An abnormal shadow superimposed on the aorta was pointed out on the chest X-ray of an asymptomatic. His blood pressure and serological examinations were within normal range on admission to our hospital.
Urine VMA and catecholamine reactions were positive. As the result of CT scan, aortography, serological and urine examinations, an intrathoracic pheochromocytoma was suspected before surgery.
At thoracotomy a brownish, 4×3cm mass was recognized at the paravertebral area, related to the 5th intercostal nerve.
A hypertensive attack was evoked during decollement of the tumor.
Histological examination of the surgical specimen showed that it was a pheochromocytoma, and neurogenic secretory granules were found on electron microscopic examinations of the specimen. Postoperatively, urine VMA and catecholamine reduced to a normal range, and the patient is still asymptomatic, with a normal blood pressure.
