Fig. 2 | Modern Pathology

Fig. 2

From: Duplications of KIAA1549 and BRAF screening by Droplet Digital PCR from formalin-fixed paraffin-embedded DNA is an accurate alternative for KIAA1549-BRAF fusion detection in pilocytic astrocytomas

Fig. 2

Example of three cases difficult to classify. Case 1: a T2 weighted magnetic resonance imaging (MRI) showing a well limited tumor located in the cerebellum. b Hematoxylin and eosin (HE) stained section demonstrating a proliferation of elongated bipolar glial cells associated with numerous Rosenthal fibers (HE, ×40). c Presence of numerous axons revealed by anti-neurofilament immunostaining (×20). In this case, KIAA1549-BRAF fusion was recorded and final diagnosis was pilocytic astrocytoma. Case 2: d Temporal cystic lesion with a mural nodule enhanced after gadolinium injection on MRI. e Proliferation of elongated cells associated with Rosenthal fibers and eosinophilic granular bodies and perivascular lymphocytic infiltrate (HE, ×40). f Neurofilament immunostaining reveals absence of neuronal component (×20). This case exhibit neither KIAA1549-BRAF fusion nor BRAFV600E mutation and final diagnosis remains elusive. Case 3: g T2 weighted MRI showing a well-circumscribed spinal tumor. h Proliferation of monomorphous bipolar cells within a myxoid background (HE, ×40). i High proliferation index evaluated by anti-Ki67 antibody (×40). KIAA1549-BRAF fusion was recorded and final diagnosis was pilocytic astrocytoma

Back to article page