title: The importance of 10q status in an outcomes-based comparison between 1p/19q fluorescence in situ hybridization and polymerase chain reaction-based microsatellite loss of heterozygosity analysis of oligodendrogliomas.
abstract: 1p/19q codeletion is a favorable prognostic marker of oligodendrogliomas. Although fluorescence in situ hybridization (FISH) and microsatellite-based polymerase chain reaction (PCR) for loss of heterozygosity (LOH) are common methods to test for 1p/19q codeletion, it is unclear which test is better at prognostic stratification. This study analyzed outcomes of 111 oligodendrogliomas with both 1p/19q FISH and LOH done at the time of diagnosis. Overall concordance between the 2 assays was 81.1%. In grade III oligodendrogliomas, LOH was better than FISH at survival stratification (p < 0.0001 for LOH vs p = 0.02 for FISH), although increasing the stringency of FISH interpretation criteria improved concordance and prognostic power. Oligodendrogliomas that were 1p/19q-codeleted by FISH but also had 10q LOH were negative for 1p/19q codeletion by PCR analysis in more than 70% of cases, with very poor survival in the grade III subset. Thus, although PCR-based LOH is a better stratifier of 1p/19q status, FISH still has clinical and prognostic utility, especially if 10q data can be incorporated.
authors.affiliation: Department of Pathology, University of Kentucky, Lexington, Kentucky, USA. craig.horbinski@uky.edu
authors.forename: Craig
authors.initials: C
authors.lastname: Horbinski
authors.forename: Marina N
authors.initials: MN
authors.lastname: Nikiforova
authors.forename: Jonathan
authors.initials: J
authors.lastname: Hobbs
authors.forename: Stephanie
authors.initials: S
authors.lastname: Bortoluzzi
authors.forename: Kathleen
authors.initials: K
authors.lastname: Cieply
authors.forename: Sanja
authors.initials: S
authors.lastname: Dacic
authors.forename: Ronald L
authors.initials: RL
authors.lastname: Hamilton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D002879:Chromosomes, Human, Pair 10 / Q000235:genetics*; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D019656:Loss of Heterozygosity / Q000235:genetics*; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics*; D008875:Middle Aged; D009837:Oligodendroglioma / Q000235:genetics* / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000379:methods; D011446:Prospective Studies