. Cross-sectional imaging identified a right-sided adrenal mass, and subsequent laparoscopic adrenalectomy confirmed PCC with a high Phaeochromocytoma of the Adrenal gland Scaled Score (PASS = 9), suggestive of aggressive biological behaviour. Loss of succinate dehydrogenase complex subunit B (SDHB) immunoreactivity and a pathogenic variant in the Von Hippel-Lindau (VHL) gene were consistent with syndromic PCC. The patient remains under oncological surveillance three years postoperatively. Conversely, the second case describes a 13-year-old male with a pre-existing bicuspid aortic valve who presented with headache, dizziness, and sustained hypertension. Biochemical indices revealed substantial catecholaminergic excess; Contrast MRI delineated a 4 cm right adrenal tumour. Despite initial intolerance to phenoxybenzamine, he achieved haemodynamic stability with doxazosin prior to successful laparoscopic resection. Histopathology confirmed PCC with loss of SDHB staining and a moderate PASS score (4), predicting risk of recurrence. Genetic screening was negative for common susceptibility loci, and the patient has entered routine follow-up.

Conclusion: These cases exemplify the phenotypic breadth and genetic underpinnings of PCC in childhood. They reinforce the imperative for heightened clinical vigilance in hypertensive children, especially in the context of cardiac dysfunction or ambiguous symptomatology. Prompt biochemical and radiologic evaluation, judicious preoperative alpha-adrenergic blockade, and precise surgical intervention remain cornerstones of optimal paediatric PCC management.