Pineal Tumors in Childhood. Epidemiology, Pathophysiology, and Surgical Approaches

For the purposes of surgical indications and considerations, we prefer that the general, anatomical term 'pineal tumors' be used for all tumors in the region of the pineal gland, and that such developmental, histological, or congenital terms as dysgerminoma, pinealoma, and teratoma be reserved exclusively for neuropathological descriptive purposes. Of our 26 children - age range from 7 months to 16 years - treated for pineal tumors during the 9-year period 1972-1980 inclusive, all presented with hydrocephalus necessitating ventriculoperitoneal shunts. This incidence of pineal tumors represents 9.4% of the total number of brain tumors in childhood (275) which were managed by the senior author during this period of time. 23 of the 26 children were operated for direct attack of the tumor, with the postoperative mortality being 1 (as defined by death preceding discharge from hospital): a 7-month-old child with a medulloepithelioma which rapidly, within 3 weeks, invaded the thalamus, corpus callosum, brain stem, and cerebellum, causing death. It is recommended that cerebral spinal fluid (CSF) be taken from the ventricular system at the time of insertion of the ventriculoperitoneal shunt and that this fluid be analyzed for alpha-fetoprotein (AFP), human chorionic gonadotrophins (HCG), and carcinoembryonic antigen (CEA), and that cytology be performed to search for neoplastic cells. If the marker studies are positive, or malignant neoplastic cells identified at cytology, then it is recommended that Röentgen therapy be given to the patient and that no direct surgical attack of the tumor be attempted. On the other hand, if the marker studies and cytology are negative, direct surgical attack is recommended after the ventriculoperitoneal shunt, when all signs of an increase in intracranial pressure disappear. None of our patients had steroid management for the increase in intracranial pressure. The shunt sufficed. We suggest that the surgical approach (parasagittal, occipital-transtentorial, suboccipital-supracerebellar) be planned on the basis of the direction of displacement of the Galenic (internal cerebral vein, and great vein of Galen) and supraculminate (pre-central and superior cerebellar) venous systems; (1) when the Galenic system is displaced inferiorly, a parasagittal approach is recommended; (2) when the Galenic system is displaced superiorly, a suboccipital supracerebellar approach is recommended; (3) when the supraculminate system is displaced posteriorly, an occipital transtentorial approach is recommended.