7/10/2007 Case 3: Parenchymal neurocytoma. Metanaplastic glioneurocytoma


Clinical History:

This 42 year old woman had vomiting with dehydration, followed by one or two partial seizures with a numb hand and loss of consciousness, which resulted in
performance of an MRI scan showing a non-enhancing left temporal lobe mass. She also reported having difficulty with numbers, a major problem as she is an
accountant. This was gross totally resected in June 2006 (slide 1). She did well until recently when she had new onset of back pain, weakness in both legs, and then more sudden onset of a thoracic sensory level. An MRI scan showed several enhancing nodules in the spinal subarachnoid space, one probably also in the thoracic spinal cord. There were also suspicious enhancing nodules in the cerebral leptomeninges, and there was a recurrent non-enhancing mass in the residual temporal lobe. The thoracic spinal cord mass was biopsied (slide 2).

Diagnostic Notes:

This mass was diagnosed as a “meningioma” in Manhattan.  This mass was called “Fibro-osseous lesion consistent with cementifying variant of ossifying fibroma” by Dr. May Parisien of Columbia.  This entity has also been called “aggressive psammomatoid ossifying fibroma” and “cementifying fibroma.”  This is a locally invasive often (30-58%) recurrent lesion that does not metastasize and for which total excision is the treatment of choice.  It arises in the nasal sinuses and orbit (70%) and also in the palate and anterior fossa.  It may show intracranial extension.  It is most common in teenagers (15 years old) but has been reported from 5-54 years of life.  The male/female ratio is 1.3/1.  It is EMA negative but CK may be positive.  Vimentin is positive.  Reticulin occurs around woven bone.  If you polarize the lesion you well see woven and lamellar bone.  The question may be asked, do reports of “Sino nasal psammomatous meningioma” really refer to this entity?

Slide Image:

view high resolution slide image