February 2003: a 53-year-old male with new onset seizures

• Published in: Brain pathology (Zurich, Switzerland) Switzerland), 2003-07, Vol.13 (3), p.419-420
• Main Authors: Omalu, Bennet I, Wiley, Clayton A, Hamilton, Ronald L
• Format: Article
• Language: English
• Subjects: Bone Neoplasms - complications; Bone Neoplasms - pathology; Bone Neoplasms - surgery; Corpus Callosum - pathology; Humans; Magnetic Resonance Imaging; Male; Mesenchymoma - complications; Mesenchymoma - pathology; Mesenchymoma - surgery; Middle Aged; Myocardial Infarction - physiopathology; Osteochondroma - complications; Osteochondroma - pathology; Osteochondroma - surgery; Seizures - etiology; Seizures - pathology; Tomography, X-Ray Computed
• ISSN: 1015-6305; 1750-3639
• DOI: 10.1111/j.1750-3639.2003.tb00046.x

The February COM. A 53-year-old obese man presented with new onset seizures and an MRI scan revealed a large cystic and necrotic heterogeneously enhancing left frontal mass. Craniotomy revealed a firm subdural tumor on the cortical surface that was delivered en-bloc preserving the pial planes and stripping it from the falx cerebri. The tumor consisted of multiple irregular fragments of white-tan rubbery tissue admixed with globules of bosselated, white-tan rubbery tissue and a fragment of bone. Sections of the tumor revealed mature hyaline cartilage with no atypia of the chondrocytes. There was focal mineralization and endochondral ossification. A diagnosis of intracranial mesenchymal osteochondroma was made. Osteochondroma, a benign cartilaginous neoplasm comprised of mature hyaline cartilage with focal ossification, is the most common benign bone tumor. Extraskeletal (mesenchymal) osteochondromas are known to originate from non-skeletal or non-cartilaginous tissue. Intracranial osteochondromas are uncommon, typically arising from the base of the skull. Only about 15% of intracranial osteochondromas arise supratentorially, from the dura, usually in a parafalcine frontoparietal location and some have been a component of Maffucci's syndrome and Ollier disease. Intracranial osteochondromas can occur at any age with a predilection for younger individuals. Intracranial mesenchymal osteochondromas exhibit a benign clinical course. Typically, the histomorphology resembles mature hyaline cartilage without anaplastic proliferation of chondrocytes or nuclear atypia, with a lobular arrangement of clusters of lacunae containing single chondrocytes. Transition to osteochondrosarcoma has rarely been documented.