Digger

1. Digger 5 year old male neutered domestic ferret Case #: N07-648 Presenter: Travis Heskett, DVM Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

2. History • Presented to referring veterinarian for depression and hind limb weakness • Referring veterinarian had initially been concerned about insulinoma • Bloodwork WNL • Mass palpated at the base of the skull • Radiographs showed large osteoproliferative cervical vertebral lesion Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

3. CT Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

4. Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

5. Additional diagnostics • Aspirate cytology • Malignant cells of epithelial origin • Neurology consult • Grave prognosis • Euthanasia 1000x Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

6. Gross Findings--Dorsal Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

7. Gross Findings--Ventral Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

8. Histology • Infiltration of the neoplasm into musculature overlying skull and into the skull Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

9. Histology • Neoplasm infiltrating vertebral column with isolated neoplastic nodules within spinal canal Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

10. Histology • Production of new cartilage and bone by the neoplasm and invasion and remodeling of existing bone Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

11. Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

12. Immunohistochemistry Cytokeratin Vimentin Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

13. CNS Compression • Myelencephalon with moderate to marked axonal degeneration Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

14. Compression of the spinal cord with moderate axonal degeneration CNS Compression Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

15. Final Anatomic Diagnosis • Chordoma—caudodorsal skull in occipital and atlanto-occipital region with invasion into the calavarium, C1&C2, resulting in: • Compression of cerebellum, brainstem, and cervical spinal cord with moderate to marked axonal degeneration and minimal neuronal degeneration Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

16. Ferret Chordomas • 3-6 years of age • Typically occur at the tip of the tail beyond the last vertebral segment • Do not appear attached to preexisting bone • Slow growing, do not metastasize Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

17. AFIP website Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

18. Microscopic Appearance • Classic appearance is that of physaliferous cells surrounding cartilage with a central core of bone • Immunoreactive to both cytokeratin and vimentin • The origin of the bone and cartilage is controversial, but may arise from notocord differentiation within the neoplasm AFIP website Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

19. Chordomas • Arise from the remnants of the fetal notocord • Anywhere along the axial skeleton • Chordomas have also been reported in cervical and thoracic vertebrae of ferrets Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

20. Chordomas in other species • Also been reported in rats, mink, dogs, cats, and humans • In humans, they comprise approximately 1-4% of malignant osseous tumors. • In humans, 50% are present in the sacrococcygeal region, 25% in the sphenooccipital region, with the remainder arising in the vertebral axis. • Slow growing and locally invasive • 30% metastasize Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only

21. Special thanks to: Dr. Lisa Farina, pathologist Dr. David Taylor, advisor Histology service at UF CVM Fellow residents Questions??? Presented at SEVPAC 2008 – Permission granted for use on SEVPAC website only