The researchers examined 71diffuse intrinsic pontine tumors:
- 65 were high grade gliomas, 8 were low grade and 3 were PNETs.
- survival was not related to grade.
- leptomeningeal spread was present in one third of cases.
- 68% had K27M-H3.
- these tumors were histologically heterogenous, however increased homogeneity was found of the histone mutation.
- the histone mutations were also present in low grade tumors that had worse outcomes.
The authors conclude with a call for "incorporation of histological and molecular data"- specifically stating "histone mutational status at biopsy"- in designing new therapies for DIPG.
There has been a rash of publication regarding K27M mutations recently. Several of the other abstracts for this meeting feature this histone mutation in DIPG. I am sure more will be coming in the future.
Genetic and histopathological spectrum of paediatric diffuse intrinsic pontine gliomas
Inhibition of PRC2 Activity by a Gain-of-Function H3 Mutation Found in Pediatric Glioblastoma