EMBR-09. EMBRYONAL TUMOR WITH MULTILAYERED ROSETTES: THE MD ANDERSON CANCER CENTER EXPERIENCE. Issue 2 (22nd June 2018) - Itzep, Nelda
Abstract: Embryonal Tumor with Multilayered Rosettes (ETMR) is a rare tumor of the central nervous system (CNS) with poor prognosis. To date no defined robust treatment strategy or advanced brain tumor imaging (ABTI) have been described for these malignancies. We performed a retrospective analysis and identified 8 pathology-proven ETMR cases from 2010–2017 treated at our institution, and evaluated our institutional experience, including imaging characteristics. Age ranged from 1.11 to 12.8 years. Tumors were located in the brainstem, spine, and frontal lobes. Presenting signs varied, and included cranial nerve and cerebellar dysfunction, cord compression and proptosis. Treatment included a combination of surgery, chemotherapy and radiation. The neuroimaging profile showed heterogeneous enhancement with minimal or no perilesional edema, and restricted diffusion. Magnetic resonance spectroscopy (MRS) demonstrated a choline/creatinine ratio greater than 2, depressed N-acetylaspartate (NAA), low myo-inositiol (in intermediate echo) and lipid/lactate peaks, typical for high-grade neoplasm. Diffusion tensor imaging (DTI) revealed deviated corticospinal tracts, with no evidence for tumor infiltration. Next generation sequencing assay failed to identify druggable mutations. Improved methods for early diagnosis of ETMR are evolving, most notably LIN28A immunostaining and 19q13.42 amplification detection. Though pre-operative MRI scans have been performed, advanced brain tumor imaging (ABTI), including MRS and DTI, have not been routinely reported in the ETMR literature. Prospective studies of these biologically elusive rare tumors should include, in addition to molecular characterization, neuroimaging with ABTI, which could aid diagnosis, surgical planning and follow-up of treatment response.