The 5-year survival rate was 40%(6/15),the 3-year survival rate was 57.1%(12/21),5 cases were treated before 1986.the main post operative treament was radiotherapy,the mean survival period was 28.5 months (8-64 months).

• 三年生存率57.；1%25（12/21）。 21例中1986年前治疗5例，术后辅以放射治疗为主，生存时间8月－64月，平均28