Endobronchial metastasis in a dog with sarcoma

Area of Science:

• Veterinary Pathology
• Comparative Oncology
• Canine Neoplasia

Background:

• Soft tissue sarcomas are common in dogs.
• Metastasis patterns can vary, but endobronchial involvement is rare.
• Understanding metastatic behavior is crucial for diagnosis and treatment.

Observation:

• A 3-year-old Australian Shepherd mix presented with a lumbar soft tissue sarcoma.
• The dog developed lung metastases characterized by neoplastic cells within bronchiolar walls.
• This led to airway obstruction and atelectasis, consistent with endobronchial metastasis.

Findings:

• Immunohistochemistry revealed neoplastic cells were vimentin-positive and negative for cytokeratin, CD18, synaptophysin, chromogranin, and desmin.
• This immunophenotype supports a mesenchymal origin for the tumor.
• The findings confirm a naturally occurring case of endobronchial metastasis in a canine patient.

Implications:

• This case expands the known spectrum of metastatic behavior for soft tissue sarcoma in dogs.
• It underscores the importance of considering unusual metastatic sites in cancer diagnosis.
• Further research into canine cancer metastasis may improve therapeutic strategies.