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Clinical and pathological characteristics of primary intraspinal hemangiopericytoma and choice of treatment.

BACKGROUND
Primary intraspinal hemangiopericytoma is a rare malignant mesenchymal tumor with high rates of recurrence and metastasis. Surgery is the main therapeutic procedure for this lesion. This clinical research was undertaken to analyze the pathological characteristics, clinical course, and the choice of treatment for this lesion.


METHODS
Twenty-three patients with primary intraspinal hemangiopericytomas were treated from 1987 to 2004. The clinical and imaging features, pathological findings, therapeutic procedures, and prognosis were analyzed retrospectively.


RESULTS
Primary intraspinal hemangiopericytoma is more likely to attack middle-aged persons. The tumor mainly manifests as muscle weakness and sensor abnormalities. Microscopic examination showed slit-like vascular spaces and oral- or spindle-shaped cells with slightly acidic cytoplasm and oral nuclei. Tumors were subtotally resected in 11 patients, subtotally resected with postoperative radiotherapy in 4, totally resected in 5, and totally resected with postoperative radiotherapy in 3. Two patients were given spinal stabilization after total resection. Recurrence and metastatic rates were 50% and 0 in intradural patients. They were 73% and 27% in extradural patients, respectively.


CONCLUSIONS
The tumor should be resected en bloc with the neighboring dural mater to reduce recurrence and metastasis. Patients with subtotal resection need adjuvant radiotherapy. Patients with evident spinal involvement may benefit from spinal stabilization. The prognosis of the lesion arising from the dural mater is better.