A novel intravertebral tumor model in rabbits

Area of Science:

• Oncology
• Orthopedic Surgery
• Radiology

Background:

• Human epidural spinal metastases predominantly originate in the vertebral body.
• Existing animal models often lack intraosseous tumor placement, limiting their translational relevance.
• A robust animal model is crucial for studying spinal epidural tumor development and treatment.

Purpose of the Study:

• To establish and characterize a novel intraosseous intravertebral tumor model in rabbits.
• To investigate the onset of paraparesis, radiographic changes, and histopathological findings.
• To provide a more accurate preclinical model for human spinal epidural metastases.

Main Methods:

• VX2 carcinoma cells were injected into the vertebral bodies of New Zealand white rabbits.
• Lower extremity motor function was assessed daily to monitor for paraparesis.
• Magnetic resonance imaging (MRI) and computed tomographic (CT) scans were used to visualize tumor growth and spinal cord compression.
• Histopathological examination confirmed tumor characteristics and osteolytic activity.

Main Results:

• No gross tumor was detected on initial CT and MRI scans before paraparesis onset.
• At paraparesis onset, CT revealed osteolytic tumors, and MRI showed epidural tumors compressing the spinal cord.
• Histopathology confirmed carcinoma originating from the vertebral body with extensive osteolytic activity.
• Paraparesis developed in 89% of rabbits by the experiment's termination.

Conclusions:

• A novel intraosseous intravertebral tumor model in rabbits was successfully established.
• The model accurately mimics the onset of paraparesis, imaging features, and histopathological findings of human spinal epidural tumors.
• This model offers a valuable tool for future research into spinal metastases originating from the vertebral body.