A 53-year-old obese man was transferred to the hospital with new onset seizures and a left frontal intracranial tumor diagnosed by a CT scan. The preceding medical history was significant for chronic obstructive pulmonary disease, asbestos exposure, 30-pack-years of tobacco use and chronic alcoholism.
On admission he was found to have possible sepsis, respiratory failure and severe hypoxemia, and was placed on a mechanical ventilator. Urine cultures identified a urinary tract infection due to Escherichia coli. Electrocardiogram revealed inferior myocardial infarction and chest x-ray exhibited possible bronchopneumonic changes. MRI scans revealed a large cystic and necrotic left frontal mass, measuring 7.9 x 7 x 7cm in the transverse, anteroposterior and cephalocaudal planes (figure 1). There was heterogeneous enhancement. The tumor extended through the genu of the corpus callosum with moderate left to right frontal midline shift. His clinical status was stabilized and he was transferred to the transitional care unit for craniotomy and tumor resection.
An image-guided left frontal craniotomy revealed a firm subdural tumor on the left frontal cortical surface that was resected en-bloc, preserving the pial planes and stripping it from the falx cerebri.
GROSS SURGICAL NEUROPATHOLOGY:
The specimen consisted of multiple irregular fragments of white-tan rubbery tissue admixed with globules of bosselated, white-tan rubbery tissue, measuring 14 x 11 x 5 cm in aggregate (figure 2). Sections revealed central cystic degeneration surrounded by solid white tissue (figure 3). Also present was an irregular piece of tan mature bone that measured 3 x 2 x 1.5cm (figure 4). Sections of the bone revealed central cancellous bone surrounded by a rim of cortical bone.
Examination of H&E stained sections of tumor revealed mature hyaline cartilage showing a distinct perichondrium, a basophilic matrix and clusters of lacunae arranged in a lobular pattern (figure 5). Each lacuna was occupied by a single mature chondrocyte without nuclear atypia or binucleation (figure 6). As noted on gross examination, there was central cystic degeneration and coagulative necrosis of the cartilaginous matrix and chondrocytes. There was also focal mineralization of the matrix and endochondral ossification forming mature, compact and trabecular bone surrounded by cortical bone. The bone trabeculae exhibited irregular lamellae of bone with lacunae containing osteocytes, and is separated by a labyrinth of interconnecting spaces containing a cellular bone marrow, some fibrous and adipose tissue. The bone marrow exhibited unremarkable trilineage hematopoiesis (figure 7). The tumor was adherent to dura mater, but did not invade the brain parenchyma.