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[Development of spinal bone metastasis by MBT-2 tumor in mice].

The biology of skeletal metastasis is poorly understood. In order to establish an animal model of spinal bone metastasis, we injected MBT-2 tumor cells into the tail vein of C3H/He mice while the inferior vena cava was occluded. By this technique, the tumor cells were transferred into the vertebral plexus. Spinal lesions developed in 12 of 15 (80%) experimental mice and in none of the control mice. All bone lesions resulted in local bone destruction. The predominant site of bone metastasis was lumbarvertebrae; other affected sites were thrpelvis and coccyges. This model should be of value in understanding the pathogenesis of spinal bone metastasis and in studying the effects of various agents on the prevention and control of spinal lesions.