A 40-year-old man presented with history of episodic palpitations and headaches. The patient was fine until 1 year back when the patient staed experiencing spells of rapid heabeat. These became more severe and were eventually accompanied by throbbing headaches and drenching sweats. Physical examination revealed a blood pressure of 154/94 mm Hg and hea rate of 86 bpm. During the physical examination, palpation of the abdomen elicited a sudden and typical episode, with a rise in blood pressure to 214/128 mm Hg, hea rate to 128 bpm, profuse sweating, and facial pallor. This was accompanied by severe headache. MRI and PET SCAN is given below. Which of the following is true regarding the patient's condition?
Episodic palpitations with throbbing headaches and profuse sweating with hypeension and tachycardia is pointing towards the clinical diagnosis of pheochromocytoma. MRI/ 18-F-DOPA findings are suggestive of pheochromocytoma. Rule of 10s for pheochromocytoma: - Ten percent of pheochromocytomas are extra-adrenal (occurring in sites such as the organs of Zuckerkandl and the carotid body) Ten percent of sporadic adrenal pheochromocytomas are bilateral. Ten percent of adrenal pheochromocytomas are biologically malignant, Ten percent of adrenal pheochromocytomas are not associated with hypeension. The most sensitive test to diagnose pheochromocytoma is estimation of plasma levels of metanephrines. Histopathologically, the tumor consists of clusters of polygonal or spindle shaped chromaffin cells suppoed by sustentacular cells in a nest like pattern which is also known as Zellballen pattern. Phenoxybenzamine is an irreversible alpha-adrenergic blocker is used in the treatment of pheochromocytoma. Phentolamine is a reversible alpha-adrenergic blocker is used as a challenge test in diagnosis of pheochromocytoma.
10% of these tumours are unilateral
24-hour urinary excretion of VMA is the most sensitive test to diagnose this condition.
Histopathologically, the tumor consists of clusters of polygonal or spindle shaped chromaffin cells suppoed by sustentacular cells in a nest like pattern.
Phenoxybenzamine is a reversible alpha blocker, hence used in the challenge test to diagnose this condition.
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