Department of Forensic Medicine, National Institute of Scientific Investigation, Seoul, Korea. ykmoo@freechal.com Department of Forensic Medicine, Catholic University Medical School, Seoul, Korea.

A 65 year-old female was suddenly expired soon after arriving in emergency room. Before arriving, she complained chest discomfort. Her neck mass was diagnosed as thyroid tumor about 11 years ago. She was recommended operation, but not taken due to arrhythmia. The neck mass was originally diagnosed as thyroid mass (goiter) by radiologic studies. The mass (10.5 x 9.5 x 7.0 cm, 319 gm) is mainly located in the lower neck and partly in the anterior superior mediastinum. The trachea is compressed by the mass and its tubal structure is flattened. The cause of death is mechanical asphyxia by thymoma (type B1 according to the WHO classification of thymoma, and stage I according to Masaoka's classification). On review of her past history, paraneoplastic syndrome including myasthenia gravis is not present. Generally, the patient with large thymic mass shows symptoms including chest pain, respiratory difficulty, hemoptysis, cough, superior vena cava syndrome. Although the symptoms related with its mass effect are common, but the death from mechanical asphyxia by thymoma is very rare in recent days.

Key Words : thymoma, asphyxia