Pathological examination of spinal lesions in meningeal carcinomatosis.

For elucidation of the mechanism of spinal cord disorders associated with meningeal carcinomatosis, we investigated meningeal infiltration and parenchymal, vascular, and radicular damage in spinal cords subjected to pathological autopsy. Spinal cords were collected from 24 patients with a histopathological diagnosis of meningeal carcinomatosis. Infiltration from the subarachnoid space into the spinal cord occurred primarily along the perivascular tissue, and infiltration from the anterior median fissure to the anterior horn was found along the central artery in cases of marked meningeal dissemination. Meningeal dissemination was particularly evident with small cell carcinoma of lung, breast cancer and melanoma, and direct infiltration from the meninges into the spinal cord was found. Direct infiltration into the nerve roots was frequently observed, and infiltration was more evident in the dorsal roots than in the ventral roots, with loss of nerve fibers. Circular necrosis of the white matter in the periphery of the spinal cord was noted in cases of marked meningeal dissemination, which probably resulted from circulatory disturbance secondary to tumor infiltration. In cases of marked dorsal radiculopathy, there was secondary ascending degeneration of the posterior funiculus in cases of marked dorsal radiculopathy. These pathological changes associated with spinal cord disorders are important findings in reviewing spinal cord symptoms and radiographic findings in meningeal carcinomatosis.