Embryonal tumors with multilayered rosettes (ETMR) are rare small round blue cell tumor of the central nervous system and are one of the most aggressive brain tumors usually encountered in children.
Previously embryonal tumors with multilayered rosettes (ETMR) were known as embryonal tumor with abundant neuropil and true rosettes (ETANTR). This term has, however, been removed from the 2016 update to WHO classification of CNS tumors in favour of embryonal tumors with multilayered rosettes (ETMR) which incorporates not only ETANTR but also ependymoblastoma and CNS PNET which have also been removed from the classification) 6. This has resulted due to the presence of amplification of the C19MC region on chromosome 19 in both CNS PNET and ETANTR, suggesting that these are the one entity with variable growth pattern 6.
ETMR occurs in children aged 4 and under, mostly in children under 2, and is more common in girls, unlike the other CNS embryonal tumors, in which boys are equally or more commonly affected.
Treatment and Prognosis
Current treatment options for ETMR include surgical resection, systemic chemotherapy and craniospinal radiation (when appropriate).
Unfortunately, the prognosis is dismal, with most recent articles reporting ~75% of cases have died within the median survival of 9 months