Incidence of pineal tumours. A review of the literature.

The knowledge of the incidence of pineal tumours is important not only for diagnostic care but also for its therapeutic programme. We reviewed the incidence of pineal tumours reported in literature in an attempt to establish if a difference existed between pineal gland tumours and the pineal region tumours as different authors use both expressions to indicate the same thing. The rate of frequency of these tumours is useful to guide the therapeutic choice for patients as the decisional tree is completely different for either germ cell tumours, pineal gland tumours or pineal gliomas and eventually papillary tumours of the pineal region. According to the French Register of pineal tumours, true pineal tumours represent: 27% pineal parenchymal tumours (PPT), 27% germ cell tumours, 17% gliomas, 8% papillary tumours. True pineal gland tumours are represented by: pineocytomas - (13%), pineal parenchymal tumours with intermediary differentiation PTT-ID - (66%) and pinealoblastomas - (21%). There was no statistical difference found between the French register and the Lyon series concerning histological diagnosis. It seemed to us important to discover its true incidence by comparing the data published in the literature and to stress the utility of the French Register for these uncommon tumours not only for recording new histological cases but also to document clinical symptomatology, therapeutic programmes, length of follow-up and clinical results for each patient treated. A better understanding of their natural history and improved evaluation of different treatments and their complications should contribute to improve clinical results.