Papillary tumors of the pineal region

The papillary tumor of the pineal region, also briefly PTPR, is a rare brain tumor, probably originating from specialized ependymal cells of Subcommissuralorgans. Papillary tumors of the pineal region are located on the back wall of the third ventricle and are in close spatial relationship to the pineal gland ( Pineal gland ). After the first description in 2003, over 119 cases have been published. In the very great majority of children and young adults are affected. A connection with a hereditary disease is not known.

Clinical manifestations

Due to its location typical papillary tumors of the pineal region often impede the flow of cerebrospinal fluid, which can lead to an increase in intracranial pressure. Headache, nausea and vomiting are nonspecific symptoms. Due to pressure of the tumor on the quadrigeminal plate is not rare disorders of ocular motor with two pictures on ( Parinaud's syndrome). In magnetic resonance imaging to face papillary tumors of the pineal region dar. as kontrastmittelanreichernde masses

Pathology

Histologically, there is a neuroectodermal tumor with a papillary structure has an epithelium - like appearance. The tumor cells often sit with broad projections on the blood vessels, so that the impression clumsy pseudo- rosettes formed. Also ependymal rosettes as in ependymomas may occur. The mitotic activity of the tumor cells is generally moderate. Necrosis are common and can lead them to misdiagnosis of a Plexuskarzinoms. In the past, papillary tumors of the pineal region have often been misinterpreted as a choroid plexus papilloma or papillary ependymoma. The immunohistochemical expression profile ( strong often punctate expression of cytokeratin ), usually with a lack of expression of epithelial membrane antigen ( EMA, in ependymomas positive) and the potassium channel Kir7.1 (positive in plexus papillomas and Plexuskarzinomen ) allows, in most cases, a diagnosis between.

Pathogenesis

About one involved in the pathogenesis of papillary tumors of the pineal mechanisms there is still no evidence.

Therapy

Usually complete surgical removal is desired. If this is not possible, irradiation may be considered. As in the treatment of ependymomas adjuvant chemotherapy plays a somewhat minor role. Treatment should preferably be carried out in clinical trials, which are currently (2012 ) but still are still in the planning stage.

Forecast

Even after complete surgical removal of the prognosis of papillary tumors of the pineal region is characterized by frequent relapses. The biological value of papillary tumors of the pineal region of grade II-III of the WHO classification of tumors of the central nervous system must therefore be estimated analogously.