Characteristics of spinal cord compression in adenocarcinoma of prostate.

Of 611 patients with biopsy-proved adenocarcinoma of the prostate, spinal cord compression developed in 41 (6.7%) at a median interval of twenty-four months after primary diagnosis. Spinal cord involvement most often occurred in the thoracic area, with 95 per cent of patients showing radiographic evidence of osseous vertebral metastasis at the level of cord compression. All lesions but one were located extradurally, and patients with Stage D2 disease, by virtue of bony metastases, were therefore at greatest risk for development of neurologically compressive disease. There was also a significant increase in the incidence of spinal cord involvement among the more poorly differentiated tumors, although tumor histology did not appear to influence the median interval between vertebral metastasis and cord compromise. Survival following spinal cord involvement was relatively poor and unrelated to tumor differentiation. Forty-six per cent of patients survived less than six months and 20 per cent less than two months. The two most noteworthy survivors are alive at thirty and ninety-seven months, the latter after combined treatment for an intradural lesion.