Skip to main content
. Author manuscript; available in PMC: 2015 Jun 23.
Published in final edited form as: Am J Clin Pathol. 2013 Mar;139(3):275–288. doi: 10.1309/AJCPFO8IIDNBIJ8Y

Image 4.

Image 4

Cases 5 (A, C, E) and 6 (B, D, F). A World Health Organization (WHO) grade III anaplastic oligoastrocytoma of the right frontotemporal lobe (A) was immunonegative for R132H IDH1 (C), even though it showed an R132H IDH1 mutation on sequencing (E). In another case, a 36-year-old man had a right temporal WHO grade III anaplastic astrocytoma (B) that, aside from false-positive staining in red blood cells (D, arrow), was negative for R132H IDH1 on immunohistochemistry. Sequencing revealed an uncommon R132S IDH1 mutation (F).