Marielis Guzmán-Sánchez, DVM, MPH; Crystal Wee, BVMS; Mark Troxel, DVM, DACVIM; Jennifer O. Brisson, DVM, DACVR; Taryn A. Donovan, DVM, DACVP
Background
A 7-year-old female spayed Weimaraner mix presented with progressive back pain and paraparesis, initially managed medically without improvement. The patient developed neurological deficits, including ataxia and incontinence. Given the progression and signalment, the case raised suspicion for spinal neoplasia, a rare but significant cause of myelopathy in older, large-breed dogs. Chondrosarcoma, while uncommon in vertebrae, was included in the differential diagnosis based on clinical and imaging features.
Methods
The patient underwent neurologic examination, hematologic and biochemical testing, thoracic radiographs, and magnetic resonance imaging (MRI) of the spinal column (T3–S3). MRI sequences included pre- and post-contrast T1, T2, FLAIR, GRE, STIR, and fat-saturated views. Cerebrospinal fluid (CSF) analysis and necropsy with histopathology of T3–T8 were performed post-euthanasia.
Results
MRI revealed a large extradural, T2-hyperintense, contrast-enhancing mass at the T6 vertebra causing spinal cord compression. The lesion extended into the right epaxial muscles and was suspected to be neoplastic. CSF analysis showed mild albuminocytologic dissociation. Necropsy and histopathology confirmed a multinodular, infiltrative chondrosarcoma, causing bone destruction, gliosis, and myodegeneration. Radiographs failed to detect the lesion, but MRI clearly delineated its characteristics.
Limitations
Advanced diagnostics such as CT-guided biopsy and abdominal ultrasound were declined by the owner. Necropsy was limited to the vertebral column. The case lacked long-term follow-up and treatment outcome data due to early euthanasia, limiting assessment of therapeutic efficacy or survival.
Conclusions
This case highlights the diagnostic value of MRI in detecting vertebral chondrosarcoma, especially when radiographs are non-revealing. Although rare, vertebral chondrosarcoma should be a differential in middle-aged to older large-breed dogs with progressive myelopathy. Prompt cross-sectional imaging is critical for early diagnosis and potential therapeutic planning. Given its locally invasive nature and limited surgical options due to location, vertebral chondrosarcoma carries a guarded prognosis.
Magnetic resonance imaging sequences of the thoracic region in a 7-year-old spayed female Weimaraner mix with pelvic paraparesis and proprioceptive ataxia. In sagittal views, the head is to the left of the image. In transverse views, the right side of the patient is on the left side of the image. Sagittal (A) and transverse (B) T2 images; dorsal STIR (C), sagittal (D), and transverse (E) postcontrast T1-weighted images with fat saturation; and transverse gradient echo (F) images. A T2-hyperintense, STIR-hyperintense, rim contrast-enhancing mass is present at T6, extending laterally in a dorsocranial direction from the spinal canal toward the right hypaxial muscles. In the transverse gradient echo image (F), the lesion displays susceptibility artifact and was associated with hemorrhage and decreased cartilaginous matrix on histopathology. In the dorsal STIR image (C), the mass is severely compressing the right aspect of the spinal cord and disrupting the hypointense signal of the T5 right rib. Mild atrophy and contrast enhancement is present within the right hypaxial muscles.
How did we do?
Disclaimer: The summary generated in this email was created by an AI large language model. Therefore errors may occur. Reading the article is the best way to understand the scholarly work. The figure presented here remains the property of the publisher or author and subject to the applicable copyright agreement. It is reproduced here as an educational work. If you have any questions or concerns about the work presented here, reply to this email.
