All pineal tumors expressing germ cell tumor markers are not necessarily germ cell tumors: histopathological and molecular study of a midline primary intracranial sarcoma DICER1-mutant.

Fiche publication

Date publication

octobre 2022

Journal

Virchows Archiv : an international journal of pathology

Auteurs

Membres identifiés du Cancéropôle Est :
Pr CHENARD Marie-Pierre , Pr ENTZ-WERLE Natacha , Dr PENCREACH Erwan , Dr REITA Damien

Tous les auteurs :
Wolf T, Coca AH, Weingertner N, Chenard MP, Meurgey A, Reita D, Pencreach E, Varlet P, Entz-Werlé N, Lhermitte B

Lien Pubmed

https://www.ncbi.nlm.nih.gov/pubmed/36307659

Résumé

Primary intracranial sarcoma DICER1-mutant is a rare and newly recognized tumor type introduced in the 2021 WHO Classification of Central Nervous System Tumors. It is defined as a spindle cell sarcoma dysplaying eosinophilic intracytoplasmic globules, myogenic differentiation, and DICER1 gene mutation, either somatic or germline. Most reported cases were hemispheric except one, recently described in the pineal region. Here, we report the case of a 12 year-old boy with a pineally located tumor. Despite midline location, poorly differenciated morphology and germ cell marker expression, the association of DICER1 and NF1 hotspot mutations and a specific DNA methylation signature finally lead to the diagnosis of primary intracranial sarcoma DICER1-mutant instead of germ cell tumor. Furthermore, our molecular exploratory results involved a pathway, which was not previously evidenced in those DICER1 mutated cerebral sarcoma that is the canonical Wnt signaling driving likely a part of oncogenesis in this newly described pineal entity.