Calcifying aponeurotic fibroma in a dog

Area of Science:

• Veterinary Neurology
• Comparative Pathology
• Neoplasia in Animals

Background:

• Calcifying aponeurotic fibromas are rare, benign tumors typically affecting the extremities of young animals.
• Involvement of the skull base and central nervous system is exceptionally uncommon.

Purpose of the Study:

• To report a unique case of a calcifying aponeurotic fibroma impacting the canine brainstem and cerebellum.
• To describe the clinical presentation, diagnostic findings, and outcome.

Main Methods:

• A 9-year-old mixed-breed female dog presented with progressive neurological deficits.
• Diagnostic imaging (computed tomography and magnetic resonance imaging) was performed.
• Histopathological examination confirmed the diagnosis.

Main Results:

• A large calcifying aponeurotic fibroma was identified in the occipital region, causing compression of the cerebellum and brainstem.
• Clinical signs included left head tilt, ataxia, anisocoria, horizontal nystagmus, and depressed consciousness.
• Tumor debulking and palliative care were attempted.

Conclusions:

• Calcifying aponeurotic fibromas, though rare, can occur in atypical locations and cause significant neurological compromise in dogs.
• Early recognition of progressive neurological signs is crucial for diagnosis and management.
• This case highlights the importance of considering unusual differentials for brainstem and cerebellar lesions.