Identification and characterization of cytogenetic profile in olfactory neuroblastoma by array comparative genomic hybridization

Aim: the Olfactory Neuroblastoma (ONB) is an uncommon malignant tumor arising from the olfactory epithelium. Due to its rarity, the molecular and cytogenetic profiles are not well-known. The aim of the study is to better define the cytogenetic profile of ONB analyzed by Comparative Genomic Hybridization on Microarray (a-CGH) and identify possible correlations with clinical and pathological features.Materials and methods: 13 patients affected with ONB were collected and treated at Ospedale di Circolo of Varese, University of Insubria. At the Section of Biology and Medical Genetic, the DNA was extracted and isolated. We asseyed 14 samples using a-CGH technique: ten primary tumors, two relapsed tumors and two samples were from the same patient at onset and at relapse.Results: our results on chromosome imbalances highlight the highly heterogeneous presentation: seven of 13 samples showed multiple numerical changes and very few structural ones, while four samples showed an opposite pattern; one samples showed no imbalances. We did not reach firm evidence of any recurrent specific imbalances either at level of entire chromosomes or chromosome segments.Conclusion: Gain of chromosome 19 is the only corrispondence with literature data concerning an entire chromosome and most segmental gains and losses found in our cohort of patients are different from those indicated in the literature: the only similarities are the gain of 20q13 and the loss of segments of chromosome 15 and 22.