Case of the Month

Section Editor: Nicholas Stence, MD
Children's Hospital Colorado, Aurora, CO

August 2018

Next case coming September 4...

Embryonal Tumor with Multilayered Rosettes (ETMR)

Background
- ETMR (2016 WHO classification) was formerly known as ETANTR (embryonal tumor with abundant neuropil and true rosettes), and before that known as ependymoblastoma and some medulloepitheliomas;
- Any childhood CNS tumor with alterations at 19q13.42 (C19MC amplification) is now classified as ETMR, regardless of histology;
- LIN28a IHC can also be used;
- Almost always children < 3-4 years;
- Usually short duration of symptoms;
- Distinctly aggressive behavior (median survival of 0.8 years).
Imaging
- Few case reports of imaging findings, further complicated by terminology changes over the years;
- More often supratentorial than infratentorial;
- When supratentorial, they are usually:
  - Large
  - Well-circumscribed
  - Poorly enhancing solid component with peripheral cysts
  - Uniform restricted diffusion
  - Even fewer MRS case reports, some describe elevated choline and taurine.
Therapy
- Complete resection, if possible;
- No standard regimen due to rarity, although craniospinal radiation, high dose chemotherapy with stem cell rescue has been used.