endodermal sinus tumor

n.

A malignant neoplasm occurring in the gonads, in sacrococcygeal teratomas, and in the mediastinum and producing alpha-fetoprotein.yolk-sac tumor

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.