PATHOANATOMICAL AND RADIOGRAPHIC FINDINGS IN SPINAL BREAST-CANCER METASTASES

Spine specimens infested with breast cancer metastases, ranging from l ocalized seed of small tumor deposits to massive invasion and vertebra l collapse, were frozen in situ, removed, examined with both conventio nal radiography and high resolution computed tomography (CT), and then studied in great detail by serial cryoplaning. The majority of metast ases in the total of 53.5 vertebrae were lytic, and most were in close contact with the vertebral wall or the endplates. Depressions and def ects of the endplates were associated with compensatory expansion of t he intervertebral discs. Although lytic lesions abutting endplate defe cts had the radiological appearance of metastases, all contained herni ated disc material rather than tumor. Only four of the 29 grossly dest royed and collapsed vertebrae showed extrusion of the posterior verteb ral wall into the spinal canal. Tumor growth in the epidural space was rare. There were no macroscopical reactive changes of the osseoligame ntous or neurovascular spinal elements to the metastases, but abnormal ities of the posterior elements (kissing spines, facet joint subluxati on, and pars interarticularis failure) were common.