A case report on asymptomatic and biochemically silent pheochromocytoma in adrenal incidentaloma

Abstract

Pheochromocytoma are rare tumours originating from the chromaffin tissue. The clinical manifestations are variable and are not specific as pheochromocytoma and often imitate other diseases. The diagnosis is established by measurement of catecholamines and their metabolites in urine or plasma and by radiographic studies for localisation. Surgical removal of the tumour is the preferred treatment. 45 years old female presented with adrenal incidentaloma of about 6.1×6.2×5.4 cm well defined heterogenous lesion with internal cystic areas seen in right adrenal region abutting upper pole of right kidney. Biochemical investigations for adrenal hormones including plasma aldosterones, cortisols, plasma metanephrines, 24 hrs urinary metanephrines and VMA were found to be normal. Proceeded with adrenelectomy and histopathology of the specimen revealed pheochromocytoma as diagnosis. Pheochromocytoma leads to high mortality and morbidity rates if untreated. Fractionised metanephrines and catecholamines in a 24 hrs urine analysis is the preferred biochemical test. In a biochemically silent pheochromocytoma imaging modalities are used to identify and locate the tumour. Adequete alpha and beta blockade should be ensured before tumour removal. Surgery is recommenced irrespective of size and normal biochemical study to prevent complications.