前縦隔に発生したpigmented paraganglioma

Pigmented Paraganglioma in the Anterior Mediastinum

傍神経節腫（paraganglioma）は副腎髄質以外の自律神経系の神経節より発生する褐色細胞腫であり，縦隔に発生することはまれである1，2）．そのうち病理学的に細胞質内にメラニンの沈着を伴うものがpigmented paragangliomaとされる3）．

Pigmented paraganglioma of the anterior mediastinum is extremely rare. We report a 72-year-old female patient who was pointed out an anterior mediastinum tumor showed by chest computed tomography（CT） scan during a medical check up. The tumor was 50×35 mm showing gradual enlargement and was slightly homogenously contrasted by CT scan and magnetic resonance imaging（MRI）. During the resection of the tumor, sudden elevations of both blood pressure up to 205 mmHg and tachycardia up to 131 beat per minate（bpm）was noted on tumor manipulation. Pathologically, the tumor was diagnosed as pigmented paraganglioma with adjacent lymph node metastasis and microscopic extracapsular invasion. The patient is well 5 years post-surgery without recurrence.