Role of proliferative marker index and KBTBD4 mutation in the pathological diagnosis of pineal parenchymal tumors

This study included 19 cases of PPTs [3 pineocytomas (PCs), 10 PPTs of intermediate differentiation (PPTID), and 6 pineoblastomas (PBs)]. Immunohistochemistry for Ki-67, PHH3, and DICER1, as well as Sanger sequencing analysis forKBTBD4 mutations, was performed using formalin-fixed paraffin-embedded tissue specimens that were resected during surgery. Tumor cell proliferation was quantified using an image analysis software. For the PHH3 and MIB-1 indices, a significant difference was observed between the PPTIDs and PBs (P <  0.05). Loss of DICER1 was not specific for PB; 0/3 PCs (0.0%), 2/9 PPTIDs (22.2%), and 2/4 PBs (50.0%).KBTBD4 mutations were detected in 1/3 PCs (33.3%), 6/9 PPTIDs (66.7%), and 0/4 PBs (0.0%). Thus, combined application of the proliferative marker index andKBTBD4 mutation analysis may be useful for the differential diagnosis of PPTs. Furthermore, detection ofKBTBD4 mutations using Sanger sequencing analysis may support the diagnosis of PPTID.
Source: Brain Tumor Pathology - Category: Neurology Source Type: research