Spinal chordoma

The patient presented with a history of back pain, responsive to NSAID, radiating to both lower extremities, of one and a half months' duration. There was pain at rest and on movement, paraparesis and instability on walking.

The patient presented with a history of back pain, responsive to NSAID, radiating to both lower extremities, of one and a half months' duration. There was pain at rest and on movement, paraparesis and instability on walking.

Physical examination showed muscle weakness of the lower extremities and numbness. The deep joint reflexes were normal, as was sensation.

Plain radiographs were obtained. On A/P view of the thoracolumbar spine a lucent area of right part of the body of the T12 vertebra was seen, with destruction of the lower end plate and the right pedicle. A lateral view of the thoracolumbar spine also demonstrated the lucent area of the posterior part of the T12 vertebra.

CT scanning demonstrated osteolysis of the right half of the T12 vertebra body and pedicle and development of a soft tissue mass extending into the spinal canal and a right paravertebral mass.

On MRI osteolysis of the right half of the T12 vertebra body and pedicle was again seen, as well as development of a soft tissue mass, extending into spinal canal and compressing the spinal cord, and a right paravertebral mass. There was an area of low signal intensity on T1-weighted images and a high signal area on T2-weighted images. T1-weighted images after administration of gadolinium demonstrated inhomogeneous enhancement (high signal).

Scintigraphy revealed increased uptake of radionuclear substance.

CT-guided FNAB of the paravertebral soft tissue was performed and cytological examination revealed abundant myxoid background surrounding clusters of physaliphorous cells (MGG X).

Chordoma is a destructive bone tumour believed to arise from notochord cell rests, which are normally precursors of vertebrae and intervertebral dics. The usual clinical presentation is in males between the ages of 40 and 70 years. It is locally malignant with a strong tendency to recur after attempted excision. Metastatic spread is unusual. The lesions are slow growing and become apparent due to pressure symptoms, with or without localised pain. Approximately half of the lesions arise in the sacrum and/or coccyx, the others in the basioccipital and basisphenoid regions of the skull. A vertebral origin is found in only 15% of patients. Adjacent vertebrae may be involved.

The lesion is lytic, relatively well defined, and usually oval or slightly lobulated with a sclerotic rim. It may contain areas of calcification. Disc space is frequently affected and there is often a soft tissue component that may have a calcified matrix.

In some cases, sclerosis predominates, leading to an "ivory" vertabrae appearance. On MRI, on T1-weighted images 75% of lesions are isointense and 25% are hypointense to adjacent vertebrae. On T2-weighted images the lesions have high intensity signal often with low-signal septa (70%).

Cytological examination reveals abundant myxoid background surrounding clusters of physaliphorous cells (MGG X).

The advantages of FNAB over core biopsy are the following. Fine needle (21-23G) can only be used in lytic lesions where the cortical bone is destroyed or it is very thin. FNAB is a simple, safe, cost effective and an out patient procedure. As a method it is rapid. Using Quick Qiemsa stain results can be available in 20-30 min. Especialy, in spinal lesions with cord compression FNAB can rapidly resolve the diagnostic problem. Finaly, it is less traumatic without significant complications . Due to this, multiple and multidirectional aspirates are permited to ensure adequate material. Chordoma is an excellent candidate of diagnosis by FNAB since it is a destructive tumor and the cytological findings are very characteristic of the lesion. These findings combined with radiological and clinical data permit correct diagnosis in the hands of experienced cytopathologist. When the lesion is located in the sacrum, plasmocytoma and giant cell tumour should be considered in the differential diagnosis. When the lesion is located in the basioccipital region, chondrosarcoma should be considered. Because of the possibility of the presence of chordoma in vertebral bodies, we suggest that it should be included in the differential diagnosis of osteolytic lesions of this area.