Cytokeratin expression by sarcomas does not indicate synovial origin in dogs

Area of Science:

• Veterinary Pathology
• Canine Oncology
• Immunohistochemistry

Background:

• Sarcomas are common tumors in dogs, with varying origins and prognoses.
• Cytokeratin expression is sometimes used to infer epithelial or synovial origin in tumors.
• The diagnostic utility of cytokeratin in canine sarcomas requires further investigation.

Purpose of the Study:

• To evaluate the diagnostic value of cytokeratin immunohistochemistry in canine sarcomas.
• To determine if cytokeratin expression correlates with sarcoma location (subcutaneous vs. articular).
• To assess the impact of cytokeratin expression and sarcoma location on overall survival in dogs.

Main Methods:

• Cytokeratin immunohistochemistry was performed on 33 canine sarcoma samples (25 subcutaneous, 8 articular).
• Neoplastic cell expression of cytokeratin was quantified.
• Kaplan-Meier survival analysis was used to compare survival rates based on cytokeratin status and tumor location.

Main Results:

• Cytokeratin expression was observed in 32% of subcutaneous sarcomas and 14% of articular sarcomas.
• No significant difference in overall survival was found between dogs with subcutaneous and articular sarcomas.
• Overall survival did not differ significantly between cytokeratin-positive and cytokeratin-negative sarcomas.

Conclusions:

• Cytokeratin expression does not reliably indicate synovial origin in canine sarcomas.
• Neither sarcoma location nor cytokeratin expression significantly affects overall survival in this study.
• Cytokeratin immunohistochemistry is not a helpful diagnostic tool for determining sarcoma origin in dogs.