'Great Masquerader': a history of diagnosing pheochromocytoma.

Introduction: Pheochromocytoma is a unique tumour with a variety of clinical presentations. Coined as 'the great masquerader', it can present with the classical triad of headache, sweating and tachycardia and sometimes in an acute hypertensive crisis. This paper describes the evolutionary history of the diagnosis of this condition.

Methods: A literature review was conducted using Medline Database from 1900 to 2023 outlining the methods of diagnosis for pheochromocytoma.

Results: There have been diagnostic dilemmas and localization challenges of pheochromocytoma over the last century. From the first description of pheochromocytoma in 1886 to the first successful resection in 1926, there was poor recognition of its atypical symptoms and lack of reliable diagnostic tests. Over the next few decades, there were significant advances in screening and biochemical tests. Further understanding of catecholamine release and metabolic pathways led to the development of tests to identify end products of catecholamine metabolism in plasma and urine. Computed imaging however heralded significant improvement in surgical planning and management. The evolution of histopathological diagnosis with the use of immunostains and genetic testing has further contributed to the identification of malignant pheochromocytomas and an understanding of their behaviours.

Conclusion: Significant advances in the biochemical and imaging have shaped our understanding of pathophysiology and management. These diagnostic advances have enabled early and accurate detection and localization of pheochromocytomas to enable prompt surgical management.