Characterization of Molecular Genetic Alterations in GBMs Highlights a Distinctive Molecular Profile in Young AdultsJha, Prerana MSc*; Suri, Vaishali MD*; Singh, Geetika MD*; Jha, Pankaj MSc†; Purkait, Suvendu MD*; Pathak, Pankaj MSc*; Sharma, Vikas MSc*; Sharma, Mehar Chand MD*; Suri, Ashish MS, MCh‡; Gupta, Deepak MS, MCh‡; Mahapatra, Ashok Kumar MS, MCh‡; Sarkar, Chitra MD*Author Information Departments of *Pathology ‡Neurosurgery, All India Institute of Medical Sciences, New Delhi †Institute of Genomics and Integrative Biology, Delhi, India Funding disclosure: This study was funded by the Indian Council of Medical Research, New Delhi, India, and Neurosciences Center and Department of Pathology, All India Institute of Medical Sciences. Reprints: Chitra Sarkar, MD, Department of Pathology, All India Institute of Medical Sciences, New Delhi 110029, India (e-mail: [email protected]). Diagnostic Molecular Pathology: December 2011 - Volume 20 - Issue 4 - p 225–232 doi: 10.1097/PDM.0b013e31821c30bc Buy Metrics Abstract To evaluate age-related differences in histopathologic and molecular profile of glioblastomas (GBMs) at various age groups, with special reference to TP53 mutation, epidermal growth factor receptor (EGFR) amplification, EGFR vIII mutant, PTEN deletion, and IDH1 mutation. Agewise GBM incidence was calculated over a period of 5 years (2005 to 2009). Seventy-five GBMs were selected for molecular analysis. Majority of cases were in the age group of 41 to 60 years, and mean age was 43.6 years. Histology of all 75 cases selected for molecular profiling was identical. Primary adult GBMs showed EGFR amplification and PTEN deletion in majority (37.3% and 54.9%, respectively). TP53 and IDH1 mutations were rare (11.8% cases each). In secondary GBMs, TP53 (66.7%) and IDH1 mutations (44.4%) were most frequent. PTEN deletion was seen in 33.3% and none had EGFR amplification. Pediatric GBMs (<18 y) harbored frequent TP53 mutations (46.7%) and PTEN deletion in 40%. IDH1 mutations and EGFR amplification were absent. The molecular profile of primary GBMs in young adults (19 to 40 y) was distinctly different from that of adults older than 40 years. TP53 mutation was present in 20% cases. The frequency of EGFR amplification (13.3%) and PTEN deletion (33.3%) was significantly low (P=0.028 and 0.046, respectively). IDH1 mutation, which is rare in primary adult GBMs, was present in 40% of cases. Molecular heterogeneity exists within GBMs of different age cohorts. The molecular profile of GBMs in young adults is distinctly different. Thus, there is a strong need for further studies in various age groups to provide guidelines for therapeutic targeting. © 2011 Lippincott Williams & Wilkins, Inc.