Biochemically silent normotensive colossal pheochromocytoma

A case presentation about rare giant pheochromocytoma of about a 50 year old female patient came to our out-patient department of general surgery with epigastric and right flank discomfort for past 1 day, abdominal distension and constipation for past 6 months. Patient’s blood pressure was normal without any postural variations and with no features of androgenic excess. All routine investigations were normal. Biochemical profile of urinary [VMA, metanephrine and normetanephrine], serum [cortisol, metanephrine, normetanephrine], serum aldosterone and plasma renin activity are measured normal. Contrast enhanced CT abdomen done suggestive of large well defined heterogeneously enhancing soft tissue lesion of size 21×22×28 cm noted involving abdominal cavity more on right side arising from right lumbar region was identified. Patient underwent exploratory laparotomy and identified that mass was arising from right adrenal gland and right kidney which was difficult to be dissected from the mass, for which right nephrectomy was also done along with mass removal of size 28×28×20 cm and weight of 4200 gm. Postoperative period was uneventful. Histopathological examination showed gross feature of single large encapsulated globular structure with right kidney attached to it. Mass was encapsulated with total size of 24×25×14 cm, greyish in colour and soft to firm in consistency. On cut section focal areas of greyish yellow friable tissue with few small cystic areas, large hemorrhagic area and focal greyish white areas was seen. Microscopic feature of these tumor cells was arranged in well defined nests (zellballen) bound by highly vascularized stroma. Cells were polygonal shaped with finely granular amphophilic cytoplasam, round to oval nuclei with salt and pepper chromatin and at places prominent nucleoli were seen. Special staining with PAS done and it was negative.