Chordomas in Fischer 344 Rats

Abstract

Tissue sections and records of 56 rats with chordoma, identified in the National Toxicology Program's (NTP) data base of approximately 115,000 rats, were examined to determine morphological characteristics, incidence, and aspects of biological behavior. Chordomas occurred in aged rats, originated predominantly in lumbosacral vertebrae, were highly malignant, occurred three times more often in male versus female rats, and commonly produced bilateral posterior paresis, paralysis, and/or distention of the colon and rectum. © 1988, American College of Veterinary Pathologists. All rights reserved.