History of Management of Supratentorial Central Neurocytomas in Children

Understanding of Disease

• 1982 – Hassoun first used term: The term central neurocytoma was first used by Hassoun et al. (1) to describe a neuronal tumor in young adults located in the lateral ventricle and histologically similar to an oligodendroglioma. These tumors were previously referred to as ependymomas of the foramen of Munro or as intraventricular oligodendrogliomas. Over the past 20 years, various tumors mimicking central neurocytomas but located outside the supratentorial ventricular system have been described.
• 2000s – atypical form described: The term “central neurocytoma” should be restricted to neoplasms in the lateral and third ventricles, and the term “extraventricular central neurocytoma” should be used for all other tumors. An aggressive form of this tumor has been described as “atypical neurocytoma.”

Technological Development

• Immunohistochemistry and subtyping: These tumors have been classified as low-grade lesions with low cell proliferation indices; recurrent genetic changes in chromosomes 2p, 10q, and 18q in central neurocytomas have been described (2), and chromosomal regions for additional mapping and cloning of candidate genes that are important in the development of central neurocytomas have been identified. A separate group of similar tumors with high mitotic figures (greater than 3 per high power field), focal necrosis, less marked neuronal differentiation on synaptophysin immunoreactivity, and a MIB-1 labeling index greater than 5.2 have been identified as the so-called “atypical neurocytomas” (3, 4).
• Development of adjuvant therapies: Tumors that are atypical or incompletely resected require adjuvant therapy. Chemotherapy (5) and stereotactic radiotherapy (6) have been proposed as salvage techniques in residual and recurrent groups of these tumors.

Surgical Technique

• Standard techniques: The standard surgical techniques for gross total resection of brain tumors are used, as, clearly, that is the procedure of choice for these tumors.
• Image guidance: The exact pathway of access with minimal passage through eloquent areas is possible with the use of neuronavigation (7). Intraoperative MRI, which makes possible the monitoring of the totality of the resection, has been referred to in various communications.
• Endoscopic removal: Neuroendoscopic methods of tumor removal have been described (8).