title: Heterozygosity status of 1p and 19q and its correlation with p53 protein expression and EGFR amplification in patients with astrocytic tumors: novel series from India.
abstract: There are few reports of loss of heterozygosity (LOH) of 1p and 19q in astrocytic tumors, especially glioblastoma multiforme (GBM). We evaluated 1p and 19q (either or both) heterozygosity status in 71 astrocytomas, including 6 pediatric cases: 20 diffuse astrocytomas (DA), 9 anaplastic astrocytomas (AA), and 42 GBM. In the GBMs, p53 protein expression was assessed by immunohistochemistry and epidermal growth factor receptor (EGFR) gene amplification by fluorescence in situ hybridization; TP53 sequencing was done in 15 of the GBMs. In adults, LOH of 1p or 19q was detected in 16% of DAs and 50% of GBMs; none of the AAs showed this alteration. In GBMs, LOH of 19q was most common (26%), followed by combined 1p and 19q LOH (13%) and 1p LOH (10%). Pediatric GBMs also harbored isolated 1p and 19q LOH (50%). Notably, LOH of 1p or 19q LOH was more frequent in p53 immunopositive secondary GBMs (61%) than in primary GBMs (17%). This suggests that LOH of 1p and 19q may be acquired during progression to secondary GBMs. Thus, 1p and 19q LOH can occur in astrocytic tumors, most commonly in secondary GBMs without morphological correlation with an oligodendroglial histology. The clinical significance of recognition of this subset of GBMs is based on several recent reports of association with better prognosis, although long-term follow-up studies are required.
authors.affiliation: Department of Pathology, All India Institute of Medical Sciences (AIIMS), New Delhi 110029, India.
authors.forename: Prerana
authors.initials: P
authors.lastname: Jha
authors.forename: Shipra
authors.initials: S
authors.lastname: Agarwal
authors.forename: Pankaj
authors.initials: P
authors.lastname: Pathak
authors.forename: Arti
authors.initials: A
authors.lastname: Srivastava
authors.forename: Vaishali
authors.initials: V
authors.lastname: Suri
authors.forename: Mehar Chand
authors.initials: MC
authors.lastname: Sharma
authors.forename: Kunzang
authors.initials: K
authors.lastname: Chosdol
authors.forename: Tapasya
authors.initials: T
authors.lastname: Srivastava
authors.forename: Deepak
authors.initials: D
authors.lastname: Gupta
authors.forename: Aditya
authors.initials: A
authors.lastname: Gupta
authors.forename: Ashish
authors.initials: A
authors.lastname: Suri
authors.forename: Chitra
authors.initials: C
authors.lastname: Sarkar
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001254:Astrocytoma / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D001932:Brain Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D002878:Chromosomes, Human, Pair 1; D002888:Chromosomes, Human, Pair 19; D005260:Female; D005784:Gene Amplification / Q000502:physiology; D018773:Genes, erbB-1; D006579:Heterozygote; D006801:Humans; D007194:India; D019656:Loss of Heterozygosity; D008297:Male; D008875:Middle Aged; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D055815:Young Adult
chemical_list: D016159:Tumor Suppressor Protein p53