PO-333 Molecular heterogenity in neuroblastoma (on behalf of turkish paediatric oncology group)

• Published in: ESMO open Vol. 3; no. Suppl 2; p. A358
• Main Authors: Aktas, T, Serinan, E, Ozdemir, P Ercetin, Aydin, M, Gokbayrak, O, Aylin, E, Aktas, S, Altun, Z, Olgun, N
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-07-2018
• ISSN: 2059-7029; 2059-7029
• DOI: 10.1136/esmoopen-2018-EACR25.845

IntroductionHeterogeneity in cancer is the difference of tumour cells in biological behaviours. Neuroblastoma treatment depends on risk classification including molecular tests. In this study, we searched for heterogeneity in DNA ploidy, MYCN amplification, 1pLOH, 11q deletion and 17q gain in metachronous neuroblastoma samples.Material and methods25 cases among 882 cases from Turkish Paediatric Oncology Group neuroblastoma database had multiple samples. MycN amplification, 1pLOH, 11qdel and 17q gain was evaluated by RT-PCR and DNA ploidy by flow cytometry for both fresh tumour samples. Statistical analyses are made using SPSS 22.0 by paired sample T test and frequencies were calculated.Results and discussionsThe mean age of 25 cases was 41.00±43.76 months. 13 patients were female and 12 patients were male. 25% of patients were in low risk, 25% intermediate risk and 50% in high risk group. Heterogeneity was observed in 20% cases for MycN, 44% for 1pLOH, 12% for 11qdel, 24% for 17q gain and 28% in DNA ploidy.ConclusionMolecular heterogeneity is observed in neuroblastoma among different tumour samples of the same patients. Molecular tests are better analysed in tumour tissues in each sample obtained at different times and cases should be evaluated for risk classification possible changes.