Catecholamine hypersecretion, also known as pheochromocytoma, originates in the adrenal medulla, sympathetic ganglion, parasympathetic ganglion (paraganglia) or other sites of chromophobic tissue. Due to the paroxysmal or persistent secretion of norepinephrine and epinephrine by the tumor cells, the clinical picture is one of paroxysmal or persistent hypertension, headache, sweating, palpitations and metabolic disorders. Pheochromocytoma can be cured if treated early. Pheochromocytomas located in the adrenal glands account for 80% to 90% of cases and are mostly one-sided; extra-adrenal tumors are mainly located in the extra-peritoneal area and parietal aorta (10% to 15%), and a few are located in special areas such as the hilum, hepatic hilum, bladder and retrorectum. Most of them are benign and 10% are malignant. As with most tumors, the etiology of disseminated pheochromocytoma remains unclear. Familial pheochromocytomas, on the other hand, are genetically related. Pheochromocytomas in multiple endocrine adenomatosis (MEN-2A, MEN-2B) have been reported to have a deletion of the short arm of chromosome 1, and both have been found to have germ-line mutations in the REI proto-oncogene on chromosome 10, with MEN2A showing a mutation in exon 10 of RET, which encodes a cysteine residue in the ligand-binding region of the extracellular protein cysteine residues that affect the tyrosine kinase receptor on the cell surface, while MEN-2B has a mutation in the RETB proto-oncogene on chromosome 10, which affects the tyrosine kinase catalytic site in the intracellular protein binding region. Tyrosine kinases are implicated in the regulation of cell growth and metamorphosis. This leads to the development of the disease in susceptible individuals. The diagnosis of pheochromocytoma is based on blood and urine measurements of catecholamines and their metabolites but because the incidence of pheochromocytoma is not high in patients with hypertension, it is not possible to screen every patient with hypertension and some patients with pheochromocytoma do not have hypertension Diagnostic testing should be performed if there are: typical episodes of pheochromocytoma-like symptoms and hypertension is present; Hypertension that does not respond well to conventional antihypertensive medications; malignant hypertension or acute hypertension (retinal exudative changes or with optic disc edema); episodes of hypertension caused by the use of antihypertensive medications, especially after the application of beta-blockers; episodes of hypertension caused by exercise, surgical induction of anesthesia to intubate and pull abdominal organs during delivery or the application of contrast media; a family member with pheochromocytoma or a familial MEN; blood pressure very variable (e.g., alternating hypertension-hypotension); spontaneous postural hypotension; imaging findings of unexpected adrenal tumors.