Malignant peripheral nerve sheath tumor in a hamster.

Area of Science:

• Veterinary Pathology
• Oncology
• Rodent Medicine

Background:

• Peripheral nerve sheath tumors (PNSTs) are uncommon neoplasms affecting peripheral nerves.
• While documented in various species like dogs, PNSTs have not been previously reported in hamsters (Mesocricetus auratus).
• Understanding tumor behavior in diverse species aids comparative oncology and veterinary diagnostics.

Observation:

• An adult female golden hamster presented with a progressive subcutaneous mass on its forelimb.
• The mass led to significant limb enlargement, ulceration, drainage, and axillary lymph node metastasis.
• Cytology revealed pleomorphic neoplastic mesenchymal cells, and histology confirmed an invasive spindle cell neoplasm merging with a nerve.

Findings:

• Immunohistochemical staining was positive for vimentin, S100, and neuron-specific enolase.
• These markers, along with histologic morphology, are consistent with a malignant peripheral nerve sheath tumor.
• Metastasis to the lymph nodes was histologically confirmed.

Implications:

• This case represents the first report of a malignant peripheral nerve sheath tumor in golden hamsters.
• This finding expands the known oncological conditions affecting hamsters.
• It underscores the importance of considering PNSTs in the differential diagnosis of masses in hamsters and may inform future research into rodent neoplasms.