嗜铬细胞瘤 英语读片

Pheochromocytoma
Pheochromocytoma (PCC) is a neuroendocrine tumor of the medulla of the adrenal glands (originating in the chromaffin cells), or extra-adrenal chromaffin tissue that failed to involute after birth and secretes high amounts of catecholamines, mostly norepinephrine, plus epinephrine to a lesser extent.
• Patients in pheo crisis have had a massive release of adrenaline that causes major health problems including stroke, heart attack, heart failure, multiple organ failure, coma, and even death. These patients often require admission to an intensive care unit
• Extra-adrenal paragangliomas (often described as extra-adrenal pheochromocytomas) are closely related, though less common, tumors that originate in the ganglia of the sympathetic nervous system and are named based upon the primary anatomical site of origin
• In adults, approximately 80% of pheochromocytomas are unilateral and solitary, 10% are bilateral, and 10% are extra-adrenal. In children, a quarter of tumors are bilateral, and an additional quarter are extra-adrenal. Solitary lesions inexplicably favor the right side. Although pheochromocytomas may grow to large size (>3 kg), most weigh <100 g and are <10 cm in diameter. Pheochromocytomas are highly vascular.
• The diagnosis can be established by measuring catecholamines and metanephrines in plasma (blood) or through a 24-hour urine collection. Care should be taken to rule out other causes of adrenergic (adrenalin-like) excess
• Up to 25% of pheochromocytomas may be familial. Mutations of the genes VHL, RET, NF1(Gene 17 Neurofibromatosis type 1), SDHB and SDHD are all known to cause familial pheochromocytoma/extra-adrenal paraganglioma.
• MSCT dual- phase scanning has been considered adrenal chromaffin cell tumor diagnosis gold standard , the first deputy of the adrenal gland and spleen organ close by MSCT dual-phase scanning , intestine, diaphragm feet and vascular hypertrophy distinguish avoid mistaken adrenal tumor , followed by MSCT can also post processing techniques , the establishment of a three-dimensional image , further lesion localization ; when scanning area adrenal tumors and found no clinical suspicion of pheochromocytoma should be expanded scanning range , scanning the area below the diaphragm to the bladder , if still no abnormalities were found , the need for further scans of the chest , posterior mediastinum and skull base , but over the blind scan range is determined to iodine standard
• pheochromocytoma. For patients with an adrenal incidentaloma, if the metanephrine levels are between 1 and 2 times the upper limit of normal, there is a 30% chance of having a pheochromocytoma. It is important to note that certain medications can interfere with these tests, including some antidepressants and other medications for psychiatric diseases and high blood pressure. In addition, alcohol withdrawal, sleep apnea, and major stress like an operation or significant illness can interfere with test resmptoms of pheochromocytoma include: high blood pressure, rapid heart rate (palpitations), headache, flushing, and sweating. In addition, patients may feel like they are having an anxiety or panic attack (difficulty breathing, weakness, a feeling that something "bad" is happening). Other less common symptoms may include pale skin, blurred vision, weight loss, constipation, abdominal pain, high blood sugar levels, low blood pressure, and psychiatric disturbances. If these symptoms happen during a medical procedure, operation, after eating certain foods, or taking certain medicines like monoamine oxidase (MAO) inhibitors, the patient should be tested for pheochromocytoma right away. However, it is important to note that 40% of patients will present without any clear cut symptoms, but rather an adrenal tumor that was found on an imaging test done for another reason or at autopsy. (See Adrenal Incidentaloma
• The tumors are made up of large, polyhedral, pleomorphic chromaffin cells. Fewer than 10% of these tumors are malignant. As with several other endocrine tumors, malignancy cannot be determined from the histologic appearance; tumors that contain large number of aneuploid or tetraploid cells, as determined by flow cytometry, are more likely to recur. Local invasion of surrounding tissues or distant metastases indicate malignancy.