대한대장항문학회

Malignant degeneration of mature cystic teratoma has been reported in 1∼3% of cases, usually between the age of 30 and 70 years with a peak incidence of 40∼60 years. The most common malignancy developing in such tumors is squamous cell carcinoma<br>arising in a mature cystic teratoma. Hirakawa reported two patients with benign teratomas diagnosed 25 and 32 years prior to surgery for malignancy and Dorothea reported a patient who was diagnosed as benign teratoma 50 years prior to operate for<br>carcinoma. But there has been no report of squamous cell carcinoma arising in the mature cystic teratoma with direct invasion to gastrointestinal tract. We report a case of squamous cell carcinoma with direct invasion to transverse colon and jejunum in<br>62-year-old female who was diagnosed as mature cystic teratoma 20 years ago.<br>