A Case Series Characterizing Pilomyxoid Astrocytomas in Childhood
Amy Rosenfeld1, Michael Etzl, David Lee
1*Center for Cancer and Blood Disorders †Institute for Molecular Medicine Departments of ‡Neuro-Radiology §Pathology ∥Barrow's Neurologic Institute, Phoenix Children's Hospital, Phoenix, AZ.
Background:
The term pilomyxoid astrocytoma (PMA) was added to the World Health Organization Classification of Tumours of the central nervous system in 2007. Pilomyxoid tumors are grade II tumors, considered to be variants of pilocytic astrocytomas. We attempted to determine if positron emission tomography (PET), proliferative index (PI), and BRAF V600E mutation help better define PMAs.
Observations:
We report 5 patients' clinical and neuroimaging findings, pathology (PI), and outcome. Four of the 5 patients had PET scans. Three patients showed [18F]fluoro-deoxyglucose hypermetabolism. The PI was elevated in all 5 cases and the BRAF V600E mutation was found in 3 of the 3 patients tested.
Conclusion:
Our data suggest that PMAs are hypermetabolic on PET, have elevated PIs and BRAF V600E mutations, and behave aggressively.
