Histiocytic sarcoma with central nervous system involvement in dogs: 19 cases (2006-2012)

Area of Science:

• Veterinary Neurology
• Veterinary Oncology
• Comparative Pathology

Background:

• Reports of canine histiocytic sarcoma (HS) involving the central nervous system (CNS) are infrequent, primarily consisting of limited case studies.
• This scarcity necessitates further investigation into this rare condition.

Purpose of the Study:

• To document the signalment, clinical presentation, clinicopathologic data, and diagnostic imaging findings.
• To analyze treatment strategies and outcomes for dogs diagnosed with CNS HS.

Main Methods:

• A retrospective case series involving 19 dogs with histopathologically confirmed CNS HS.
• Review of medical records, diagnostic imaging (CNS), and histopathologic samples.

Main Results:

• Retrievers and Pembroke Welsh Corgis were disproportionately represented.
• Tumors affected the brain (14 dogs) or spinal cord (5 dogs); 15 cases were CNS-confined.
• Key findings included variable imaging, predominant extraaxial brain masses, profound meningeal enhancement, and pleocytosis in all evaluated CSF samples, with a median survival of 3 days.

Conclusions:

• Canine CNS HS exhibits unique breed predispositions compared to HS in other organs.
• Distinctive imaging features (e.g., brain herniation, meningeal enhancement) and clinicopathologic findings (pleocytosis) may aid in differentiating CNS HS from other central nervous system neoplasms.