Classification des tumeurs de la région pinéale et leur traitement

Tumours are rare in the pineal region; they may affect children and adults and correspond to numerous and various entities. The localisation diagnosis using modern imaging techniques is easy. However, identifying the tumour type is more difficult; the diagnosis depends on a well-defined anatomopathological appraisal within each entity. Three histological groups have been identified: 25 to 30% are pineal parenchyma tumours (PPT) (pineocytoma, pineoblastoma and PPT with intermediate differentiation according to the WHO), an entity for which a new classification has been proposed, consisting of four histological grades; 25% are glial tumours among which are the recently individualised papillary tumours (PTPR); 30% are germ cell tumours (dysgerminomas and other germ cell tumours with or without secretion). Treatments vary, depending on the concerned entity. The treatment of germ cell tumours is based on chemotherapy and irradiation of the ventricular system, with an average recovery rate of 90%. In mixed germ cell tumours, with or without secretion, treatment combines chemotherapy (carboplatine, VP16 and Ifosfamide), eventual surgery of residuals, and focalised irradiation. Treatment for the other entities consists, above all, of surgery, which enable to obtain a significant fragment of the tumour and its complete excision in many cases. This treatment may result in recovery in benign types as cystic and pineocytoma. For malignant PPT, this treatment must be completed with irradiation and a more cautious prognosis, as well as chemotherapy for pineoblastoma cases. Long-term observation is necessary in all cases, for the neuro-cognitive follow-up and for the detection of early (germinal tumours) or late recurrence (PPT).